mirror of
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* Fix generate_code script path * [Python] Make StartVector public Make StartVector vector public since it is already being used in generated code * [Python] Improve vector creation for Python API Makes Python API for vectors cleaner like Rust and Swift --------- Co-authored-by: Derek Bailey <derekbailey@google.com>
2997 lines
81 KiB
Markdown
2997 lines
81 KiB
Markdown
# Tutorial
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This tutorial provides an example of how to work with FlatBuffers in a variety
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of languages. The following topics will cover all the steps of using FlatBuffers
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in your application.
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1. Writing a FlatBuffers schema file (`.fbs`).
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2. Using the `flatc` compiler to transform the schema into language-specific
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code.
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3. Importing the generated code and libraries into your application.
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4. Serializing data into a flatbuffer.
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5. Deserializing a flatbuffer.
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The tutorial is structured to be language agnostic, with language specifics in
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code blocks providing more context. Additionally, this tries to cover the major
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parts and type system of flatbuffers to give a general overview. It's not
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expected to be an exhaustive list of all features, or provide the best way to do
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things.
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## FlatBuffers Schema (`.fbs`)
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To start working with FlatBuffers, you first need to create a
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[schema](schema.md) file which defines the format of the data structures you
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wish to serialize. The schema is processed by the `flatc` compiler to generate
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language-specific code that you use in your projects.
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The following
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[`monster.fbs`](https://github.com/google/flatbuffers/blob/master/samples/monster.fbs)
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schema will be used for this tutorial. This is part of the FlatBuffers
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[sample code](https://github.com/google/flatbuffers/tree/master/samples) to give
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complete sample binaries demonstrations.
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FlatBuffers schema is a Interface Definition Language (IDL) that has a couple
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data structures, see the [schema](schema.md) documentation for a detail
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description. Use the inline code annotations to get a brief synopsis of each
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part of the schema.
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```proto title="monster.fbs" linenums="1"
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// Example IDL file for our monster's schema.
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namespace MyGame.Sample; //(1)!
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enum Color:byte { Red = 0, Green, Blue = 2 } //(2)!
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// Optionally add more tables.
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union Equipment { Weapon } //(3)!
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struct Vec3 { //(4)!
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x:float; //(5)!
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y:float;
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z:float;
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}
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table Monster { //(6)!
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pos:Vec3; //(7)!
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mana:short = 150; //(8)!
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hp:short = 100;
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name:string; //(9)!
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friendly:bool = false (deprecated); //(10)!
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inventory:[ubyte]; //(11)!
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color:Color = Blue;
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weapons:[Weapon]; //(12)!
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equipped:Equipment; //(13)!
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path:[Vec3];
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}
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table Weapon {
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name:string;
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damage:short;
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}
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root_type Monster; //(14)!
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```
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1. FlatBuffers has support for namespaces to place the generated code into.
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There is mixed level of support for namespaces (some languages don't have
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namespaces), but for the C family of languages, it is fully supported.
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2. Enums definitions can be defined with the backing numerical type. Implicit
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numbering is supported, so that `Green` would have a value of 1.
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3. A union represents a single value from a set of possible values. Its
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effectively an enum (to represent the type actually store) and a value,
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combined into one. In this example, the union is not very useful, since it
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only has a single type.
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4. A struct is a collection of scalar fields with names. It is itself a scalar
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type, which uses less memory and has faster lookup. However, once a struct is
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defined, it cannot be changed. Use tables for data structures that can evolve
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over time.
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5. FlatBuffers has the standard set of scalar numerical types (`int8`, `int16`,
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`int32`, `int64`, `uint8`, `uint16`, `uint32`, `uint64`, `float`, `double`),
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as well as `bool`. Note, scalars are fixed width, `varints` are not
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supported.
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6. Tables are the main data structure for grouping data together. It can evolve
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by adding and deprecating fields over time, while preserving forward and
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backwards compatibility.
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7. A field that happens to be a `struct`. This means the data of the `Vec3`
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struct will be serialized inline in the table without any need for offset.
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8. Fields can be provided a default value. Default values can be configured to
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not be serialized at all while still providing the default value while
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deserializing. However, once set, a default value cannot be changed.
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9. A `string` field which points to a serialized string external to the table.
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10. A deprecated field that is no longer being used. This is used instead of
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removing the field outright.
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11. A `vector` field that points to a vector of bytes. Like `strings`, the
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vector data is serialized elsewhere and this field just stores an offset to
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the vector.
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12. Vector of `tables` and `structs` are also possible.
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13. A field to a `union` type.
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14. The root of the flatbuffer is always a `table`. This indicates the type of
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`table` the "entry" point of the flatbuffer will point to.
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## Compiling Schema to Code (`flatc`)
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After a schema file is written, you compile it to code in the languages you wish
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to work with. This compilation is done by the [FlatBuffers Compiler](flatc.md)
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(`flatc`) which is one of the binaries built in the repo.
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### Building `flatc`
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FlatBuffers uses [`cmake`](https://cmake.org/) to build projects files for your
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environment.
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=== "Unix"
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```sh
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cmake -G "Unix Makefiles"
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make flatc
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```
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=== "Windows"
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```sh
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cmake -G "Visual Studio 17 2022"
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msbuild.exe FlatBuffers.sln
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```
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See the documentation on [building](building.md) for more details and other
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environments. Some languages also include a prebuilt `flatc` via their package
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manager.
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### Compiling Schema
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To compile the schema, invoke `flatc` with the schema file and the language
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flags you wish to generate code for. This compilation will generate files that
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you include in your application code. These files provide convenient APIs for
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serializing and deserializing the flatbuffer binary data.
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=== "C++"
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```sh
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flatc --cpp monster.fbs
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```
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=== "C"
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!!! Note
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If you're working in C, you need to use the separate project
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[FlatCC](https://github.com/dvidelabs/flatcc) which contains a schema
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compiler and runtime library in C for C. See
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[flatcc build instructions](https://github.com/dvidelabs/flatcc#building).
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Please be aware of the difference between `flatc` and `flatcc` tools.
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```sh
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cd flatcc
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mkdir -p build/tmp/samples/monster
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bin/flatcc -a -o build/tmp/samples/monster samples/monster/monster.fbs
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# or just
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flatcc/samples/monster/build.sh
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```
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=== "C#"
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```sh
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flatc --csharp monster.fbs
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```
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=== "Dart"
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```sh
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flatc --dart monster.fbs
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```
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=== "Go"
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```sh
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flatc --go monster.fbs
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```
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=== "Java"
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```sh
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flatc --java monster.fbs
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```
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=== "JavaScript"
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```sh
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flatc --js monster.fbs
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```
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=== "Kotlin"
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```sh
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flatc --kotlin monster.fbs
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```
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=== "Lobster"
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```sh
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flatc --lobster monster.fbs
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```
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=== "Lua"
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```sh
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flatc --lua monster.fbs
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```
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=== "PHP"
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```sh
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flatc --php monster.fbs
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```
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=== "Python"
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```sh
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flatc --python monster.fbs
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```
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=== "Rust"
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```sh
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flatc --rust monster.fbs
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```
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=== "Swift"
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```sh
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flatc --swift monster.fbs
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```
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=== "TypeScript"
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```sh
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flatc --ts monster.fbs
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```
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You can deserialize flatbuffers in languages that differ from the language that
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serialized it. For purpose of this tutorial, we assume one language is used for
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both serializing and deserializing.
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## Application Integration
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The generated files are then included in your project to be built into your
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application. This is heavily dependent on your build system and language, but
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generally involves two things:
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1. Importing the generated code.
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2. Importing the "runtime" libraries.
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=== "C++"
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```c++
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#include "monster_generated.h" // This was generated by `flatc`
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#include "flatbuffers.h" // The runtime library for C++
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// Simplifies naming in the following examples.
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using namespace MyGame::Sample; // Specified in the schema.
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```
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=== "C"
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```c
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#include "monster_builder.h" // Generated by `flatcc`.
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// Convenient namespace macro to manage long namespace prefix.
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#undef ns
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// Specified in the schema.
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#define ns(x) FLATBUFFERS_WRAP_NAMESPACE(MyGame_Sample, x)
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// A helper to simplify creating vectors from C-arrays.
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#define c_vec_len(V) (sizeof(V)/sizeof((V)[0]))
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```
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=== "C#"
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```c#
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using Google.FlatBuffers; // The runtime library for C#
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using MyGame.Sample; // The generated files from `flatc`
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```
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=== "Dart"
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```dart
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import 'package:flat_buffers/flat_buffers.dart' as fb;
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// Generated by `flatc`.
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import 'monster_my_game.sample_generated.dart' as myGame;
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```
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=== "Go"
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```go
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import (
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flatbuffers "github.com/google/flatbuffers/go"
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sample "MyGame/Sample"
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)
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```
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=== "Java"
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```java
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import MyGame.Sample.*; //The `flatc` generated files. (Monster, Vec3, etc.)
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import com.google.flatbuffers.FlatBufferBuilder;
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```
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=== "JavaScript"
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```javascript
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// The following code is an example - use your desired module flavor by
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// transpiling from TS.
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var flatbuffers = require('/js/flatbuffers').flatbuffers;
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var MyGame = require('./monster_generated').MyGame; // Generated by `flatc`.
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//------------------------------------------------------------------------//
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// The following code is for browser-based HTML/JavaScript. Use the above
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// code for JavaScript module loaders (e.g. Node.js).
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<script src="../js/flatbuffers.js"></script>
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<script src="monster_generated.js"></script> // Generated by `flatc`.
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```
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=== "Kotlin"
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```kotlin
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import MyGame.Sample.* //The `flatc` generated files. (Monster, Vec3, etc.)
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import com.google.flatbuffers.FlatBufferBuilder
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```
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=== "Lobster"
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```lobster
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import from "../lobster/" // Where to find flatbuffers.lobster
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import monster_generated
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```
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=== "Lua"
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```lua
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-- require the flatbuffers module
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local flatbuffers = require("flatbuffers")
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-- require the generated files from `flatc`.
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local color = require("MyGame.Sample.Color")
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local equipment = require("MyGame.Sample.Equipment")
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local monster = require("MyGame.Sample.Monster")
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local vec3 = require("MyGame.Sample.Vec3")
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local weapon = require("MyGame.Sample.Weapon")
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```
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=== "PHP"
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```php
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// It is recommended that your use PSR autoload when using FlatBuffers in
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// PHP. Here is an example from `SampleBinary.php`:
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function __autoload($class_name) {
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// The last segment of the class name matches the file name.
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$class = substr($class_name, strrpos($class_name, "\\") + 1);
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// `flatbuffers` root.
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$root_dir = join(DIRECTORY_SEPARATOR, array(dirname(dirname(__FILE__))));
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// Contains the `*.php` files for the FlatBuffers library and the `flatc`
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// generated files.
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$paths = array(join(DIRECTORY_SEPARATOR, array($root_dir, "php")),
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join(DIRECTORY_SEPARATOR,
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array($root_dir, "samples", "MyGame", "Sample")));
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foreach ($paths as $path) {
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$file = join(DIRECTORY_SEPARATOR, array($path, $class . ".php"));
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if (file_exists($file)) {
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require($file);
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break;
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}
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}
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}
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```
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=== "Python"
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```py
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import flatbuffers
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# Generated by `flatc`.
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import MyGame.Sample.Color
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import MyGame.Sample.Equipment
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import MyGame.Sample.Monster
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import MyGame.Sample.Vec3
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import MyGame.Sample.Weapon
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```
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=== "Rust"
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```rust
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// import the flatbuffers runtime library
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extern crate flatbuffers;
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// import the generated code
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#[allow(dead_code, unused_imports)]
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#[path = "./monster_generated.rs"]
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mod monster_generated;
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pub use monster_generated::my_game::sample::{root_as_monster,
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Color, Equipment,
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Monster, MonsterArgs,
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Vec3,
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Weapon, WeaponArgs};
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```
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=== "Swift"
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```swift
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/**
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// make sure that monster_generated.swift is included in your project
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*/
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import Flatbuffers
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// typealiases for convenience
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typealias Monster = MyGame1_Sample_Monster
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typealias Weapon = MyGame1_Sample_Weapon
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typealias Color = MyGame1_Sample_Color
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typealias Vec3 = MyGame1_Sample_Vec3
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```
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=== "TypeScript"
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```ts
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// note: import flatbuffers with your desired import method
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import { MyGame } from './monster_generated';
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```
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For some languages the runtime libraries are just code files you compile into
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your application. While other languages provide packaged libraries via their
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package managers.
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The generated files include APIs for both serializing and deserializing
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FlatBuffers. So these steps are identical for both the consumer and producer.
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## Serialization
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Once all the files are included into your application, it's time to start
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serializing some data!
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With FlatBuffers, serialization can be a bit verbose, since each piece of data
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must be serialized separately and in a particular order (depth-first, pre-order
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traversal). The verbosity allows efficient serialization without heap
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allocations, at the cost of more complex serialization APIs.
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For example, any reference type (e.g. `table`, `vector`, `string`) must be
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serialized before it can be referred to by other structures. So its typical to
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serialize the data from leaf to root node, as will be shown below.
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### FlatBufferBuilder
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Most languages use a Builder object for managing the binary array that the data
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is serialized into. It provides an API for serializing data, as well as keeps
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track of some internal state. The generated code wraps methods on the Builder
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object to provide an API tailored to the schema.
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First instantiate a Builder (or reuse an existing one) and specify some memory
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for it. The builder will automatically resize the backing buffer when necessary.
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=== "C++"
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```c++
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// Construct a Builder with 1024 byte backing array.
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flatbuffers::FlatBufferBuilder builder(1024);
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```
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=== "C"
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```c
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flatcc_builder_t builder, *B;
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B = &builder;
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// Initialize the builder object.
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flatcc_builder_init(B);
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```
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=== "C#"
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```c#
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// Construct a Builder with 1024 byte backing array.
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FlatBufferBuilder builder = new FlatBufferBuilder(1024);
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```
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=== "Dart"
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```dart
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// Construct a Builder with 1024 byte backing array.
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var builder = new fb.Builder(initialSize: 1024);
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```
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=== "Go"
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```go
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// Construct a Builder with 1024 byte backing array.
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builder := flatbuffers.NewBuilder(1024)
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```
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=== "Java"
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```java
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// Construct a Builder with 1024 byte backing array.
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FlatBufferBuilder builder = new FlatBufferBuilder(1024);
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```
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=== "JavaScript"
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```javascript
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// Construct a Builder with 1024 byte backing array.
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var builder = new flatbuffers.Builder(1024);
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```
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=== "Kotlin"
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```kotlin
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// Construct a Builder with 1024 byte backing array.
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val builder = FlatBufferBuilder(1024)
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```
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=== "Lobster"
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```lobster
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// Construct a Builder with 1024 byte backing array.
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let builder = flatbuffers_builder {}
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```
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=== "Lua"
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```lua
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-- Construct a Builder with 1024 byte backing array.
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local builder = flatbuffers.Builder(1024)
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```
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=== "PHP"
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```php
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// Construct a Builder with 1024 byte backing array.
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$builder = new Google\FlatBuffers\FlatbufferBuilder(1024);
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```
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=== "Python"
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```py
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# Construct a Builder with 1024 byte backing array.
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builder = flatbuffers.Builder(1024)
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```
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=== "Rust"
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```rust
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// Construct a Builder with 1024 byte backing array.
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let mut builder = flatbuffers::FlatBufferBuilder::with_capacity(1024);
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```
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|
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=== "Swift"
|
|
|
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```swift
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// Construct a Builder with 1024 byte backing array.
|
|
let builder = FlatBufferBuilder(initialSize: 1024)
|
|
```
|
|
|
|
=== "TypeScript"
|
|
|
|
```ts
|
|
// Construct a Builder with 1024 byte backing array.
|
|
let builder = new flatbuffers.Builder(1024);
|
|
```
|
|
|
|
Once a Builder is available, data can be serialized to it via the Builder APIs
|
|
and the generated code.
|
|
|
|
### Serializing Data
|
|
|
|
In this tutorial, we are building `Monsters` and `Weapons` for a computer game.
|
|
A `Weapon` is represented by a flatbuffer `table` with some fields. One field is
|
|
the `name` field, which is type `string` and the other `damage` field is a
|
|
numerical scalar.
|
|
|
|
```c title="monster.fbs" linenums="28"
|
|
table Weapon {
|
|
name:string;
|
|
damage:short;
|
|
}
|
|
```
|
|
|
|
#### Strings
|
|
|
|
Since `string` is a reference type, we first need to serialize it before
|
|
assigning it to the `name` field of the `Weapon` table. This is done through the
|
|
Builder `CreateString` method.
|
|
|
|
Let's serialize two weapon strings.
|
|
|
|
=== "C++"
|
|
|
|
```c++
|
|
flatbuffers::Offset<String> weapon_one_name = builder.CreateString("Sword");
|
|
flatbuffers::Offset<String> weapon_two_name = builder.CreateString("Axe");
|
|
```
|
|
|
|
`flatbuffers::Offset<>` is a just a "typed" integer tied to a particular
|
|
type. It helps make the numerical offset more strongly typed.
|
|
|
|
=== "C"
|
|
|
|
```c
|
|
flatbuffers_string_ref_t weapon_one_name
|
|
= flatbuffers_string_create_str(B, "Sword");
|
|
flatbuffers_string_ref_t weapon_two_name
|
|
= flatbuffers_string_create_str(B, "Axe");
|
|
```
|
|
|
|
=== "C#"
|
|
|
|
```c#
|
|
Offset<String> weaponOneName = builder.CreateString("Sword");
|
|
Offset<String> weaponTwoName = builder.CreateString("Axe");
|
|
```
|
|
|
|
=== "Dart"
|
|
|
|
```dart
|
|
final int weaponOneName = builder.writeString("Sword");
|
|
final int weaponTwoName = builder.writeString("Axe");
|
|
```
|
|
|
|
=== "Go"
|
|
|
|
```go
|
|
weaponOne := builder.CreateString("Sword")
|
|
weaponTwo := builder.CreateString("Axe")
|
|
```
|
|
|
|
=== "Java"
|
|
|
|
```java
|
|
int weaponOneName = builder.createString("Sword")
|
|
int weaponTwoName = builder.createString("Axe");
|
|
```
|
|
|
|
=== "JavaScript"
|
|
|
|
```javascript
|
|
var weaponOne = builder.createString('Sword');
|
|
var weaponTwo = builder.createString('Axe');
|
|
```
|
|
|
|
=== "Kotlin"
|
|
|
|
```kotlin
|
|
val weaponOneName = builder.createString("Sword")
|
|
val weaponTwoName = builder.createString("Axe")
|
|
```
|
|
|
|
=== "Lobster"
|
|
|
|
```lobster
|
|
let weapon_one = builder.CreateString("Sword")
|
|
let weapon_two = builder.CreateString("Axe")
|
|
```
|
|
|
|
=== "Lua"
|
|
|
|
```lua
|
|
local weaponOne = builder:CreateString("Sword")
|
|
local weaponTwo = builder:CreateString("Axe")
|
|
```
|
|
|
|
=== "PHP"
|
|
|
|
```php
|
|
$weapon_one_name = $builder->createString("Sword")
|
|
$weapon_two_name = $builder->createString("Axe");
|
|
```
|
|
|
|
=== "Python"
|
|
|
|
```py
|
|
weapon_one = builder.CreateString('Sword')
|
|
weapon_two = builder.CreateString('Axe')
|
|
```
|
|
|
|
=== "Rust"
|
|
|
|
```rust
|
|
let weapon_one_name = builder.create_string("Sword");
|
|
let weapon_two_name = builder.create_string("Axe");
|
|
```
|
|
|
|
=== "Swift"
|
|
|
|
```swift
|
|
let weapon1Name = builder.create(string: "Sword")
|
|
let weapon2Name = builder.create(string: "Axe")
|
|
```
|
|
|
|
=== "TypeScript"
|
|
|
|
```ts
|
|
let weaponOne = builder.createString('Sword');
|
|
let weaponTwo = builder.createString('Axe');
|
|
```
|
|
|
|
|
|
This performs the actual serialization (the string data is copied into the
|
|
backing array) and returns an offset. Think of the offset as a handle to that
|
|
reference. It's just a "typed" numerical offset to where that data resides in
|
|
the buffer.
|
|
|
|
#### Tables
|
|
|
|
Now that we have some names serialized, we can serialize the `Weapon` tables.
|
|
Here we will use one of the generated helper functions that was emitted by
|
|
`flatc`. The `CreateWeapon` function takes in the Builder object, as well as the
|
|
offset to the weapon's name and a numerical value for the damage field.
|
|
|
|
=== "C++"
|
|
|
|
```c++
|
|
short weapon_one_damage = 3;
|
|
short weapon_two_damage = 5;
|
|
|
|
// Use the `CreateWeapon()` shortcut to create Weapons with all the fields
|
|
// set.
|
|
flatbuffers::Offset<Weapon> sword =
|
|
CreateWeapon(builder, weapon_one_name, weapon_one_damage);
|
|
flatbuffers::Offset<Weapon> axe =
|
|
CreateWeapon(builder, weapon_two_name, weapon_two_damage);
|
|
```
|
|
|
|
=== "C"
|
|
|
|
```c
|
|
uint16_t weapon_one_damage = 3;
|
|
uint16_t weapon_two_damage = 5;
|
|
|
|
ns(Weapon_ref_t) sword
|
|
= ns(Weapon_create(B, weapon_one_name, weapon_one_damage));
|
|
ns(Weapon_ref_t) axe
|
|
= ns(Weapon_create(B, weapon_two_name, weapon_two_damage));
|
|
```
|
|
|
|
=== "C#"
|
|
|
|
```c#
|
|
short weaponOneDamage = 3;
|
|
short weaponTwoDamage = 5;
|
|
|
|
// Use the `CreateWeapon()` helper function to create the weapons, since we
|
|
// set every field.
|
|
Offset<Weapon> sword =
|
|
Weapon.CreateWeapon(builder, weaponOneName, weaponOneDamage);
|
|
Offset<Weapon> axe =
|
|
Weapon.CreateWeapon(builder, weaponTwoName, weaponTwoDamage);
|
|
```
|
|
|
|
=== "Dart"
|
|
|
|
```dart
|
|
final int weaponOneDamage = 3;
|
|
final int weaponTwoDamage = 5;
|
|
|
|
final swordBuilder = new myGame.WeaponBuilder(builder)
|
|
..begin()
|
|
..addNameOffset(weaponOneName)
|
|
..addDamage(weaponOneDamage);
|
|
final int sword = swordBuilder.finish();
|
|
|
|
final axeBuilder = new myGame.WeaponBuilder(builder)
|
|
..begin()
|
|
..addNameOffset(weaponTwoName)
|
|
..addDamage(weaponTwoDamage);
|
|
final int axe = axeBuilder.finish();
|
|
```
|
|
|
|
Note, as an alternative, the previous steps can be combined using the
|
|
generative Builder classes.
|
|
|
|
```dart
|
|
final myGame.WeaponBuilder sword = new myGame.WeaponObjectBuilder(
|
|
name: "Sword",
|
|
damage: 3,
|
|
);
|
|
|
|
final myGame.WeaponBuilder axe = new myGame.WeaponObjectBuilder(
|
|
name: "Axe",
|
|
damage: 5,
|
|
);
|
|
```
|
|
|
|
=== "Go"
|
|
|
|
```go
|
|
// Create the first `Weapon` ("Sword").
|
|
sample.WeaponStart(builder)
|
|
sample.WeaponAddName(builder, weaponOne)
|
|
sample.WeaponAddDamage(builder, 3)
|
|
sword := sample.WeaponEnd(builder)
|
|
|
|
// Create the second `Weapon` ("Axe").
|
|
sample.WeaponStart(builder)
|
|
sample.WeaponAddName(builder, weaponTwo)
|
|
sample.WeaponAddDamage(builder, 5)
|
|
axe := sample.WeaponEnd(builder)
|
|
```
|
|
|
|
=== "Java"
|
|
|
|
```java
|
|
short weaponOneDamage = 3;
|
|
short weaponTwoDamage = 5;
|
|
|
|
// Use the `createWeapon()` helper function to create the weapons, since we
|
|
// set every field.
|
|
int sword = Weapon.createWeapon(builder, weaponOneName, weaponOneDamage);
|
|
int axe = Weapon.createWeapon(builder, weaponTwoName, weaponTwoDamage);
|
|
```
|
|
|
|
=== "JavaScript"
|
|
|
|
```javascript
|
|
// Create the first `Weapon` ('Sword').
|
|
MyGame.Sample.Weapon.startWeapon(builder);
|
|
MyGame.Sample.Weapon.addName(builder, weaponOne);
|
|
MyGame.Sample.Weapon.addDamage(builder, 3);
|
|
var sword = MyGame.Sample.Weapon.endWeapon(builder);
|
|
|
|
// Create the second `Weapon` ('Axe').
|
|
MyGame.Sample.Weapon.startWeapon(builder);
|
|
MyGame.Sample.Weapon.addName(builder, weaponTwo);
|
|
MyGame.Sample.Weapon.addDamage(builder, 5);
|
|
var axe = MyGame.Sample.Weapon.endWeapon(builder);
|
|
```
|
|
|
|
=== "Kotlin"
|
|
|
|
```kotlin
|
|
val weaponOneDamage: Short = 3;
|
|
val weaponTwoDamage: Short = 5;
|
|
|
|
// Use the `createWeapon()` helper function to create the weapons, since we
|
|
// set every field.
|
|
val sword = Weapon.createWeapon(builder, weaponOneName, weaponOneDamage)
|
|
val axe = Weapon.createWeapon(builder, weaponTwoName, weaponTwoDamage)
|
|
```
|
|
|
|
=== "Lobster"
|
|
|
|
```lobster
|
|
let sword = MyGame_Sample_WeaponBuilder { b }
|
|
.start()
|
|
.add_name(weapon_one)
|
|
.add_damage(3)
|
|
.end()
|
|
|
|
let axe = MyGame_Sample_WeaponBuilder { b }
|
|
.start()
|
|
.add_name(weapon_two)
|
|
.add_damage(5)
|
|
.end()
|
|
```
|
|
|
|
=== "Lua"
|
|
|
|
```lua
|
|
-- Create the first 'Weapon'
|
|
weapon.Start(builder)
|
|
weapon.AddName(builder, weaponOne)
|
|
weapon.AddDamage(builder, 3)
|
|
local sword = weapon.End(builder)
|
|
|
|
-- Create the second 'Weapon'
|
|
weapon.Start(builder)
|
|
weapon.AddName(builder, weaponTwo)
|
|
weapon.AddDamage(builder, 5)
|
|
local axe = weapon.End(builder)
|
|
```
|
|
|
|
=== "PHP"
|
|
|
|
```php
|
|
$sword = \MyGame\Sample\Weapon::CreateWeapon($builder, $weapon_one_name, 3);
|
|
$axe = \MyGame\Sample\Weapon::CreateWeapon($builder, $weapon_two_name, 5);
|
|
```
|
|
|
|
=== "Python"
|
|
|
|
```py
|
|
# Create the first `Weapon` ('Sword').
|
|
MyGame.Sample.Weapon.Start(builder)
|
|
MyGame.Sample.Weapon.AddName(builder, weapon_one)
|
|
MyGame.Sample.Weapon.AddDamage(builder, 3)
|
|
sword = MyGame.Sample.Weapon.End(builder)
|
|
|
|
# Create the second `Weapon` ('Axe').
|
|
MyGame.Sample.Weapon.Start(builder)
|
|
MyGame.Sample.Weapon.AddName(builder, weapon_two)
|
|
MyGame.Sample.Weapon.AddDamage(builder, 5)
|
|
axe = MyGame.Sample.Weapon.End(builder)
|
|
```
|
|
|
|
=== "Rust"
|
|
|
|
```rust
|
|
// Use the `Weapon::create` shortcut to create Weapons with named field
|
|
// arguments.
|
|
let sword = Weapon::create(&mut builder, &WeaponArgs{
|
|
name: Some(weapon_one_name),
|
|
damage: 3,
|
|
});
|
|
let axe = Weapon::create(&mut builder, &WeaponArgs{
|
|
name: Some(weapon_two_name),
|
|
damage: 5,
|
|
});
|
|
```
|
|
|
|
=== "Swift"
|
|
|
|
```swift
|
|
// start creating the weapon by calling startWeapon
|
|
let weapon1Start = Weapon.startWeapon(&builder)
|
|
Weapon.add(name: weapon1Name, &builder)
|
|
Weapon.add(damage: 3, &builder)
|
|
// end the object by passing the start point for the weapon 1
|
|
let sword = Weapon.endWeapon(&builder, start: weapon1Start)
|
|
|
|
let weapon2Start = Weapon.startWeapon(&builder)
|
|
Weapon.add(name: weapon2Name, &builder)
|
|
Weapon.add(damage: 5, &builder)
|
|
let axe = Weapon.endWeapon(&builder, start: weapon2Start)
|
|
```
|
|
|
|
=== "TypeScript"
|
|
|
|
```ts
|
|
// Create the first `Weapon` ('Sword').
|
|
MyGame.Sample.Weapon.startWeapon(builder);
|
|
MyGame.Sample.Weapon.addName(builder, weaponOne);
|
|
MyGame.Sample.Weapon.addDamage(builder, 3);
|
|
let sword = MyGame.Sample.Weapon.endWeapon(builder);
|
|
|
|
// Create the second `Weapon` ('Axe').
|
|
MyGame.Sample.Weapon.startWeapon(builder);
|
|
MyGame.Sample.Weapon.addName(builder, weaponTwo);
|
|
MyGame.Sample.Weapon.addDamage(builder, 5);
|
|
let axe = MyGame.Sample.Weapon.endWeapon(builder);
|
|
```
|
|
|
|
|
|
The generated functions from `flatc`, like `CreateWeapon`, are just composed of
|
|
various Builder API methods. So its not required to use the generated code, but
|
|
it does make things much simpler and compact.
|
|
|
|
Just like the `CreateString` methods, the table serialization functions return
|
|
an offset to the location of the serialized `Weapon` table.
|
|
|
|
Now that we have some `Weapons` serialized, we can serialize a `Monster`.
|
|
Looking at the schema again, this table has a lot more fields of various types.
|
|
Some of these need to be serialized beforehand, for the same reason we
|
|
serialized the name string before the weapon table.
|
|
|
|
!!! note inline end
|
|
|
|
There is no prescribed ordering of which table fields must be serialized
|
|
first, you could serialize in any order you want. You can also not serialize
|
|
a field to provide a `null` value, this is done by using an 0 offset value.
|
|
|
|
```c title="monster.fbs" linenums="15"
|
|
table Monster {
|
|
pos:Vec3;
|
|
mana:short = 150;
|
|
hp:short = 100;
|
|
name:string;
|
|
friendly:bool = false (deprecated);
|
|
inventory:[ubyte];
|
|
color:Color = Blue;
|
|
weapons:[Weapon];
|
|
equipped:Equipment;
|
|
path:[Vec3];
|
|
}
|
|
```
|
|
|
|
#### Vectors
|
|
|
|
The `weapons` field is a `vector` of `Weapon` tables. We already have two
|
|
`Weapons` serialized, so we just need to serialize a `vector` of those offsets.
|
|
The Builder provides multiple ways to create `vectors`.
|
|
|
|
=== "C++"
|
|
|
|
```c++
|
|
// Create a std::vector of the offsets we had previous made.
|
|
std::vector<flatbuffers::Offset<Weapon>> weapons_vector;
|
|
weapons_vector.push_back(sword);
|
|
weapons_vector.push_back(axe);
|
|
|
|
// Then serialize that std::vector into the buffer and again get an Offset
|
|
// to that vector. Use `auto` here since the full type is long, and it just
|
|
// a "typed" number.
|
|
auto weapons = builder.CreateVector(weapons_vector);
|
|
```
|
|
|
|
=== "C"
|
|
|
|
```c
|
|
// We use the internal builder stack to implement a dynamic vector.
|
|
ns(Weapon_vec_start(B));
|
|
ns(Weapon_vec_push(B, sword));
|
|
ns(Weapon_vec_push(B, axe));
|
|
ns(Weapon_vec_ref_t) weapons = ns(Weapon_vec_end(B));
|
|
```
|
|
|
|
=== "C#"
|
|
|
|
```c#
|
|
// Create an array of the two weapon offsets.
|
|
var weaps = new Offset<Weapon>[2];
|
|
weaps[0] = sword;
|
|
weaps[1] = axe;
|
|
|
|
// Pass the `weaps` array into the `CreateWeaponsVector()` method to create
|
|
// a FlatBuffer vector.
|
|
var weapons = Monster.CreateWeaponsVector(builder, weaps);
|
|
```
|
|
|
|
=== "Dart"
|
|
|
|
```dart
|
|
// If using the Builder classes, serialize the `[sword,axe]`
|
|
final weapons = builder.writeList([sword, axe]);
|
|
|
|
// If using the ObjectBuilders, just create an array from the two `Weapon`s
|
|
final List<myGame.WeaponBuilder> weaps = [sword, axe];
|
|
```
|
|
|
|
=== "Go"
|
|
|
|
```go
|
|
// Create a FlatBuffer vector and prepend the weapons.
|
|
// Note: Since we prepend the data, prepend them in reverse order.
|
|
sample.MonsterStartWeaponsVector(builder, 2)
|
|
builder.PrependUOffsetT(axe)
|
|
builder.PrependUOffsetT(sword)
|
|
weapons := builder.EndVector(2)
|
|
```
|
|
|
|
=== "Java"
|
|
|
|
```java
|
|
// Place the two weapons into an array, and pass it to the
|
|
// `createWeaponsVector()` method to create a FlatBuffer vector.
|
|
int[] weaps = new int[2];
|
|
weaps[0] = sword;
|
|
weaps[1] = axe;
|
|
|
|
// Pass the `weaps` array into the `createWeaponsVector()` method to create
|
|
// a FlatBuffer vector.
|
|
int weapons = Monster.createWeaponsVector(builder, weaps);
|
|
```
|
|
|
|
=== "JavaScript"
|
|
|
|
```javascript
|
|
// Create an array from the two `Weapon`s and pass it to the
|
|
// `createWeaponsVector()` method to create a FlatBuffer vector.
|
|
var weaps = [sword, axe];
|
|
var weapons = MyGame.Sample.Monster.createWeaponsVector(builder, weaps);
|
|
```
|
|
|
|
=== "Kotlin"
|
|
|
|
```kotlin
|
|
// Place the two weapons into an array, and pass it to the
|
|
// `createWeaponsVector()` method to create a FlatBuffer vector.
|
|
val weaps = intArrayOf(sword, axe)
|
|
|
|
// Pass the `weaps` array into the `createWeaponsVector()` method to create
|
|
// a FlatBuffer vector.
|
|
val weapons = Monster.createWeaponsVector(builder, weaps)
|
|
```
|
|
|
|
=== "Lobster"
|
|
|
|
```lobster
|
|
let weapons = builder.MyGame_Sample_MonsterCreateWeaponsVector([sword, axe])
|
|
```
|
|
|
|
=== "Lua"
|
|
|
|
```lua
|
|
-- Create a FlatBuffer vector and prepend the weapons.
|
|
-- Note: Since we prepend the data, prepend them in reverse order.
|
|
monster.StartWeaponsVector(builder, 2)
|
|
builder:PrependUOffsetTRelative(axe)
|
|
builder:PrependUOffsetTRelative(sword)
|
|
local weapons = builder:EndVector(2)
|
|
```
|
|
|
|
=== "PHP"
|
|
|
|
```php
|
|
// Create an array from the two `Weapon`s and pass it to the
|
|
// `CreateWeaponsVector()` method to create a FlatBuffer vector.
|
|
$weaps = array($sword, $axe);
|
|
$weapons = \MyGame\Sample\Monster::CreateWeaponsVector($builder, $weaps);
|
|
```
|
|
|
|
=== "Python"
|
|
|
|
```py
|
|
# Use the generated helper to create the weapons vector from offsets.
|
|
weapons = MyGame.Sample.Monster.CreateWeaponsVector(builder, [sword, axe])
|
|
```
|
|
|
|
=== "Rust"
|
|
|
|
```rust
|
|
// Create a FlatBuffer `vector` that contains offsets to the sword and axe
|
|
// we created above.
|
|
let weapons = builder.create_vector(&[sword, axe]);
|
|
```
|
|
|
|
=== "Swift"
|
|
|
|
```swift
|
|
// Create a FlatBuffer `vector` that contains offsets to the sword and axe
|
|
// we created above.
|
|
let weaponsOffset = builder.createVector(ofOffsets: [sword, axe])
|
|
```
|
|
|
|
=== "TypeScript"
|
|
|
|
```ts
|
|
// Create an array from the two `Weapon`s and pass it to the
|
|
// `createWeaponsVector()` method to create a FlatBuffer vector.
|
|
let weaps = [sword, axe];
|
|
let weapons = MyGame.Sample.Monster.createWeaponsVector(builder, weaps);
|
|
```
|
|
|
|
|
|
While we are at it, let us serialize the other two vector fields: the
|
|
`inventory` field is just a vector of scalars, and the `path` field is a vector
|
|
of structs (which are scalar data as well). So these vectors can be serialized a
|
|
bit more directly.
|
|
|
|
=== "C++"
|
|
|
|
```c++
|
|
// Create a `vector` representing the inventory of the Orc. Each number
|
|
// could correspond to an item that can be claimed after he is slain.
|
|
unsigned char treasure[] = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9};
|
|
flatbuffers::Offset<flatbuffers::Vector<unsigned char>> inventory =
|
|
builder.CreateVector(treasure, 10);
|
|
|
|
// Construct an array of two `Vec3` structs.
|
|
Vec3 points[] = { Vec3(1.0f, 2.0f, 3.0f), Vec3(4.0f, 5.0f, 6.0f) };
|
|
|
|
// Serialize it as a vector of structs.
|
|
flatbuffers::Offset<flatbuffers::Vector<Vec3>> path =
|
|
builder.CreateVectorOfStructs(points, 2);
|
|
```
|
|
|
|
=== "C"
|
|
|
|
```c
|
|
// Create a `vector` representing the inventory of the Orc. Each number
|
|
// could correspond to an item that can be claimed after he is slain.
|
|
uint8_t treasure[] = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9};
|
|
flatbuffers_uint8_vec_ref_t inventory;
|
|
// `c_vec_len` is the convenience macro we defined earlier.
|
|
inventory = flatbuffers_uint8_vec_create(B, treasure, c_vec_len(treasure));
|
|
```
|
|
|
|
=== "C#"
|
|
|
|
```c#
|
|
// Create a `vector` representing the inventory of the Orc. Each number
|
|
// could correspond to an item that can be claimed after he is slain.
|
|
// Note: Since we prepend the bytes, this loop iterates in reverse order.
|
|
Monster.StartInventoryVector(builder, 10);
|
|
for (int i = 9; i >= 0; i--)
|
|
{
|
|
builder.AddByte((byte)i);
|
|
}
|
|
Offset<Vector<byte>> inventory = builder.EndVector();
|
|
|
|
// Start building a path vector of length 2.
|
|
Monster.StartPathVector(fbb, 2);
|
|
|
|
// Serialize the individual Vec3 structs
|
|
Vec3.CreateVec3(builder, 1.0f, 2.0f, 3.0f);
|
|
Vec3.CreateVec3(builder, 4.0f, 5.0f, 6.0f);
|
|
|
|
// End the vector to get the offset
|
|
Offset<Vector<Vec3>> path = fbb.EndVector();
|
|
```
|
|
|
|
=== "Dart"
|
|
|
|
```dart
|
|
// Create a list representing the inventory of the Orc. Each number
|
|
// could correspond to an item that can be claimed after he is slain.
|
|
final List<int> treasure = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9];
|
|
final inventory = builder.writeListUint8(treasure);
|
|
|
|
// Using the Builder classes, you can write a list of structs like so:
|
|
// Note that the intended order should be reversed if order is important.
|
|
final vec3Builder = new myGame.Vec3Builder(builder);
|
|
vec3Builder.finish(4.0, 5.0, 6.0);
|
|
vec3Builder.finish(1.0, 2.0, 3.0);
|
|
final int path = builder.endStructVector(2); // the length of the vector
|
|
```
|
|
|
|
=== "Go"
|
|
|
|
```go
|
|
// Create a `vector` representing the inventory of the Orc. Each number
|
|
// could correspond to an item that can be claimed after he is slain.
|
|
// Note: Since we prepend the bytes, this loop iterates in reverse.
|
|
sample.MonsterStartInventoryVector(builder, 10)
|
|
for i := 9; i >= 0; i-- {
|
|
builder.PrependByte(byte(i))
|
|
}
|
|
inv := builder.EndVector(10)
|
|
|
|
sample.MonsterStartPathVector(builder, 2)
|
|
sample.CreateVec3(builder, 1.0, 2.0, 3.0)
|
|
sample.CreateVec3(builder, 4.0, 5.0, 6.0)
|
|
path := builder.EndVector(2)
|
|
```
|
|
|
|
=== "Java"
|
|
|
|
```java
|
|
// Create a `vector` representing the inventory of the Orc. Each number
|
|
// could correspond to an item that can be claimed after he is slain.
|
|
byte[] treasure = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9};
|
|
int inv = Monster.createInventoryVector(builder, treasure);
|
|
|
|
Monster.startPathVector(fbb, 2);
|
|
Vec3.createVec3(builder, 1.0f, 2.0f, 3.0f);
|
|
Vec3.createVec3(builder, 4.0f, 5.0f, 6.0f);
|
|
int path = fbb.endVector();
|
|
```
|
|
|
|
=== "JavaScript"
|
|
|
|
```javascript
|
|
// Create a `vector` representing the inventory of the Orc. Each number
|
|
// could correspond to an item that can be claimed after he is slain.
|
|
var treasure = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9];
|
|
var inv = MyGame.Sample.Monster.createInventoryVector(builder, treasure);
|
|
|
|
MyGame.Sample.Monster.startPathVector(builder, 2);
|
|
MyGame.Sample.Vec3.createVec3(builder, 1.0, 2.0, 3.0);
|
|
MyGame.Sample.Vec3.createVec3(builder, 4.0, 5.0, 6.0);
|
|
var path = builder.endVector();
|
|
```
|
|
|
|
=== "Kotlin"
|
|
|
|
```kotlin
|
|
// Create a `vector` representing the inventory of the Orc. Each number
|
|
// could correspond to an item that can be claimed after he is slain.
|
|
val treasure = byteArrayOf(0, 1, 2, 3, 4, 5, 6, 7, 8, 9)
|
|
val inv = Monster.createInventoryVector(builder, treasure)
|
|
|
|
Monster.startPathVector(fbb, 2)
|
|
Vec3.createVec3(builder, 1.0f, 2.0f, 3.0f)
|
|
Vec3.createVec3(builder, 4.0f, 5.0f, 6.0f)
|
|
val path = fbb.endVector()
|
|
```
|
|
|
|
=== "Lobster"
|
|
|
|
```lobster
|
|
// Inventory.
|
|
let inv = builder.MyGame_Sample_MonsterCreateInventoryVector(map(10): _)
|
|
|
|
builder.MyGame_Sample_MonsterStartPathVector(2)
|
|
builder.MyGame_Sample_CreateVec3(1.0, 2.0, 3.0)
|
|
builder.MyGame_Sample_CreateVec3(4.0, 5.0, 6.0)
|
|
let path = builder.EndVector(2)
|
|
```
|
|
|
|
=== "Lua"
|
|
|
|
```lua
|
|
-- Create a `vector` representing the inventory of the Orc. Each number
|
|
-- could correspond to an item that can be claimed after he is slain.
|
|
-- Note: Since we prepend the bytes, this loop iterates in reverse.
|
|
monster.StartInventoryVector(builder, 10)
|
|
for i=10,1,-1 do
|
|
builder:PrependByte(i)
|
|
end
|
|
local inv = builder:EndVector(10)
|
|
|
|
-- Create a FlatBuffer vector and prepend the path locations.
|
|
-- Note: Since we prepend the data, prepend them in reverse order.
|
|
monster.StartPathVector(builder, 2)
|
|
vec3.CreateVec3(builder, 1.0, 2.0, 3.0)
|
|
vec3.CreateVec3(builder, 4.0, 5.0, 6.0)
|
|
local path = builder:EndVector(2)
|
|
```
|
|
|
|
=== "PHP"
|
|
|
|
```php
|
|
// Create a `vector` representing the inventory of the Orc. Each number
|
|
// could correspond to an item that can be claimed after he is slain.
|
|
$treasure = array(0, 1, 2, 3, 4, 5, 6, 7, 8, 9);
|
|
$inv = \MyGame\Sample\Monster::CreateInventoryVector($builder, $treasure);
|
|
|
|
\MyGame\Example\Monster::StartPathVector($builder, 2);
|
|
\MyGame\Sample\Vec3::CreateVec3($builder, 1.0, 2.0, 3.0);
|
|
\MyGame\Sample\Vec3::CreateVec3($builder, 1.0, 2.0, 3.0);
|
|
$path = $builder->endVector();
|
|
```
|
|
|
|
=== "Python"
|
|
|
|
```py
|
|
# Create a `vector` representing the inventory of the Orc. Each number
|
|
# could correspond to an item that can be claimed after he is slain.
|
|
inv = MyGame.Sample.Monster.CreateInventoryVector(builder, range(0, 10))
|
|
|
|
path_points = [
|
|
MyGame.Sample.Vec3T(x=1.0, y=2.0, z=3.0),
|
|
MyGame.Sample.Vec3T(x=4.0, y=5.0, z=6.0),
|
|
]
|
|
path = MyGame.Sample.Monster.CreatePathVector(builder, path_points)
|
|
```
|
|
|
|
=== "Rust"
|
|
|
|
```rust
|
|
// Inventory.
|
|
let inventory = builder.create_vector(&[0u8, 1, 2, 3, 4, 5, 6, 7, 8, 9]);
|
|
|
|
// Create the path vector of Vec3 objects.
|
|
let x = Vec3::new(1.0, 2.0, 3.0);
|
|
let y = Vec3::new(4.0, 5.0, 6.0);
|
|
let path = builder.create_vector(&[x, y]);
|
|
```
|
|
|
|
=== "Swift"
|
|
|
|
```swift
|
|
// create inventory
|
|
let inventory: [Byte] = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
|
|
let inventoryOffset = builder.createVector(inventory)
|
|
|
|
let path = fbb.createVector(ofStructs: [
|
|
Vec3(x: 1, y: 2, z: 3),
|
|
Vec3(x: 4, y: 5, z: 6)
|
|
])
|
|
```
|
|
|
|
=== "TypeScript"
|
|
|
|
```ts
|
|
// Create a `vector` representing the inventory of the Orc. Each number
|
|
// could correspond to an item that can be claimed after he is slain.
|
|
let treasure = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9];
|
|
let inv = MyGame.Sample.Monster.createInventoryVector(builder, treasure);
|
|
|
|
MyGame.Sample.Monster.startPathVector(builder, 2);
|
|
MyGame.Sample.Vec3.createVec3(builder, 1.0, 2.0, 3.0);
|
|
MyGame.Sample.Vec3.createVec3(builder, 4.0, 5.0, 6.0);
|
|
let path = builder.endVector();
|
|
```
|
|
|
|
|
|
#### Unions
|
|
|
|
The last non-scalar data field for the `Monster` table is the `equipped` `union`
|
|
field. For this case, we will reuse an already serialized `Weapon` (the only
|
|
type in the union), without needing to reserialize it. Union fields implicitly
|
|
add a hidden `_type` field that stores the type of value stored in the union.
|
|
When serializing a union, you must explicitly set this type field, along with
|
|
providing the union value.
|
|
|
|
We will also serialize the other scalar data at the same time, since we have all
|
|
the necessary values and Offsets to make a `Monster`.
|
|
|
|
=== "C++"
|
|
|
|
```c++
|
|
// Create the remaining data needed for the Monster.
|
|
auto name = builder.CreateString("Orc");
|
|
|
|
// Create the position struct
|
|
auto position = Vec3(1.0f, 2.0f, 3.0f);
|
|
|
|
// Set his hit points to 300 and his mana to 150.
|
|
int hp = 300;
|
|
int mana = 150;
|
|
|
|
// Finally, create the monster using the `CreateMonster` helper function
|
|
// to set all fields.
|
|
//
|
|
// Here we set the union field by using the `.Union()` method of the
|
|
// `Offset<Weapon>` axe we already serialized above. We just have to specify
|
|
// which type of object we put in the union, and do that with the
|
|
// auto-generated `Equipment_Weapon` enum.
|
|
flatbuffers::Offset<Monster> orc =
|
|
CreateMonster(builder, &position, mana, hp, name, inventory,
|
|
Color_Red, weapons, Equipment_Weapon, axe.Union(),
|
|
path);
|
|
|
|
```
|
|
|
|
=== "C"
|
|
|
|
```c
|
|
// Serialize a name for our monster, called "Orc".
|
|
// The _str suffix indicates the source is an ascii-z string.
|
|
flatbuffers_string_ref_t name = flatbuffers_string_create_str(B, "Orc");
|
|
|
|
// Set his hit points to 300 and his mana to 150.
|
|
uint16_t hp = 300;
|
|
uint16_t mana = 150;
|
|
|
|
// Define an equipment union. `create` calls in C has a single
|
|
// argument for unions where C++ has both a type and a data argument.
|
|
ns(Equipment_union_ref_t) equipped = ns(Equipment_as_Weapon(axe));
|
|
ns(Vec3_t) pos = { 1.0f, 2.0f, 3.0f };
|
|
ns(Monster_create_as_root(B, &pos, mana, hp, name, inventory, ns(Color_Red),
|
|
weapons, equipped, path));
|
|
```
|
|
|
|
=== "C#"
|
|
|
|
```c#
|
|
// Create the remaining data needed for the Monster.
|
|
var name = builder.CreateString("Orc");
|
|
|
|
// Create our monster using `StartMonster()` and `EndMonster()`.
|
|
Monster.StartMonster(builder);
|
|
Monster.AddPos(builder, Vec3.CreateVec3(builder, 1.0f, 2.0f, 3.0f));
|
|
Monster.AddHp(builder, (short)300);
|
|
Monster.AddName(builder, name);
|
|
Monster.AddInventory(builder, inv);
|
|
Monster.AddColor(builder, Color.Red);
|
|
Monster.AddWeapons(builder, weapons);
|
|
// For union fields, we explicitly add the auto-generated enum for the type
|
|
// of value stored in the union.
|
|
Monster.AddEquippedType(builder, Equipment.Weapon);
|
|
// And we just use the `.Value` property of the already serialized axe.
|
|
Monster.AddEquipped(builder, axe.Value); // Axe
|
|
Monster.AddPath(builder, path);
|
|
Offset<Monster> orc = Monster.EndMonster(builder);
|
|
```
|
|
|
|
=== "Dart"
|
|
|
|
```dart
|
|
// Serialize a name for our monster, called "Orc".
|
|
final int name = builder.writeString('Orc');
|
|
|
|
// Using the Builder API:
|
|
// Set his hit points to 300 and his mana to 150.
|
|
final int hp = 300;
|
|
final int mana = 150;
|
|
|
|
final monster = new myGame.MonsterBuilder(builder)
|
|
..begin()
|
|
..addNameOffset(name)
|
|
..addInventoryOffset(inventory)
|
|
..addWeaponsOffset(weapons)
|
|
..addEquippedType(myGame.EquipmentTypeId.Weapon)
|
|
..addEquippedOffset(axe)
|
|
..addHp(hp)
|
|
..addMana(mana)
|
|
..addPos(vec3Builder.finish(1.0, 2.0, 3.0))
|
|
..addPathOffset(path)
|
|
..addColor(myGame.Color.Red);
|
|
|
|
final int orc = monster.finish();
|
|
```
|
|
|
|
=== "Go"
|
|
|
|
```go
|
|
// Serialize a name for our monster, called "Orc".
|
|
name := builder.CreateString("Orc")
|
|
|
|
// Create our monster using `MonsterStart()` and `MonsterEnd()`.
|
|
sample.MonsterStart(builder)
|
|
sample.MonsterAddPos(builder, sample.CreateVec3(builder, 1.0, 2.0, 3.0))
|
|
sample.MonsterAddHp(builder, 300)
|
|
sample.MonsterAddName(builder, name)
|
|
sample.MonsterAddInventory(builder, inv)
|
|
sample.MonsterAddColor(builder, sample.ColorRed)
|
|
sample.MonsterAddWeapons(builder, weapons)
|
|
sample.MonsterAddEquippedType(builder, sample.EquipmentWeapon)
|
|
sample.MonsterAddEquipped(builder, axe)
|
|
sample.MonsterAddPath(builder, path)
|
|
orc := sample.MonsterEnd(builder)
|
|
```
|
|
|
|
=== "Java"
|
|
|
|
```java
|
|
// Serialize a name for our monster, called "Orc".
|
|
int name = builder.createString("Orc");
|
|
|
|
// Create our monster using `startMonster()` and `endMonster()`.
|
|
Monster.startMonster(builder);
|
|
Monster.addPos(builder, Vec3.createVec3(builder, 1.0f, 2.0f, 3.0f));
|
|
Monster.addName(builder, name);
|
|
Monster.addColor(builder, Color.Red);
|
|
Monster.addHp(builder, (short)300);
|
|
Monster.addInventory(builder, inv);
|
|
Monster.addWeapons(builder, weapons);
|
|
Monster.addEquippedType(builder, Equipment.Weapon);
|
|
Monster.addEquipped(builder, axe);
|
|
Monster.addPath(builder, path);
|
|
int orc = Monster.endMonster(builder);
|
|
```
|
|
|
|
=== "JavaScript"
|
|
|
|
```javascript
|
|
// Serialize a name for our monster, called 'Orc'.
|
|
var name = builder.createString('Orc');
|
|
|
|
// Create our monster by using `startMonster()` and `endMonster()`.
|
|
MyGame.Sample.Monster.startMonster(builder);
|
|
MyGame.Sample.Monster.addPos(builder,
|
|
MyGame.Sample.Vec3.createVec3(builder, 1.0, 2.0, 3.0));
|
|
MyGame.Sample.Monster.addHp(builder, 300);
|
|
MyGame.Sample.Monster.addColor(builder, MyGame.Sample.Color.Red)
|
|
MyGame.Sample.Monster.addName(builder, name);
|
|
MyGame.Sample.Monster.addInventory(builder, inv);
|
|
MyGame.Sample.Monster.addWeapons(builder, weapons);
|
|
MyGame.Sample.Monster.addEquippedType(builder,
|
|
MyGame.Sample.Equipment.Weapon);
|
|
MyGame.Sample.Monster.addEquipped(builder, axe);
|
|
MyGame.Sample.Monster.addPath(builder, path);
|
|
var orc = MyGame.Sample.Monster.endMonster(builder);
|
|
```
|
|
|
|
=== "Kotlin"
|
|
|
|
```kotlin
|
|
// Serialize a name for our monster, called "Orc".
|
|
val name = builder.createString("Orc")
|
|
|
|
// Create our monster using `startMonster()` and `endMonster()`.
|
|
Monster.startMonster(builder)
|
|
Monster.addPos(builder, Vec3.createVec3(builder, 1.0f, 2.0f, 3.0f))
|
|
Monster.addName(builder, name)
|
|
Monster.addColor(builder, Color.Red)
|
|
Monster.addHp(builder, 300.toShort())
|
|
Monster.addInventory(builder, inv)
|
|
Monster.addWeapons(builder, weapons)
|
|
Monster.addEquippedType(builder, Equipment.Weapon)
|
|
Monster.addEquipped(builder, axe)
|
|
Monster.addPath(builder, path)
|
|
val orc = Monster.endMonster(builder)
|
|
```
|
|
|
|
=== "Lobster"
|
|
|
|
```lobster
|
|
// Name of the monster.
|
|
let name = builder.CreateString("Orc")
|
|
|
|
let orc = MyGame_Sample_MonsterBuilder { b }
|
|
.start()
|
|
.add_pos(b.MyGame_Sample_CreateVec3(1.0, 2.0, 3.0))
|
|
.add_hp(300)
|
|
.add_name(name)
|
|
.add_inventory(inv)
|
|
.add_color(MyGame_Sample_Color_Red)
|
|
.add_weapons(weapons)
|
|
.add_equipped_type(MyGame_Sample_Equipment_Weapon)
|
|
.add_equipped(weapon_offsets[1])
|
|
.add_path(path)
|
|
.end()
|
|
```
|
|
|
|
=== "Lua"
|
|
|
|
```lua
|
|
-- Serialize a name for our monster, called 'orc'
|
|
local name = builder:CreateString("Orc")
|
|
|
|
-- Create our monster by using Start() andEnd()
|
|
monster.Start(builder)
|
|
monster.AddPos(builder, vec3.CreateVec3(builder, 1.0, 2.0, 3.0))
|
|
monster.AddHp(builder, 300)
|
|
monster.AddName(builder, name)
|
|
monster.AddInventory(builder, inv)
|
|
monster.AddColor(builder, color.Red)
|
|
monster.AddWeapons(builder, weapons)
|
|
monster.AddEquippedType(builder, equipment.Weapon)
|
|
monster.AddEquipped(builder, axe)
|
|
monster.AddPath(builder, path)
|
|
local orc = monster.End(builder)
|
|
```
|
|
|
|
=== "PHP"
|
|
|
|
```php
|
|
// Serialize a name for our monster, called "Orc".
|
|
$name = $builder->createString("Orc");
|
|
|
|
// Create our monster by using `StartMonster()` and `EndMonster()`.
|
|
\MyGame\Sample\Monster::StartMonster($builder);
|
|
\MyGame\Sample\Monster::AddPos($builder,
|
|
\MyGame\Sample\Vec3::CreateVec3($builder, 1.0, 2.0, 3.0));
|
|
\MyGame\Sample\Monster::AddHp($builder, 300);
|
|
\MyGame\Sample\Monster::AddName($builder, $name);
|
|
\MyGame\Sample\Monster::AddInventory($builder, $inv);
|
|
\MyGame\Sample\Monster::AddColor($builder, \MyGame\Sample\Color::Red);
|
|
\MyGame\Sample\Monster::AddWeapons($builder, $weapons);
|
|
\MyGame\Sample\Monster::AddEquippedType($builder,
|
|
\MyGame\Sample\Equipment::Weapon);
|
|
\MyGame\Sample\Monster::AddEquipped($builder, $axe);
|
|
\MyGame\Sample\Monster::AddPath($builder, $path);
|
|
$orc = \MyGame\Sample\Monster::EndMonster($builder);
|
|
```
|
|
|
|
=== "Python"
|
|
|
|
```py
|
|
# Serialize a name for our monster, called "Orc".
|
|
name = builder.CreateString("Orc")
|
|
|
|
# Create our monster by using `Monster.Start()` and `Monster.End()`.
|
|
MyGame.Sample.Monster.Start(builder)
|
|
MyGame.Sample.Monster.AddPos(builder,
|
|
MyGame.Sample.Vec3.CreateVec3(builder, 1.0, 2.0, 3.0))
|
|
MyGame.Sample.Monster.AddHp(builder, 300)
|
|
MyGame.Sample.Monster.AddName(builder, name)
|
|
MyGame.Sample.Monster.AddInventory(builder, inv)
|
|
MyGame.Sample.Monster.AddColor(builder,
|
|
MyGame.Sample.Color.Color().Red)
|
|
MyGame.Sample.Monster.AddWeapons(builder, weapons)
|
|
MyGame.Sample.Monster.AddEquippedType(
|
|
builder, MyGame.Sample.Equipment.Equipment().Weapon)
|
|
MyGame.Sample.Monster.AddEquipped(builder, axe)
|
|
MyGame.Sample.Monster.AddPath(builder, path)
|
|
orc = MyGame.Sample.Monster.End(builder)
|
|
```
|
|
|
|
=== "Rust"
|
|
|
|
```rust
|
|
// Name of the Monster.
|
|
let name = builder.create_string("Orc");
|
|
|
|
// Create the monster using the `Monster::create` helper function. This
|
|
// function accepts a `MonsterArgs` struct, which supplies all of the data
|
|
// needed to build a `Monster`. To supply empty/default fields, just use the
|
|
// Rust built-in `Default::default()` function, as demonstrated below.
|
|
let orc = Monster::create(&mut builder, &MonsterArgs{
|
|
pos: Some(&Vec3::new(1.0f32, 2.0f32, 3.0f32)),
|
|
mana: 150,
|
|
hp: 80,
|
|
name: Some(name),
|
|
inventory: Some(inventory),
|
|
color: Color::Red,
|
|
weapons: Some(weapons),
|
|
equipped_type: Equipment::Weapon,
|
|
equipped: Some(axe.as_union_value()),
|
|
path: Some(path),
|
|
..Default::default()
|
|
});
|
|
```
|
|
|
|
=== "Swift"
|
|
|
|
```swift
|
|
// Name of the Monster.
|
|
let name = builder.create(string: "Orc")
|
|
|
|
let orc = Monster.createMonster(
|
|
&builder,
|
|
pos: MyGame_Sample_Vec3(x: 1, y: 2, z: 3),
|
|
hp: 300,
|
|
nameOffset: name,
|
|
inventoryVectorOffset: inventoryOffset,
|
|
color: .red,
|
|
weaponsVectorOffset: weaponsOffset,
|
|
equippedType: .weapon,
|
|
equippedOffset: axe)
|
|
```
|
|
|
|
=== "TypeScript"
|
|
|
|
```ts
|
|
// Serialize a name for our monster, called 'Orc'.
|
|
let name = builder.createString('Orc');
|
|
|
|
// Create our monster by using `startMonster()` and `endMonster()`.
|
|
MyGame.Sample.Monster.startMonster(builder);
|
|
MyGame.Sample.Monster.addPos(builder,
|
|
MyGame.Sample.Vec3.createVec3(builder, 1.0, 2.0, 3.0));
|
|
MyGame.Sample.Monster.addHp(builder, 300);
|
|
MyGame.Sample.Monster.addColor(builder, MyGame.Sample.Color.Red)
|
|
MyGame.Sample.Monster.addName(builder, name);
|
|
MyGame.Sample.Monster.addInventory(builder, inv);
|
|
MyGame.Sample.Monster.addWeapons(builder, weapons);
|
|
MyGame.Sample.Monster.addEquippedType(builder,
|
|
MyGame.Sample.Equipment.Weapon);
|
|
MyGame.Sample.Monster.addEquipped(builder, axe);
|
|
MyGame.Sample.Monster.addPath(builder, path);
|
|
let orc = MyGame.Sample.Monster.endMonster(builder);
|
|
```
|
|
|
|
|
|
### Finishing
|
|
|
|
At this point, we have serialized a `Monster` we've named "orc" to the
|
|
flatbuffer and have its offset. The `root_type` of the schema is also a
|
|
`Monster`, so we have everything we need to finish the serialization step.
|
|
|
|
This is done by calling the appropriate `finish` method on the Builder, passing
|
|
in the orc offset to indicate this `table` is the "entry" point when
|
|
deserializing the buffer later.
|
|
|
|
=== "C++"
|
|
|
|
```c++
|
|
// Call `Finish()` to instruct the builder that this monster is complete.
|
|
// You could also call `FinishMonsterBuffer(builder, orc);`
|
|
builder.Finish(orc);
|
|
```
|
|
|
|
=== "C"
|
|
|
|
```c
|
|
// Because we used `Monster_create_as_root`, we do not need a `finish` call
|
|
// in C.
|
|
```
|
|
|
|
=== "C#"
|
|
|
|
```c#
|
|
// Call `Finish()` to instruct the builder that this monster is complete.
|
|
// You could also call `Monster.FinishMonsterBuffer(builder, orc);`
|
|
builder.Finish(orc.Value);
|
|
```
|
|
|
|
=== "Dart"
|
|
|
|
```dart
|
|
// Call `finish()` to instruct the builder that this monster is complete.
|
|
// See the next code section, as in Dart `finish` will also return the byte
|
|
// array.
|
|
```
|
|
|
|
=== "Go"
|
|
|
|
```go
|
|
// Call `Finish()` to instruct the builder that this monster is complete.
|
|
builder.Finish(orc)
|
|
```
|
|
|
|
=== "Java"
|
|
|
|
```java
|
|
// Call `finish()` to instruct the builder that this monster is complete.
|
|
builder.finish(orc);
|
|
```
|
|
|
|
=== "JavaScript"
|
|
|
|
```javascript
|
|
// Call `finish()` to instruct the builder that this monster is complete.
|
|
builder.finish(orc);
|
|
```
|
|
|
|
=== "Kotlin"
|
|
|
|
```kotlin
|
|
// Call `finish()` to instruct the builder that this monster is complete.
|
|
builder.finish(orc) ;
|
|
```
|
|
|
|
=== "Lobster"
|
|
|
|
```lobster
|
|
// Call `Finish()` to instruct the builder that this monster is complete.
|
|
builder.Finish(orc)
|
|
```
|
|
|
|
=== "Lua"
|
|
|
|
```lua
|
|
-- Call 'Finish()' to instruct the builder that this monster is complete.
|
|
builder:Finish(orc)
|
|
```
|
|
|
|
=== "PHP"
|
|
|
|
```php
|
|
// Call `finish()` to instruct the builder that this monster is complete.
|
|
$builder->finish($orc);
|
|
```
|
|
|
|
=== "Python"
|
|
|
|
```py
|
|
# Call `Finish()` to instruct the builder that this monster is complete.
|
|
builder.Finish(orc)
|
|
```
|
|
|
|
=== "Rust"
|
|
|
|
```rust
|
|
// Call `finish()` to instruct the builder that this monster is complete.
|
|
builder.finish(orc, None);
|
|
```
|
|
|
|
=== "Swift"
|
|
|
|
```swift
|
|
// Call `finish()` to instruct the builder that this monster is complete.
|
|
builder.finish(offset: orc)
|
|
```
|
|
|
|
=== "TypeScript"
|
|
|
|
```ts
|
|
// Call `finish()` to instruct the builder that this monster is complete.
|
|
builder.finish(orc);
|
|
```
|
|
|
|
|
|
Once you finish a Builder, you can no longer serialize more data to it.
|
|
|
|
#### Buffer Access
|
|
|
|
The flatbuffer is now ready to be stored somewhere, sent over the network,
|
|
compressed, or whatever you would like to do with it. You access the raw buffer
|
|
like so:
|
|
|
|
=== "C++"
|
|
|
|
```c++
|
|
// This must be called after `Finish()`.
|
|
uint8_t *buf = builder.GetBufferPointer();
|
|
|
|
// Returns the size of the buffer that `GetBufferPointer()` points to.
|
|
int size = builder.GetSize();
|
|
```
|
|
|
|
=== "C"
|
|
|
|
```c
|
|
uint8_t *buf;
|
|
size_t size;
|
|
|
|
// Allocate and extract a readable buffer from internal builder heap.
|
|
// The returned buffer must be deallocated using `free`.
|
|
// NOTE: Finalizing the buffer does NOT change the builder, it
|
|
// just creates a snapshot of the builder content.
|
|
buf = flatcc_builder_finalize_buffer(B, &size);
|
|
// use buf
|
|
free(buf);
|
|
|
|
// Optionally reset builder to reuse builder without deallocating
|
|
// internal stack and heap.
|
|
flatcc_builder_reset(B);
|
|
// build next buffer.
|
|
// ...
|
|
|
|
// Cleanup.
|
|
flatcc_builder_clear(B);
|
|
```
|
|
|
|
=== "C#"
|
|
|
|
```c#
|
|
// This must be called after `Finish()`.
|
|
//
|
|
// The data in this ByteBuffer does NOT start at 0, but at buf.Position.
|
|
// The end of the data is marked by buf.Length, so the size is
|
|
// buf.Length - buf.Position.
|
|
FlatBuffers.ByteBuffer dataBuffer = builder.DataBuffer;
|
|
|
|
// Alternatively this copies the above data out of the ByteBuffer for you:
|
|
byte[] buf = builder.SizedByteArray();
|
|
```
|
|
|
|
=== "Dart"
|
|
|
|
```dart
|
|
final Uint8List buf = builder.finish(orc);
|
|
```
|
|
|
|
=== "Go"
|
|
|
|
```go
|
|
// This must be called after `Finish()`.
|
|
buf := builder.FinishedBytes() // Of type `byte[]`.
|
|
```
|
|
|
|
=== "Java"
|
|
|
|
```java
|
|
// This must be called after `finish()`.
|
|
java.nio.ByteBuffer buf = builder.dataBuffer();
|
|
// The data in this ByteBuffer does NOT start at 0, but at buf.position().
|
|
// The number of bytes is buf.remaining().
|
|
|
|
// Alternatively this copies the above data out of the ByteBuffer for you:
|
|
byte[] buf = builder.sizedByteArray();
|
|
```
|
|
|
|
=== "JavaScript"
|
|
|
|
```javascript
|
|
// This must be called after `finish()`.
|
|
var buf = builder.asUint8Array(); // Of type `Uint8Array`.
|
|
```
|
|
|
|
=== "Kotlin"
|
|
|
|
```kotlin
|
|
// This must be called after `finish()`.
|
|
val buf = builder.dataBuffer()
|
|
// The data in this ByteBuffer does NOT start at 0, but at buf.position().
|
|
// The number of bytes is buf.remaining().
|
|
|
|
// Alternatively this copies the above data out of the ByteBuffer for you:
|
|
val buf = builder.sizedByteArray()
|
|
```
|
|
|
|
=== "Lobster"
|
|
|
|
```lobster
|
|
// This must be called after `Finish()`.
|
|
let buf = builder.SizedCopy() // Of type `string`.
|
|
```
|
|
|
|
=== "Lua"
|
|
|
|
```lua
|
|
local bufAsString = builder:Output()
|
|
```
|
|
|
|
=== "PHP"
|
|
|
|
```php
|
|
// This must be called after `finish()`.
|
|
$buf = $builder->dataBuffer(); // Of type `Google\FlatBuffers\ByteBuffer`
|
|
// The data in this ByteBuffer does NOT start at 0, but at
|
|
// buf->getPosition().
|
|
// The end of the data is marked by buf->capacity(), so the size is
|
|
// buf->capacity() - buf->getPosition().
|
|
```
|
|
|
|
=== "Python"
|
|
|
|
```py
|
|
# This must be called after `Finish()`.
|
|
buf = builder.Output() // Of type `bytearray`.
|
|
```
|
|
|
|
=== "Rust"
|
|
|
|
```rust
|
|
// This must be called after `finish()`.
|
|
// `finished_data` returns a byte slice.
|
|
let buf = builder.finished_data(); // Of type `&[u8]`
|
|
```
|
|
|
|
=== "Swift"
|
|
|
|
```swift
|
|
// This must be called after `finish()`.
|
|
// `sizedByteArray` returns the finished buf of type [UInt8].
|
|
let buf = builder.sizedByteArray
|
|
// or you can use to get an object of type Data
|
|
let bufData = ByteBuffer(data: builder.data)
|
|
// or
|
|
let buf = builder.sizedBuffer
|
|
```
|
|
|
|
=== "TypeScript"
|
|
|
|
```ts
|
|
// This must be called after `finish()`.
|
|
let buf = builder.asUint8Array(); // Of type `Uint8Array`.
|
|
```
|
|
|
|
|
|
Now you can write the bytes to a file or send them over the network. The buffer
|
|
stays valid until the Builder is cleared or destroyed.
|
|
|
|
Make sure your file mode (or transfer protocol) is set to BINARY, and not TEXT.
|
|
If you try to transfer a flatbuffer in TEXT mode, the buffer will be corrupted
|
|
and be hard to diagnose.
|
|
|
|
## Deserialization
|
|
|
|
Deserialization is a bit of a misnomer, since FlatBuffers doesn't deserialize
|
|
the whole buffer when accessed. It just "decodes" the data that is requested,
|
|
leaving all the other data untouched. It is up to the application to decide if
|
|
the data is copied out or even read in the first place. However, we continue to
|
|
use the word `deserialize` to mean accessing data from a binary flatbuffer.
|
|
|
|
Now that we have successfully create an orc FlatBuffer, the data can be saved,
|
|
sent over a network, etc. At some point, the buffer will be accessed to obtain
|
|
the underlying data.
|
|
|
|
The same application setup used for serialization is needed for deserialization
|
|
(see [application integration](#application-integration)).
|
|
|
|
### Root Access
|
|
|
|
All access to the data in the flatbuffer must first go through the root object.
|
|
There is only one root object per flatbuffer. The generated code provides
|
|
functions to get the root object given the buffer.
|
|
|
|
=== "C++"
|
|
|
|
```c++
|
|
uint8_t *buffer_pointer = /* the data you just read */;
|
|
|
|
// Get a view to the root object inside the buffer.
|
|
Monster monster = GetMonster(buffer_pointer);
|
|
```
|
|
|
|
=== "C"
|
|
|
|
```c
|
|
// Note that we use the `table_t` suffix when reading a table object
|
|
// as opposed to the `ref_t` suffix used during the construction of
|
|
// the buffer.
|
|
ns(Monster_table_t) monster = ns(Monster_as_root(buffer));
|
|
|
|
// Note: root object pointers are NOT the same as the `buffer` pointer.
|
|
```
|
|
|
|
=== "C#"
|
|
|
|
```c#
|
|
byte[] bytes = /* the data you just read */
|
|
|
|
// Get a view to the root object inside the buffer.
|
|
Monster monster = Monster.GetRootAsMonster(new ByteBuffer(bytes));
|
|
```
|
|
|
|
=== "Dart"
|
|
|
|
```dart
|
|
List<int> data = ... // the data, e.g. from file or network
|
|
// A generated factory constructor that will read the data.
|
|
myGame.Monster monster = new myGame.Monster(data);
|
|
```
|
|
|
|
=== "Go"
|
|
|
|
```go
|
|
var buf []byte = /* the data you just read */
|
|
|
|
// Get an accessor to the root object inside the buffer.
|
|
monster := sample.GetRootAsMonster(buf, 0)
|
|
|
|
// Note: We use `0` for the offset here, which is typical for most buffers
|
|
// you would read. If you wanted to read from `builder.Bytes` directly, you
|
|
// would need to pass in the offset of `builder.Head()`, as the builder
|
|
// constructs the buffer backwards, so may not start at offset 0.
|
|
```
|
|
|
|
=== "Java"
|
|
|
|
```java
|
|
byte[] bytes = /* the data you just read */
|
|
java.nio.ByteBuffer buf = java.nio.ByteBuffer.wrap(bytes);
|
|
|
|
// Get an accessor to the root object inside the buffer.
|
|
Monster monster = Monster.getRootAsMonster(buf);
|
|
```
|
|
|
|
=== "JavaScript"
|
|
|
|
```javascript
|
|
// the data you just read, as a `Uint8Array`
|
|
// Note that the example here uses `readFileSync` from the built-in `fs`
|
|
// module, but other methods for accessing the file contents will also work.
|
|
var bytes = new Uint8Array(readFileSync('./monsterdata.bin'));
|
|
|
|
var buf = new flatbuffers.ByteBuffer(bytes);
|
|
|
|
// Get an accessor to the root object inside the buffer.
|
|
var monster = MyGame.Sample.Monster.getRootAsMonster(buf);
|
|
```
|
|
|
|
=== "Kotlin"
|
|
|
|
```kotlin
|
|
val bytes = /* the data you just read */
|
|
val buf = java.nio.ByteBuffer.wrap(bytes)
|
|
|
|
// Get an accessor to the root object inside the buffer.
|
|
Monster monster = Monster.getRootAsMonster(buf)
|
|
```
|
|
|
|
=== "Lobster"
|
|
|
|
```lobster
|
|
buf = /* the data you just read, in a string */
|
|
|
|
// Get an accessor to the root object inside the buffer.
|
|
let monster = MyGame_Sample_GetRootAsMonster(buf)
|
|
```
|
|
|
|
=== "Lua"
|
|
|
|
```lua
|
|
local bufAsString = -- The data you just read in
|
|
|
|
-- Convert the string representation into binary array Lua structure
|
|
local buf = flatbuffers.binaryArray.New(bufAsString)
|
|
|
|
-- Get an accessor to the root object insert the buffer
|
|
local mon = monster.GetRootAsMonster(buf, 0)
|
|
```
|
|
|
|
=== "PHP"
|
|
|
|
```php
|
|
$bytes = /* the data you just read, in a string */
|
|
$buf = Google\FlatBuffers\ByteBuffer::wrap($bytes);
|
|
|
|
// Get an accessor to the root object inside the buffer.
|
|
$monster = \MyGame\Sample\Monster::GetRootAsMonster($buf);
|
|
```
|
|
|
|
=== "Python"
|
|
|
|
```py
|
|
buf = /* the data you just read, in an object of type "bytearray" */
|
|
|
|
# Get an accessor to the root object inside the buffer.
|
|
monster = MyGame.Sample.Monster.Monster.GetRootAs(buf, 0)
|
|
|
|
# Note: We use `0` for the offset here, which is typical for most buffers
|
|
# you would read. If you wanted to read from the `builder.Bytes` directly,
|
|
# you would need to pass in the offset of `builder.Head()`, as the builder
|
|
# constructs the buffer backwards, so may not start at offset 0.
|
|
```
|
|
|
|
=== "Rust"
|
|
|
|
```rust
|
|
let buf = /* the data you just read, in a &[u8] */
|
|
|
|
// Get an accessor to the root object inside the buffer.
|
|
let monster = root_as_monster(buf).unwrap();
|
|
```
|
|
|
|
=== "Swift"
|
|
|
|
```swift
|
|
// create a ByteBuffer(:) from an [UInt8] or Data()
|
|
var buf = // Get your data
|
|
// Get an accessor to the root object inside the buffer.
|
|
let monster: Monster = try! getCheckedRoot(byteBuffer: &byteBuffer)
|
|
// let monster: Monster = getRoot(byteBuffer: &byteBuffer)
|
|
```
|
|
|
|
=== "TypeScript"
|
|
|
|
```ts
|
|
// the data you just read, as a `Uint8Array`.
|
|
// Note that the example here uses `readFileSync` from the built-in `fs`
|
|
// module, but other methods for accessing the file contents will also work.
|
|
let bytes = new Uint8Array(readFileSync('./monsterdata.bin'));
|
|
|
|
let buf = new flatbuffers.ByteBuffer(bytes);
|
|
|
|
// Get an accessor to the root object inside the buffer.
|
|
let monster = MyGame.Sample.Monster.getRootAsMonster(buf);
|
|
```
|
|
|
|
|
|
Again, make sure you read the bytes in BINARY mode, otherwise the buffer may be
|
|
corrupted.
|
|
|
|
In most languages, the returned object is just a "view" of the data with helpful
|
|
accessors. Data is typically not copied out of the backing buffer. This also
|
|
means the backing buffer must remain alive for the duration of the views.
|
|
|
|
### Table Access
|
|
|
|
If you look in the generated files emitted by `flatc`, you will see it generated
|
|
, for each `table`, accessors of all its non-`deprecated` fields. For example,
|
|
some of the accessors of the `Monster` root table would look like:
|
|
|
|
=== "C++"
|
|
|
|
```c++
|
|
auto hp = monster->hp();
|
|
auto mana = monster->mana();
|
|
auto name = monster->name()->c_str();
|
|
```
|
|
|
|
=== "C"
|
|
|
|
```c
|
|
uint16_t hp = ns(Monster_hp(monster));
|
|
uint16_t mana = ns(Monster_mana(monster));
|
|
flatbuffers_string_t name = ns(Monster_name(monster));
|
|
```
|
|
|
|
=== "C#"
|
|
|
|
```c#
|
|
// For C#, unlike most other languages support by FlatBuffers, most values
|
|
// (except for vectors and unions) are available as properties instead of
|
|
// accessor methods.
|
|
var hp = monster.Hp;
|
|
var mana = monster.Mana;
|
|
var name = monster.Name;
|
|
```
|
|
|
|
=== "Dart"
|
|
|
|
```dart
|
|
// For Dart, unlike other languages support by FlatBuffers, most values
|
|
// are available as properties instead of accessor methods.
|
|
var hp = monster.hp;
|
|
var mana = monster.mana;
|
|
var name = monster.name;
|
|
```
|
|
|
|
=== "Go"
|
|
|
|
```go
|
|
hp := monster.Hp()
|
|
mana := monster.Mana()
|
|
name := string(monster.Name()) // Note: `monster.Name()` returns a byte[].
|
|
```
|
|
|
|
=== "Java"
|
|
|
|
```java
|
|
short hp = monster.hp();
|
|
short mana = monster.mana();
|
|
String name = monster.name();
|
|
```
|
|
|
|
=== "JavaScript"
|
|
|
|
```javascript
|
|
var hp = monster.hp();
|
|
var mana = monster.mana();
|
|
var name = monster.name();
|
|
```
|
|
|
|
=== "Kotlin"
|
|
|
|
```kotlin
|
|
val hp = monster.hp
|
|
val mana = monster.mana
|
|
val name = monster.name
|
|
```
|
|
|
|
=== "Lobster"
|
|
|
|
```lobster
|
|
let hp = monster.hp
|
|
let mana = monster.mana
|
|
let name = monster.name
|
|
```
|
|
|
|
=== "Lua"
|
|
|
|
```lua
|
|
local hp = mon:Hp()
|
|
local mana = mon:Mana()
|
|
local name = mon:Name()
|
|
```
|
|
|
|
=== "PHP"
|
|
|
|
```php
|
|
$hp = $monster->getHp();
|
|
$mana = $monster->getMana();
|
|
$name = monster->getName();
|
|
```
|
|
|
|
=== "Python"
|
|
|
|
```py
|
|
hp = monster.Hp()
|
|
mana = monster.Mana()
|
|
name = monster.Name()
|
|
```
|
|
|
|
=== "Rust"
|
|
|
|
```rust
|
|
// Get and test some scalar types from the FlatBuffer.
|
|
let hp = monster.hp();
|
|
let mana = monster.mana();
|
|
let name = monster.name();
|
|
```
|
|
|
|
=== "Swift"
|
|
|
|
```swift
|
|
let hp = monster.hp
|
|
let mana = monster.mana
|
|
let name = monster.name // returns an optional string
|
|
```
|
|
|
|
=== "TypeScript"
|
|
|
|
```ts
|
|
let hp = monster.hp();
|
|
let mana = monster.mana();
|
|
let name = monster.name();
|
|
```
|
|
|
|
|
|
These accessors should hold the values `300`, `150`, and `"Orc"` respectively.
|
|
|
|
The default value of `150` wasn't stored in the `mana` field, but we are still
|
|
able to retrieve it. That is because the generated accessors return a hard-coded
|
|
default value when it doesn't find the value in the buffer.
|
|
|
|
#### Nested Object Access
|
|
|
|
Accessing nested objects is very similar, with the nested field pointing to
|
|
another object type. Be careful, the field could be `null` if not present.
|
|
|
|
For example, accessing the `pos` `struct`, which is type `Vec3` you would do:
|
|
|
|
=== "C++"
|
|
|
|
```c++
|
|
auto pos = monster->pos();
|
|
auto x = pos->x();
|
|
auto y = pos->y();
|
|
auto z = pos->z();
|
|
```
|
|
|
|
=== "C"
|
|
|
|
```c
|
|
ns(Vec3_struct_t) pos = ns(Monster_pos(monster));
|
|
float x = ns(Vec3_x(pos));
|
|
float y = ns(Vec3_y(pos));
|
|
float z = ns(Vec3_z(pos));
|
|
```
|
|
|
|
=== "C#"
|
|
|
|
```c#
|
|
var pos = monster.Pos.Value;
|
|
var x = pos.X;
|
|
var y = pos.Y;
|
|
var z = pos.Z;
|
|
```
|
|
|
|
=== "Dart"
|
|
|
|
```dart
|
|
myGame.Vec3 pos = monster.pos;
|
|
double x = pos.x;
|
|
double y = pos.y;
|
|
double z = pos.z;
|
|
```
|
|
|
|
=== "Go"
|
|
|
|
```go
|
|
pos := monster.Pos(nil)
|
|
x := pos.X()
|
|
y := pos.Y()
|
|
z := pos.Z()
|
|
|
|
// Note: Whenever you access a new object, like in `Pos()`, a new temporary
|
|
// accessor object gets created. If your code is very performance sensitive,
|
|
// you can pass in a pointer to an existing `Vec3` instead of `nil`. This
|
|
// allows you to reuse it across many calls to reduce the amount of object
|
|
// allocation/garbage collection.
|
|
```
|
|
|
|
=== "Java"
|
|
|
|
```java
|
|
Vec3 pos = monster.pos();
|
|
float x = pos.x();
|
|
float y = pos.y();
|
|
float z = pos.z();
|
|
```
|
|
|
|
=== "JavaScript"
|
|
|
|
```javascript
|
|
var pos = monster.pos();
|
|
var x = pos.x();
|
|
var y = pos.y();
|
|
var z = pos.z();
|
|
```
|
|
|
|
=== "Kotlin"
|
|
|
|
```kotlin
|
|
val pos = monster.pos!!
|
|
val x = pos.x
|
|
val y = pos.y
|
|
val z = pos.z
|
|
```
|
|
|
|
=== "Lobster"
|
|
|
|
```lobster
|
|
let pos = monster.pos
|
|
let x = pos.x
|
|
let y = pos.y
|
|
let z = pos.z
|
|
```
|
|
|
|
=== "Lua"
|
|
|
|
```lua
|
|
local pos = mon:Pos()
|
|
local x = pos:X()
|
|
local y = pos:Y()
|
|
local z = pos:Z()
|
|
```
|
|
|
|
=== "PHP"
|
|
|
|
```php
|
|
$pos = $monster->getPos();
|
|
$x = $pos->getX();
|
|
$y = $pos->getY();
|
|
$z = $pos->getZ();
|
|
```
|
|
|
|
=== "Python"
|
|
|
|
```py
|
|
pos = monster.Pos()
|
|
x = pos.X()
|
|
y = pos.Y()
|
|
z = pos.Z()
|
|
```
|
|
|
|
=== "Rust"
|
|
|
|
```rust
|
|
let pos = monster.pos().unwrap();
|
|
let x = pos.x();
|
|
let y = pos.y();
|
|
let z = pos.z();
|
|
```
|
|
|
|
=== "Swift"
|
|
|
|
```swift
|
|
let pos = monster.pos
|
|
let x = pos.x
|
|
let y = pos.y
|
|
let z = pos.z
|
|
```
|
|
|
|
=== "TypeScript"
|
|
|
|
```ts
|
|
let pos = monster.pos();
|
|
let x = pos.x();
|
|
let y = pos.y();
|
|
let z = pos.z();
|
|
```
|
|
|
|
|
|
Where `x`, `y`, and `z` will contain `1.0`, `2.0`, and `3.0` respectively.
|
|
|
|
### Vector Access
|
|
|
|
Similarly, we can access elements of the `inventory` `vector` by indexing it.
|
|
You can also iterate over the length of the vector.
|
|
|
|
=== "C++"
|
|
|
|
```c++
|
|
flatbuffers::Vector<unsigned char> inv = monster->inventory();
|
|
auto inv_len = inv->size();
|
|
auto third_item = inv->Get(2);
|
|
```
|
|
|
|
=== "C"
|
|
|
|
```c
|
|
// If `inv` hasn't been set, it will be null. It is valid get
|
|
// the length of null which will be 0, useful for iteration.
|
|
flatbuffers_uint8_vec_t inv = ns(Monster_inventory(monster));
|
|
size_t inv_len = flatbuffers_uint8_vec_len(inv);
|
|
```
|
|
|
|
=== "C#"
|
|
|
|
```c#
|
|
int invLength = monster.InventoryLength;
|
|
var thirdItem = monster.Inventory(2);
|
|
```
|
|
|
|
=== "Dart"
|
|
|
|
```dart
|
|
int invLength = monster.inventory.length;
|
|
var thirdItem = monster.inventory[2];
|
|
```
|
|
|
|
=== "Go"
|
|
|
|
```go
|
|
invLength := monster.InventoryLength()
|
|
thirdItem := monster.Inventory(2)
|
|
```
|
|
|
|
=== "Java"
|
|
|
|
```java
|
|
int invLength = monster.inventoryLength();
|
|
byte thirdItem = monster.inventory(2);
|
|
```
|
|
|
|
=== "JavaScript"
|
|
|
|
```javascript
|
|
var invLength = monster.inventoryLength();
|
|
var thirdItem = monster.inventory(2);
|
|
```
|
|
|
|
=== "Kotlin"
|
|
|
|
```kotlin
|
|
val invLength = monster.inventoryLength
|
|
val thirdItem = monster.inventory(2)!!
|
|
```
|
|
|
|
=== "Lobster"
|
|
|
|
```lobster
|
|
let inv_len = monster.inventory_length
|
|
let third_item = monster.inventory(2)
|
|
```
|
|
|
|
=== "Lua"
|
|
|
|
```lua
|
|
local invLength = mon:InventoryLength()
|
|
local thirdItem = mon:Inventory(3) -- Lua is 1-based
|
|
```
|
|
|
|
=== "PHP"
|
|
|
|
```php
|
|
$inv_len = $monster->getInventoryLength();
|
|
$third_item = $monster->getInventory(2);
|
|
```
|
|
|
|
=== "Python"
|
|
|
|
```py
|
|
inv_len = monster.InventoryLength()
|
|
third_item = monster.Inventory(2)
|
|
```
|
|
|
|
=== "Rust"
|
|
|
|
```rust
|
|
// Get and test an element from the `inventory` FlatBuffer's `vector`.
|
|
let inv = monster.inventory().unwrap();
|
|
|
|
// Note that this vector is returned as a slice, because direct access for
|
|
// this type, a `u8` vector, is safe on all platforms:
|
|
let third_item = inv[2];
|
|
```
|
|
|
|
=== "Swift"
|
|
|
|
```swift
|
|
// Get a the count of objects in the vector
|
|
let count = monster.inventoryCount
|
|
|
|
// get item at index 4
|
|
let object = monster.inventory(at: 4)
|
|
|
|
// or you can fetch the entire array
|
|
let inv = monster.inventory
|
|
// inv[4] should equal object
|
|
```
|
|
|
|
=== "TypeScript"
|
|
|
|
```ts
|
|
let invLength = monster.inventoryLength();
|
|
let thirdItem = monster.inventory(2);
|
|
```
|
|
|
|
|
|
For vectors of tables, you can access the elements like any other vector, except
|
|
you need to handle the result as a FlatBuffer table. Here we iterate over the
|
|
`weapons` vector that is houses `Weapon` `tables`.
|
|
|
|
=== "C++"
|
|
|
|
```c++
|
|
flatbuffers::Vector<Weapon> weapons = monster->weapons();
|
|
auto weapon_len = weapons->size();
|
|
auto second_weapon_name = weapons->Get(1)->name()->str();
|
|
auto second_weapon_damage = weapons->Get(1)->damage()
|
|
```
|
|
|
|
=== "C"
|
|
|
|
```c
|
|
ns(Weapon_vec_t) weapons = ns(Monster_weapons(monster));
|
|
size_t weapons_len = ns(Weapon_vec_len(weapons));
|
|
// We can use `const char *` instead of `flatbuffers_string_t`.
|
|
const char *second_weapon_name =
|
|
ns(Weapon_name(ns(Weapon_vec_at(weapons, 1))));
|
|
uint16_t second_weapon_damage =
|
|
ns(Weapon_damage(ns(Weapon_vec_at(weapons, 1))));
|
|
```
|
|
|
|
=== "C#"
|
|
|
|
```c#
|
|
int weaponsLength = monster.WeaponsLength;
|
|
var secondWeaponName = monster.Weapons(1).Name;
|
|
var secondWeaponDamage = monster.Weapons(1).Damage;
|
|
```
|
|
|
|
=== "Dart"
|
|
|
|
```dart
|
|
int weaponsLength = monster.weapons.length;
|
|
var secondWeaponName = monster.weapons[1].name;
|
|
var secondWeaponDamage = monster.Weapons[1].damage;
|
|
```
|
|
|
|
=== "Go"
|
|
|
|
```go
|
|
weaponLength := monster.WeaponsLength()
|
|
// We need a `sample.Weapon` to pass into `monster.Weapons()`
|
|
// to capture the output of the function.k
|
|
weapon := new(sample.Weapon)
|
|
if monster.Weapons(weapon, 1) {
|
|
secondWeaponName := weapon.Name()
|
|
secondWeaponDamage := weapon.Damage()
|
|
}
|
|
```
|
|
|
|
=== "Java"
|
|
|
|
```java
|
|
int weaponsLength = monster.weaponsLength();
|
|
String secondWeaponName = monster.weapons(1).name();
|
|
short secondWeaponDamage = monster.weapons(1).damage();
|
|
```
|
|
|
|
=== "JavaScript"
|
|
|
|
```javascript
|
|
var weaponsLength = monster.weaponsLength();
|
|
var secondWeaponName = monster.weapons(1).name();
|
|
var secondWeaponDamage = monster.weapons(1).damage();
|
|
```
|
|
|
|
=== "Kotlin"
|
|
|
|
```kotlin
|
|
val weaponsLength = monster.weaponsLength
|
|
val secondWeaponName = monster.weapons(1)!!.name
|
|
val secondWeaponDamage = monster.weapons(1)!!.damage
|
|
```
|
|
|
|
=== "Lobster"
|
|
|
|
```lobster
|
|
let weapons_length = monster.weapons_length
|
|
let second_weapon_name = monster.weapons(1).name
|
|
let second_weapon_damage = monster.weapons(1).damage
|
|
```
|
|
|
|
=== "Lua"
|
|
|
|
```lua
|
|
local weaponsLength = mon:WeaponsLength()
|
|
local secondWeaponName = mon:Weapon(2):Name()
|
|
local secondWeaponDamage = mon:Weapon(2):Damage()
|
|
```
|
|
|
|
=== "PHP"
|
|
|
|
```php
|
|
$weapons_len = $monster->getWeaponsLength();
|
|
$second_weapon_name = $monster->getWeapons(1)->getName();
|
|
$second_weapon_damage = $monster->getWeapons(1)->getDamage();
|
|
```
|
|
|
|
=== "Python"
|
|
|
|
```py
|
|
weapons_length = monster.WeaponsLength()
|
|
second_weapon_name = monster.Weapons(1).Name()
|
|
second_weapon_damage = monster.Weapons(1).Damage()
|
|
```
|
|
|
|
=== "Rust"
|
|
|
|
```rust
|
|
// Get and test the `weapons` FlatBuffers's `vector`.
|
|
let weps = monster.weapons().unwrap();
|
|
let weps_len = weps.len();
|
|
|
|
let wep2 = weps.get(1);
|
|
let second_weapon_name = wep2.name();
|
|
let second_weapon_damage = wep2.damage();
|
|
```
|
|
|
|
=== "Swift"
|
|
|
|
```swift
|
|
// Get the count of weapon objects
|
|
let wepsCount = monster.weaponsCount
|
|
|
|
let weapon2 = monster.weapons(at: 1)
|
|
let weaponName = weapon2.name
|
|
let weaponDmg = weapon2.damage
|
|
```
|
|
|
|
=== "TypeScript"
|
|
|
|
```ts
|
|
let weaponsLength = monster.weaponsLength();
|
|
let secondWeaponName = monster.weapons(1).name();
|
|
let secondWeaponDamage = monster.weapons(1).damage();
|
|
```
|
|
|
|
|
|
### Union Access
|
|
|
|
Lastly , we can access our `equipped` `union` field. Just like when we created
|
|
the union, we need to get both parts of the union: the type and the data.
|
|
|
|
We can access the type to dynamically cast the data as needed (since the union
|
|
only stores a FlatBuffer `table`).
|
|
|
|
=== "C++"
|
|
|
|
```c++
|
|
auto union_type = monster.equipped_type();
|
|
|
|
if (union_type == Equipment_Weapon) {
|
|
// Requires `static_cast` to type `const Weapon*`.
|
|
auto weapon = static_cast<const Weapon*>(monster->equipped());
|
|
|
|
auto weapon_name = weapon->name()->str(); // "Axe"
|
|
auto weapon_damage = weapon->damage(); // 5
|
|
}
|
|
```
|
|
|
|
=== "C"
|
|
|
|
```c
|
|
// Access union type field.
|
|
if (ns(Monster_equipped_type(monster)) == ns(Equipment_Weapon)) {
|
|
// Cast to appropriate type:
|
|
// C allows for silent void pointer assignment, so we need no
|
|
// explicit cast.
|
|
ns(Weapon_table_t) weapon = ns(Monster_equipped(monster));
|
|
const char *weapon_name = ns(Weapon_name(weapon)); // "Axe"
|
|
uint16_t weapon_damage = ns(Weapon_damage(weapon)); // 5
|
|
}
|
|
```
|
|
|
|
=== "C#"
|
|
|
|
```c#
|
|
var unionType = monster.EquippedType;
|
|
|
|
if (unionType == Equipment.Weapon) {
|
|
var weapon = monster.Equipped<Weapon>().Value;
|
|
|
|
var weaponName = weapon.Name; // "Axe"
|
|
var weaponDamage = weapon.Damage; // 5
|
|
}
|
|
```
|
|
|
|
=== "Dart"
|
|
|
|
```dart
|
|
var unionType = monster.equippedType.value;
|
|
|
|
if (unionType == myGame.EquipmentTypeId.Weapon.value) {
|
|
myGame.Weapon weapon = mon.equipped as myGame.Weapon;
|
|
|
|
var weaponName = weapon.name; // "Axe"
|
|
var weaponDamage = weapon.damage; // 5
|
|
}
|
|
```
|
|
|
|
=== "Go"
|
|
|
|
```go
|
|
// We need a `flatbuffers.Table` to capture the output of the
|
|
// `monster.Equipped()` function.
|
|
unionTable := new(flatbuffers.Table)
|
|
|
|
if monster.Equipped(unionTable) {
|
|
unionType := monster.EquippedType()
|
|
|
|
if unionType == sample.EquipmentWeapon {
|
|
// Create a `sample.Weapon` object that can be initialized with the
|
|
// contents of the `flatbuffers.Table` (`unionTable`), which was
|
|
// populated by `monster.Equipped()`.
|
|
unionWeapon = new(sample.Weapon)
|
|
unionWeapon.Init(unionTable.Bytes, unionTable.Pos)
|
|
|
|
weaponName = unionWeapon.Name()
|
|
weaponDamage = unionWeapon.Damage()
|
|
}
|
|
}
|
|
```
|
|
|
|
=== "Java"
|
|
|
|
```java
|
|
int unionType = monster.EquippedType();
|
|
|
|
if (unionType == Equipment.Weapon) {
|
|
// Requires an explicit cast to `Weapon`.
|
|
Weapon weapon = (Weapon)monster.equipped(new Weapon());
|
|
|
|
String weaponName = weapon.name(); // "Axe"
|
|
short weaponDamage = weapon.damage(); // 5
|
|
}
|
|
```
|
|
|
|
=== "JavaScript"
|
|
|
|
```javascript
|
|
var unionType = monster.equippedType();
|
|
|
|
if (unionType == MyGame.Sample.Equipment.Weapon) {
|
|
// 'Axe'
|
|
var weaponName = monster.equipped(new MyGame.Sample.Weapon()).name();
|
|
// 5
|
|
var weaponDamage =
|
|
monster.equipped(new MyGame.Sample.Weapon()).damage();
|
|
}
|
|
```
|
|
|
|
=== "Kotlin"
|
|
|
|
```kotlin
|
|
val unionType = monster.EquippedType
|
|
|
|
if (unionType == Equipment.Weapon) {
|
|
// Requires an explicit cast to `Weapon`.
|
|
val weapon = monster.equipped(Weapon()) as Weapon
|
|
|
|
val weaponName = weapon.name // "Axe"
|
|
val weaponDamage = weapon.damage // 5
|
|
}
|
|
```
|
|
|
|
=== "Lobster"
|
|
|
|
```lobster
|
|
union_type = monster.equipped_type
|
|
|
|
if union_type == MyGame_Sample_Equipment_Weapon:
|
|
// `monster.equipped_as_Weapon` returns a FlatBuffer handle much like
|
|
// normal table fields, but this is only valid to call if we already
|
|
// know it is the correct type.
|
|
let union_weapon = monster.equipped_as_Weapon
|
|
|
|
let weapon_name = union_weapon.name // "Axe"
|
|
let weapon_damage = union_weapon.damage // 5
|
|
```
|
|
|
|
=== "Lua"
|
|
|
|
```lua
|
|
local unionType = mon:EquippedType()
|
|
|
|
if unionType == equipment.Weapon then
|
|
local unionWeapon = weapon.New()
|
|
unionWeapon:Init(mon:Equipped().bytes, mon:Equipped().pos)
|
|
|
|
local weaponName = unionWeapon:Name() -- 'Axe'
|
|
local weaponDamage = unionWeapon:Damage() -- 5
|
|
end
|
|
```
|
|
|
|
=== "PHP"
|
|
|
|
```php
|
|
$union_type = $monster->getEquippedType();
|
|
|
|
if ($union_type == \MyGame\Sample\Equipment::Weapon) {
|
|
// "Axe"
|
|
$weapon_name =
|
|
$monster->getEquipped(new \MyGame\Sample\Weapon())->getName();
|
|
// 5
|
|
$weapon_damage =
|
|
$monster->getEquipped(new \MyGame\Sample\Weapon())->getDamage();
|
|
}
|
|
```
|
|
|
|
=== "Python"
|
|
|
|
```py
|
|
union_type = monster.EquippedType()
|
|
|
|
if union_type == MyGame.Sample.Equipment.Equipment().Weapon:
|
|
# `monster.Equipped()` returns a `flatbuffers.Table`, which can be used
|
|
# to initialize a `MyGame.Sample.Weapon.Weapon()`.
|
|
union_weapon = MyGame.Sample.Weapon.Weapon()
|
|
union_weapon.Init(monster.Equipped().Bytes, monster.Equipped().Pos)
|
|
|
|
weapon_name = union_weapon.Name() // 'Axe'
|
|
weapon_damage = union_weapon.Damage() // 5
|
|
```
|
|
|
|
=== "Rust"
|
|
|
|
```rust
|
|
// Get and test the `Equipment` union (`equipped` field).
|
|
// `equipped_as_weapon` returns a FlatBuffer handle much like normal table
|
|
// fields, but this will return `None` if the union is not actually of that
|
|
// type.
|
|
if monster.equipped_type() == Equipment::Weapon {
|
|
let equipped = monster.equipped_as_weapon().unwrap();
|
|
let weapon_name = equipped.name();
|
|
let weapon_damage = equipped.damage();
|
|
```
|
|
|
|
=== "Swift"
|
|
|
|
```swift
|
|
// Get and check if the monster has an equipped item
|
|
if monster.equippedType == .weapon {
|
|
let _weapon = monster.equipped(type: Weapon.self)
|
|
let name = _weapon.name // should return "Axe"
|
|
let dmg = _weapon.damage // should return 5
|
|
}
|
|
```
|
|
|
|
=== "TypeScript"
|
|
|
|
```ts
|
|
let unionType = monster.equippedType();
|
|
|
|
if (unionType == MyGame.Sample.Equipment.Weapon) {
|
|
// 'Axe'
|
|
let weaponName = monster.equipped(new MyGame.Sample.Weapon()).name();
|
|
// 5
|
|
let weaponDamage = monster.equipped(new MyGame.Sample.Weapon()).damage();
|
|
}
|
|
```
|