mirror of
https://github.com/google/flatbuffers.git
synced 2026-06-02 04:04:19 +00:00
2186 lines
58 KiB
HTML
2186 lines
58 KiB
HTML
|
|
<!doctype html>
|
|
<html lang="en" class="no-js">
|
|
<head>
|
|
|
|
<meta charset="utf-8">
|
|
<meta name="viewport" content="width=device-width,initial-scale=1">
|
|
|
|
|
|
|
|
<link rel="canonical" href="https://flatbuffers.dev/internals/">
|
|
|
|
|
|
<link rel="prev" href="../white_paper/">
|
|
|
|
|
|
<link rel="next" href="../intermediate_representation/">
|
|
|
|
|
|
|
|
|
|
|
|
<link rel="icon" href="../assets/images/favicon.png">
|
|
<meta name="generator" content="mkdocs-1.6.1, mkdocs-material-9.7.6">
|
|
|
|
|
|
|
|
<title>FlatBuffers Internals - FlatBuffers Docs</title>
|
|
|
|
|
|
|
|
<link rel="stylesheet" href="../assets/stylesheets/main.484c7ddc.min.css">
|
|
|
|
|
|
<link rel="stylesheet" href="../assets/stylesheets/palette.ab4e12ef.min.css">
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
<link rel="preconnect" href="https://fonts.gstatic.com" crossorigin>
|
|
<link rel="stylesheet" href="https://fonts.googleapis.com/css?family=Roboto:300,300i,400,400i,700,700i%7CRoboto+Mono:400,400i,700,700i&display=fallback">
|
|
<style>:root{--md-text-font:"Roboto";--md-code-font:"Roboto Mono"}</style>
|
|
|
|
|
|
|
|
<script>__md_scope=new URL("..",location),__md_hash=e=>[...e].reduce(((e,_)=>(e<<5)-e+_.charCodeAt(0)),0),__md_get=(e,_=localStorage,t=__md_scope)=>JSON.parse(_.getItem(t.pathname+"."+e)),__md_set=(e,_,t=localStorage,a=__md_scope)=>{try{t.setItem(a.pathname+"."+e,JSON.stringify(_))}catch(e){}}</script>
|
|
|
|
|
|
|
|
|
|
|
|
</head>
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
<body dir="ltr" data-md-color-scheme="default" data-md-color-primary="indigo" data-md-color-accent="indigo">
|
|
|
|
|
|
<input class="md-toggle" data-md-toggle="drawer" type="checkbox" id="__drawer" autocomplete="off">
|
|
<input class="md-toggle" data-md-toggle="search" type="checkbox" id="__search" autocomplete="off">
|
|
<label class="md-overlay" for="__drawer"></label>
|
|
<div data-md-component="skip">
|
|
|
|
|
|
<a href="#flatbuffers_internals" class="md-skip">
|
|
Skip to content
|
|
</a>
|
|
|
|
</div>
|
|
<div data-md-component="announce">
|
|
|
|
</div>
|
|
|
|
|
|
|
|
|
|
|
|
|
|
<header class="md-header md-header--shadow" data-md-component="header">
|
|
<nav class="md-header__inner md-grid" aria-label="Header">
|
|
<a href=".." title="FlatBuffers Docs" class="md-header__button md-logo" aria-label="FlatBuffers Docs" data-md-component="logo">
|
|
|
|
<img src="../assets/flatbuffers_logo.svg" alt="logo">
|
|
|
|
</a>
|
|
<label class="md-header__button md-icon" for="__drawer">
|
|
|
|
<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 24 24"><path d="M3 6h18v2H3zm0 5h18v2H3zm0 5h18v2H3z"/></svg>
|
|
</label>
|
|
<div class="md-header__title" data-md-component="header-title">
|
|
<div class="md-header__ellipsis">
|
|
<div class="md-header__topic">
|
|
<span class="md-ellipsis">
|
|
FlatBuffers Docs
|
|
</span>
|
|
</div>
|
|
<div class="md-header__topic" data-md-component="header-topic">
|
|
<span class="md-ellipsis">
|
|
|
|
FlatBuffers Internals
|
|
|
|
</span>
|
|
</div>
|
|
</div>
|
|
</div>
|
|
|
|
|
|
<form class="md-header__option" data-md-component="palette">
|
|
|
|
|
|
|
|
|
|
<input class="md-option" data-md-color-media="" data-md-color-scheme="default" data-md-color-primary="indigo" data-md-color-accent="indigo" aria-label="Switch to dark mode" type="radio" name="__palette" id="__palette_0">
|
|
|
|
<label class="md-header__button md-icon" title="Switch to dark mode" for="__palette_1" hidden>
|
|
<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 24 24"><path d="M12 8a4 4 0 0 0-4 4 4 4 0 0 0 4 4 4 4 0 0 0 4-4 4 4 0 0 0-4-4m0 10a6 6 0 0 1-6-6 6 6 0 0 1 6-6 6 6 0 0 1 6 6 6 6 0 0 1-6 6m8-9.31V4h-4.69L12 .69 8.69 4H4v4.69L.69 12 4 15.31V20h4.69L12 23.31 15.31 20H20v-4.69L23.31 12z"/></svg>
|
|
</label>
|
|
|
|
|
|
|
|
|
|
|
|
<input class="md-option" data-md-color-media="" data-md-color-scheme="slate" data-md-color-primary="indigo" data-md-color-accent="indigo" aria-label="Switch to light mode" type="radio" name="__palette" id="__palette_1">
|
|
|
|
<label class="md-header__button md-icon" title="Switch to light mode" for="__palette_0" hidden>
|
|
<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 24 24"><path d="M12 18c-.89 0-1.74-.2-2.5-.55C11.56 16.5 13 14.42 13 12s-1.44-4.5-3.5-5.45C10.26 6.2 11.11 6 12 6a6 6 0 0 1 6 6 6 6 0 0 1-6 6m8-9.31V4h-4.69L12 .69 8.69 4H4v4.69L.69 12 4 15.31V20h4.69L12 23.31 15.31 20H20v-4.69L23.31 12z"/></svg>
|
|
</label>
|
|
|
|
|
|
</form>
|
|
|
|
|
|
|
|
<script>var palette=__md_get("__palette");if(palette&&palette.color){if("(prefers-color-scheme)"===palette.color.media){var media=matchMedia("(prefers-color-scheme: light)"),input=document.querySelector(media.matches?"[data-md-color-media='(prefers-color-scheme: light)']":"[data-md-color-media='(prefers-color-scheme: dark)']");palette.color.media=input.getAttribute("data-md-color-media"),palette.color.scheme=input.getAttribute("data-md-color-scheme"),palette.color.primary=input.getAttribute("data-md-color-primary"),palette.color.accent=input.getAttribute("data-md-color-accent")}for(var[key,value]of Object.entries(palette.color))document.body.setAttribute("data-md-color-"+key,value)}</script>
|
|
|
|
|
|
|
|
|
|
<div class="md-header__source">
|
|
<a href="https://github.com/google/flatbuffers" title="Go to repository" class="md-source" data-md-component="source">
|
|
<div class="md-source__icon md-icon">
|
|
|
|
<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 512 512"><!--! Font Awesome Free 7.1.0 by @fontawesome - https://fontawesome.com License - https://fontawesome.com/license/free (Icons: CC BY 4.0, Fonts: SIL OFL 1.1, Code: MIT License) Copyright 2025 Fonticons, Inc.--><path d="M173.9 397.4c0 2-2.3 3.6-5.2 3.6-3.3.3-5.6-1.3-5.6-3.6 0-2 2.3-3.6 5.2-3.6 3-.3 5.6 1.3 5.6 3.6m-31.1-4.5c-.7 2 1.3 4.3 4.3 4.9 2.6 1 5.6 0 6.2-2s-1.3-4.3-4.3-5.2c-2.6-.7-5.5.3-6.2 2.3m44.2-1.7c-2.9.7-4.9 2.6-4.6 4.9.3 2 2.9 3.3 5.9 2.6 2.9-.7 4.9-2.6 4.6-4.6-.3-1.9-3-3.2-5.9-2.9M252.8 8C114.1 8 8 113.3 8 252c0 110.9 69.8 205.8 169.5 239.2 12.8 2.3 17.3-5.6 17.3-12.1 0-6.2-.3-40.4-.3-61.4 0 0-70 15-84.7-29.8 0 0-11.4-29.1-27.8-36.6 0 0-22.9-15.7 1.6-15.4 0 0 24.9 2 38.6 25.8 21.9 38.6 58.6 27.5 72.9 20.9 2.3-16 8.8-27.1 16-33.7-55.9-6.2-112.3-14.3-112.3-110.5 0-27.5 7.6-41.3 23.6-58.9-2.6-6.5-11.1-33.3 2.6-67.9 20.9-6.5 69 27 69 27 20-5.6 41.5-8.5 62.8-8.5s42.8 2.9 62.8 8.5c0 0 48.1-33.6 69-27 13.7 34.7 5.2 61.4 2.6 67.9 16 17.7 25.8 31.5 25.8 58.9 0 96.5-58.9 104.2-114.8 110.5 9.2 7.9 17 22.9 17 46.4 0 33.7-.3 75.4-.3 83.6 0 6.5 4.6 14.4 17.3 12.1C436.2 457.8 504 362.9 504 252 504 113.3 391.5 8 252.8 8M105.2 352.9c-1.3 1-1 3.3.7 5.2 1.6 1.6 3.9 2.3 5.2 1 1.3-1 1-3.3-.7-5.2-1.6-1.6-3.9-2.3-5.2-1m-10.8-8.1c-.7 1.3.3 2.9 2.3 3.9 1.6 1 3.6.7 4.3-.7.7-1.3-.3-2.9-2.3-3.9-2-.6-3.6-.3-4.3.7m32.4 35.6c-1.6 1.3-1 4.3 1.3 6.2 2.3 2.3 5.2 2.6 6.5 1 1.3-1.3.7-4.3-1.3-6.2-2.2-2.3-5.2-2.6-6.5-1m-11.4-14.7c-1.6 1-1.6 3.6 0 5.9s4.3 3.3 5.6 2.3c1.6-1.3 1.6-3.9 0-6.2-1.4-2.3-4-3.3-5.6-2"/></svg>
|
|
</div>
|
|
<div class="md-source__repository">
|
|
google/FlatBuffers
|
|
</div>
|
|
</a>
|
|
</div>
|
|
|
|
</nav>
|
|
|
|
</header>
|
|
|
|
<div class="md-container" data-md-component="container">
|
|
|
|
|
|
|
|
|
|
|
|
|
|
<main class="md-main" data-md-component="main">
|
|
<div class="md-main__inner md-grid">
|
|
|
|
|
|
|
|
<div class="md-sidebar md-sidebar--primary" data-md-component="sidebar" data-md-type="navigation" >
|
|
<div class="md-sidebar__scrollwrap">
|
|
<div class="md-sidebar__inner">
|
|
|
|
|
|
|
|
|
|
<nav class="md-nav md-nav--primary" aria-label="Navigation" data-md-level="0">
|
|
<label class="md-nav__title" for="__drawer">
|
|
<a href=".." title="FlatBuffers Docs" class="md-nav__button md-logo" aria-label="FlatBuffers Docs" data-md-component="logo">
|
|
|
|
<img src="../assets/flatbuffers_logo.svg" alt="logo">
|
|
|
|
</a>
|
|
FlatBuffers Docs
|
|
</label>
|
|
|
|
<div class="md-nav__source">
|
|
<a href="https://github.com/google/flatbuffers" title="Go to repository" class="md-source" data-md-component="source">
|
|
<div class="md-source__icon md-icon">
|
|
|
|
<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 512 512"><!--! Font Awesome Free 7.1.0 by @fontawesome - https://fontawesome.com License - https://fontawesome.com/license/free (Icons: CC BY 4.0, Fonts: SIL OFL 1.1, Code: MIT License) Copyright 2025 Fonticons, Inc.--><path d="M173.9 397.4c0 2-2.3 3.6-5.2 3.6-3.3.3-5.6-1.3-5.6-3.6 0-2 2.3-3.6 5.2-3.6 3-.3 5.6 1.3 5.6 3.6m-31.1-4.5c-.7 2 1.3 4.3 4.3 4.9 2.6 1 5.6 0 6.2-2s-1.3-4.3-4.3-5.2c-2.6-.7-5.5.3-6.2 2.3m44.2-1.7c-2.9.7-4.9 2.6-4.6 4.9.3 2 2.9 3.3 5.9 2.6 2.9-.7 4.9-2.6 4.6-4.6-.3-1.9-3-3.2-5.9-2.9M252.8 8C114.1 8 8 113.3 8 252c0 110.9 69.8 205.8 169.5 239.2 12.8 2.3 17.3-5.6 17.3-12.1 0-6.2-.3-40.4-.3-61.4 0 0-70 15-84.7-29.8 0 0-11.4-29.1-27.8-36.6 0 0-22.9-15.7 1.6-15.4 0 0 24.9 2 38.6 25.8 21.9 38.6 58.6 27.5 72.9 20.9 2.3-16 8.8-27.1 16-33.7-55.9-6.2-112.3-14.3-112.3-110.5 0-27.5 7.6-41.3 23.6-58.9-2.6-6.5-11.1-33.3 2.6-67.9 20.9-6.5 69 27 69 27 20-5.6 41.5-8.5 62.8-8.5s42.8 2.9 62.8 8.5c0 0 48.1-33.6 69-27 13.7 34.7 5.2 61.4 2.6 67.9 16 17.7 25.8 31.5 25.8 58.9 0 96.5-58.9 104.2-114.8 110.5 9.2 7.9 17 22.9 17 46.4 0 33.7-.3 75.4-.3 83.6 0 6.5 4.6 14.4 17.3 12.1C436.2 457.8 504 362.9 504 252 504 113.3 391.5 8 252.8 8M105.2 352.9c-1.3 1-1 3.3.7 5.2 1.6 1.6 3.9 2.3 5.2 1 1.3-1 1-3.3-.7-5.2-1.6-1.6-3.9-2.3-5.2-1m-10.8-8.1c-.7 1.3.3 2.9 2.3 3.9 1.6 1 3.6.7 4.3-.7.7-1.3-.3-2.9-2.3-3.9-2-.6-3.6-.3-4.3.7m32.4 35.6c-1.6 1.3-1 4.3 1.3 6.2 2.3 2.3 5.2 2.6 6.5 1 1.3-1.3.7-4.3-1.3-6.2-2.2-2.3-5.2-2.6-6.5-1m-11.4-14.7c-1.6 1-1.6 3.6 0 5.9s4.3 3.3 5.6 2.3c1.6-1.3 1.6-3.9 0-6.2-1.4-2.3-4-3.3-5.6-2"/></svg>
|
|
</div>
|
|
<div class="md-source__repository">
|
|
google/FlatBuffers
|
|
</div>
|
|
</a>
|
|
</div>
|
|
|
|
<ul class="md-nav__list" data-md-scrollfix>
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
<li class="md-nav__item">
|
|
<a href=".." class="md-nav__link">
|
|
|
|
|
|
|
|
<span class="md-ellipsis">
|
|
|
|
|
|
Overview
|
|
|
|
|
|
|
|
</span>
|
|
|
|
|
|
|
|
</a>
|
|
</li>
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
<li class="md-nav__item">
|
|
<a href="../quick_start/" class="md-nav__link">
|
|
|
|
|
|
|
|
<span class="md-ellipsis">
|
|
|
|
|
|
Quick Start
|
|
|
|
|
|
|
|
</span>
|
|
|
|
|
|
|
|
</a>
|
|
</li>
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
<li class="md-nav__item">
|
|
<a href="../tutorial/" class="md-nav__link">
|
|
|
|
|
|
|
|
<span class="md-ellipsis">
|
|
|
|
|
|
Tutorial
|
|
|
|
|
|
|
|
</span>
|
|
|
|
|
|
|
|
</a>
|
|
</li>
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
<li class="md-nav__item md-nav__item--nested">
|
|
|
|
|
|
|
|
|
|
|
|
<input class="md-nav__toggle md-toggle md-toggle--indeterminate" type="checkbox" id="__nav_4" >
|
|
|
|
|
|
<label class="md-nav__link" for="__nav_4" id="__nav_4_label" tabindex="0">
|
|
|
|
|
|
|
|
<span class="md-ellipsis">
|
|
|
|
|
|
Compiler (flatc)
|
|
|
|
|
|
|
|
</span>
|
|
|
|
|
|
|
|
<span class="md-nav__icon md-icon"></span>
|
|
</label>
|
|
|
|
<nav class="md-nav" data-md-level="1" aria-labelledby="__nav_4_label" aria-expanded="false">
|
|
<label class="md-nav__title" for="__nav_4">
|
|
<span class="md-nav__icon md-icon"></span>
|
|
|
|
|
|
Compiler (flatc)
|
|
|
|
|
|
</label>
|
|
<ul class="md-nav__list" data-md-scrollfix>
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
<li class="md-nav__item">
|
|
<a href="../building/" class="md-nav__link">
|
|
|
|
|
|
|
|
<span class="md-ellipsis">
|
|
|
|
|
|
Building
|
|
|
|
|
|
|
|
</span>
|
|
|
|
|
|
|
|
</a>
|
|
</li>
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
<li class="md-nav__item">
|
|
<a href="../flatc/" class="md-nav__link">
|
|
|
|
|
|
|
|
<span class="md-ellipsis">
|
|
|
|
|
|
Using
|
|
|
|
|
|
|
|
</span>
|
|
|
|
|
|
|
|
</a>
|
|
</li>
|
|
|
|
|
|
|
|
|
|
</ul>
|
|
</nav>
|
|
|
|
</li>
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
<li class="md-nav__item md-nav__item--nested">
|
|
|
|
|
|
|
|
|
|
|
|
<input class="md-nav__toggle md-toggle md-toggle--indeterminate" type="checkbox" id="__nav_5" >
|
|
|
|
|
|
<label class="md-nav__link" for="__nav_5" id="__nav_5_label" tabindex="0">
|
|
|
|
|
|
|
|
<span class="md-ellipsis">
|
|
|
|
|
|
Schema (.fbs)
|
|
|
|
|
|
|
|
</span>
|
|
|
|
|
|
|
|
<span class="md-nav__icon md-icon"></span>
|
|
</label>
|
|
|
|
<nav class="md-nav" data-md-level="1" aria-labelledby="__nav_5_label" aria-expanded="false">
|
|
<label class="md-nav__title" for="__nav_5">
|
|
<span class="md-nav__icon md-icon"></span>
|
|
|
|
|
|
Schema (.fbs)
|
|
|
|
|
|
</label>
|
|
<ul class="md-nav__list" data-md-scrollfix>
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
<li class="md-nav__item">
|
|
<a href="../schema/" class="md-nav__link">
|
|
|
|
|
|
|
|
<span class="md-ellipsis">
|
|
|
|
|
|
Overview
|
|
|
|
|
|
|
|
</span>
|
|
|
|
|
|
|
|
</a>
|
|
</li>
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
<li class="md-nav__item">
|
|
<a href="../evolution/" class="md-nav__link">
|
|
|
|
|
|
|
|
<span class="md-ellipsis">
|
|
|
|
|
|
Evolution
|
|
|
|
|
|
|
|
</span>
|
|
|
|
|
|
|
|
</a>
|
|
</li>
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
<li class="md-nav__item">
|
|
<a href="../grammar/" class="md-nav__link">
|
|
|
|
|
|
|
|
<span class="md-ellipsis">
|
|
|
|
|
|
Grammar
|
|
|
|
|
|
|
|
</span>
|
|
|
|
|
|
|
|
</a>
|
|
</li>
|
|
|
|
|
|
|
|
|
|
</ul>
|
|
</nav>
|
|
|
|
</li>
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
<li class="md-nav__item md-nav__item--nested">
|
|
|
|
|
|
|
|
|
|
|
|
<input class="md-nav__toggle md-toggle md-toggle--indeterminate" type="checkbox" id="__nav_6" >
|
|
|
|
|
|
<label class="md-nav__link" for="__nav_6" id="__nav_6_label" tabindex="0">
|
|
|
|
|
|
|
|
<span class="md-ellipsis">
|
|
|
|
|
|
Language Guides
|
|
|
|
|
|
|
|
</span>
|
|
|
|
|
|
|
|
<span class="md-nav__icon md-icon"></span>
|
|
</label>
|
|
|
|
<nav class="md-nav" data-md-level="1" aria-labelledby="__nav_6_label" aria-expanded="false">
|
|
<label class="md-nav__title" for="__nav_6">
|
|
<span class="md-nav__icon md-icon"></span>
|
|
|
|
|
|
Language Guides
|
|
|
|
|
|
</label>
|
|
<ul class="md-nav__list" data-md-scrollfix>
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
<li class="md-nav__item">
|
|
<a href="../languages/c/" class="md-nav__link">
|
|
|
|
|
|
|
|
<span class="md-ellipsis">
|
|
|
|
|
|
C
|
|
|
|
|
|
|
|
</span>
|
|
|
|
|
|
|
|
</a>
|
|
</li>
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
<li class="md-nav__item">
|
|
<a href="../languages/cpp/" class="md-nav__link">
|
|
|
|
|
|
|
|
<span class="md-ellipsis">
|
|
|
|
|
|
C++
|
|
|
|
|
|
|
|
</span>
|
|
|
|
|
|
|
|
</a>
|
|
</li>
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
<li class="md-nav__item">
|
|
<a href="../languages/c_sharp/" class="md-nav__link">
|
|
|
|
|
|
|
|
<span class="md-ellipsis">
|
|
|
|
|
|
C#
|
|
|
|
|
|
|
|
</span>
|
|
|
|
|
|
|
|
</a>
|
|
</li>
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
<li class="md-nav__item">
|
|
<a href="../languages/dart/" class="md-nav__link">
|
|
|
|
|
|
|
|
<span class="md-ellipsis">
|
|
|
|
|
|
Dart
|
|
|
|
|
|
|
|
</span>
|
|
|
|
|
|
|
|
</a>
|
|
</li>
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
<li class="md-nav__item">
|
|
<a href="../languages/go/" class="md-nav__link">
|
|
|
|
|
|
|
|
<span class="md-ellipsis">
|
|
|
|
|
|
Go
|
|
|
|
|
|
|
|
</span>
|
|
|
|
|
|
|
|
</a>
|
|
</li>
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
<li class="md-nav__item">
|
|
<a href="../languages/java/" class="md-nav__link">
|
|
|
|
|
|
|
|
<span class="md-ellipsis">
|
|
|
|
|
|
Java
|
|
|
|
|
|
|
|
</span>
|
|
|
|
|
|
|
|
</a>
|
|
</li>
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
<li class="md-nav__item">
|
|
<a href="../languages/javascript/" class="md-nav__link">
|
|
|
|
|
|
|
|
<span class="md-ellipsis">
|
|
|
|
|
|
JavaScript
|
|
|
|
|
|
|
|
</span>
|
|
|
|
|
|
|
|
</a>
|
|
</li>
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
<li class="md-nav__item">
|
|
<a href="../languages/kotlin/" class="md-nav__link">
|
|
|
|
|
|
|
|
<span class="md-ellipsis">
|
|
|
|
|
|
Kotlin
|
|
|
|
|
|
|
|
</span>
|
|
|
|
|
|
|
|
</a>
|
|
</li>
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
<li class="md-nav__item">
|
|
<a href="../languages/lobster/" class="md-nav__link">
|
|
|
|
|
|
|
|
<span class="md-ellipsis">
|
|
|
|
|
|
Lobster
|
|
|
|
|
|
|
|
</span>
|
|
|
|
|
|
|
|
</a>
|
|
</li>
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
<li class="md-nav__item">
|
|
<a href="../languages/lua/" class="md-nav__link">
|
|
|
|
|
|
|
|
<span class="md-ellipsis">
|
|
|
|
|
|
Lua
|
|
|
|
|
|
|
|
</span>
|
|
|
|
|
|
|
|
</a>
|
|
</li>
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
<li class="md-nav__item">
|
|
<a href="../languages/php/" class="md-nav__link">
|
|
|
|
|
|
|
|
<span class="md-ellipsis">
|
|
|
|
|
|
PHP
|
|
|
|
|
|
|
|
</span>
|
|
|
|
|
|
|
|
</a>
|
|
</li>
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
<li class="md-nav__item">
|
|
<a href="../languages/python/" class="md-nav__link">
|
|
|
|
|
|
|
|
<span class="md-ellipsis">
|
|
|
|
|
|
Python
|
|
|
|
|
|
|
|
</span>
|
|
|
|
|
|
|
|
</a>
|
|
</li>
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
<li class="md-nav__item">
|
|
<a href="../languages/rust/" class="md-nav__link">
|
|
|
|
|
|
|
|
<span class="md-ellipsis">
|
|
|
|
|
|
Rust
|
|
|
|
|
|
|
|
</span>
|
|
|
|
|
|
|
|
</a>
|
|
</li>
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
<li class="md-nav__item">
|
|
<a href="../languages/swift/" class="md-nav__link">
|
|
|
|
|
|
|
|
<span class="md-ellipsis">
|
|
|
|
|
|
Swift
|
|
|
|
|
|
|
|
</span>
|
|
|
|
|
|
|
|
</a>
|
|
</li>
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
<li class="md-nav__item">
|
|
<a href="../languages/typescript/" class="md-nav__link">
|
|
|
|
|
|
|
|
<span class="md-ellipsis">
|
|
|
|
|
|
TypeScript
|
|
|
|
|
|
|
|
</span>
|
|
|
|
|
|
|
|
</a>
|
|
</li>
|
|
|
|
|
|
|
|
|
|
</ul>
|
|
</nav>
|
|
|
|
</li>
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
<li class="md-nav__item">
|
|
<a href="../support/" class="md-nav__link">
|
|
|
|
|
|
|
|
<span class="md-ellipsis">
|
|
|
|
|
|
Supported Configurations
|
|
|
|
|
|
|
|
</span>
|
|
|
|
|
|
|
|
</a>
|
|
</li>
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
<li class="md-nav__item">
|
|
<a href="../white_paper/" class="md-nav__link">
|
|
|
|
|
|
|
|
<span class="md-ellipsis">
|
|
|
|
|
|
White Paper
|
|
|
|
|
|
|
|
</span>
|
|
|
|
|
|
|
|
</a>
|
|
</li>
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
<li class="md-nav__item md-nav__item--active md-nav__item--nested">
|
|
|
|
|
|
|
|
<input class="md-nav__toggle md-toggle " type="checkbox" id="__nav_9" checked>
|
|
|
|
|
|
<label class="md-nav__link" for="__nav_9" id="__nav_9_label" tabindex="0">
|
|
|
|
|
|
|
|
<span class="md-ellipsis">
|
|
|
|
|
|
Advanced
|
|
|
|
|
|
|
|
</span>
|
|
|
|
|
|
|
|
<span class="md-nav__icon md-icon"></span>
|
|
</label>
|
|
|
|
<nav class="md-nav" data-md-level="1" aria-labelledby="__nav_9_label" aria-expanded="true">
|
|
<label class="md-nav__title" for="__nav_9">
|
|
<span class="md-nav__icon md-icon"></span>
|
|
|
|
|
|
Advanced
|
|
|
|
|
|
</label>
|
|
<ul class="md-nav__list" data-md-scrollfix>
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
<li class="md-nav__item md-nav__item--active">
|
|
|
|
<input class="md-nav__toggle md-toggle" type="checkbox" id="__toc">
|
|
|
|
|
|
|
|
|
|
|
|
<label class="md-nav__link md-nav__link--active" for="__toc">
|
|
|
|
|
|
|
|
<span class="md-ellipsis">
|
|
|
|
|
|
FlatBuffers Internals
|
|
|
|
|
|
|
|
</span>
|
|
|
|
|
|
|
|
<span class="md-nav__icon md-icon"></span>
|
|
</label>
|
|
|
|
<a href="./" class="md-nav__link md-nav__link--active">
|
|
|
|
|
|
|
|
<span class="md-ellipsis">
|
|
|
|
|
|
FlatBuffers Internals
|
|
|
|
|
|
|
|
</span>
|
|
|
|
|
|
|
|
</a>
|
|
|
|
|
|
|
|
<nav class="md-nav md-nav--secondary" aria-label="Table of contents">
|
|
|
|
|
|
|
|
|
|
|
|
|
|
<label class="md-nav__title" for="__toc">
|
|
<span class="md-nav__icon md-icon"></span>
|
|
Table of contents
|
|
</label>
|
|
<ul class="md-nav__list" data-md-component="toc" data-md-scrollfix>
|
|
|
|
<li class="md-nav__item">
|
|
<a href="#format-components" class="md-nav__link">
|
|
<span class="md-ellipsis">
|
|
|
|
Format components
|
|
|
|
</span>
|
|
</a>
|
|
|
|
</li>
|
|
|
|
<li class="md-nav__item">
|
|
<a href="#format-identification" class="md-nav__link">
|
|
<span class="md-ellipsis">
|
|
|
|
Format identification
|
|
|
|
</span>
|
|
</a>
|
|
|
|
</li>
|
|
|
|
<li class="md-nav__item">
|
|
<a href="#offsets" class="md-nav__link">
|
|
<span class="md-ellipsis">
|
|
|
|
Offsets
|
|
|
|
</span>
|
|
</a>
|
|
|
|
</li>
|
|
|
|
<li class="md-nav__item">
|
|
<a href="#structs" class="md-nav__link">
|
|
<span class="md-ellipsis">
|
|
|
|
Structs
|
|
|
|
</span>
|
|
</a>
|
|
|
|
</li>
|
|
|
|
<li class="md-nav__item">
|
|
<a href="#tables" class="md-nav__link">
|
|
<span class="md-ellipsis">
|
|
|
|
Tables
|
|
|
|
</span>
|
|
</a>
|
|
|
|
</li>
|
|
|
|
<li class="md-nav__item">
|
|
<a href="#unions" class="md-nav__link">
|
|
<span class="md-ellipsis">
|
|
|
|
Unions
|
|
|
|
</span>
|
|
</a>
|
|
|
|
</li>
|
|
|
|
<li class="md-nav__item">
|
|
<a href="#strings-and-vectors" class="md-nav__link">
|
|
<span class="md-ellipsis">
|
|
|
|
Strings and Vectors
|
|
|
|
</span>
|
|
</a>
|
|
|
|
</li>
|
|
|
|
<li class="md-nav__item">
|
|
<a href="#construction" class="md-nav__link">
|
|
<span class="md-ellipsis">
|
|
|
|
Construction
|
|
|
|
</span>
|
|
</a>
|
|
|
|
</li>
|
|
|
|
<li class="md-nav__item">
|
|
<a href="#code-example" class="md-nav__link">
|
|
<span class="md-ellipsis">
|
|
|
|
Code example
|
|
|
|
</span>
|
|
</a>
|
|
|
|
</li>
|
|
|
|
<li class="md-nav__item">
|
|
<a href="#encoding-example" class="md-nav__link">
|
|
<span class="md-ellipsis">
|
|
|
|
Encoding example.
|
|
|
|
</span>
|
|
</a>
|
|
|
|
</li>
|
|
|
|
<li class="md-nav__item">
|
|
<a href="#additional-reading" class="md-nav__link">
|
|
<span class="md-ellipsis">
|
|
|
|
Additional reading.
|
|
|
|
</span>
|
|
</a>
|
|
|
|
</li>
|
|
|
|
</ul>
|
|
|
|
</nav>
|
|
|
|
</li>
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
<li class="md-nav__item">
|
|
<a href="../intermediate_representation/" class="md-nav__link">
|
|
|
|
|
|
|
|
<span class="md-ellipsis">
|
|
|
|
|
|
Intermediate Representation
|
|
|
|
|
|
|
|
</span>
|
|
|
|
|
|
|
|
</a>
|
|
</li>
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
<li class="md-nav__item">
|
|
<a href="../annotation/" class="md-nav__link">
|
|
|
|
|
|
|
|
<span class="md-ellipsis">
|
|
|
|
|
|
Annotating Buffers (.afb)
|
|
|
|
|
|
|
|
</span>
|
|
|
|
|
|
|
|
</a>
|
|
</li>
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
<li class="md-nav__item">
|
|
<a href="../benchmarks/" class="md-nav__link">
|
|
|
|
|
|
|
|
<span class="md-ellipsis">
|
|
|
|
|
|
Benchmarks
|
|
|
|
|
|
|
|
</span>
|
|
|
|
|
|
|
|
</a>
|
|
</li>
|
|
|
|
|
|
|
|
|
|
</ul>
|
|
</nav>
|
|
|
|
</li>
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
<li class="md-nav__item">
|
|
<a href="../flexbuffers/" class="md-nav__link">
|
|
|
|
|
|
|
|
<span class="md-ellipsis">
|
|
|
|
|
|
FlexBuffers (Schema-less version)
|
|
|
|
|
|
|
|
</span>
|
|
|
|
|
|
|
|
</a>
|
|
</li>
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
<li class="md-nav__item">
|
|
<a href="../contributing/" class="md-nav__link">
|
|
|
|
|
|
|
|
<span class="md-ellipsis">
|
|
|
|
|
|
Contributing
|
|
|
|
|
|
|
|
</span>
|
|
|
|
|
|
|
|
</a>
|
|
</li>
|
|
|
|
|
|
|
|
</ul>
|
|
</nav>
|
|
</div>
|
|
</div>
|
|
</div>
|
|
|
|
|
|
|
|
<div class="md-sidebar md-sidebar--secondary" data-md-component="sidebar" data-md-type="toc" >
|
|
<div class="md-sidebar__scrollwrap">
|
|
<div class="md-sidebar__inner">
|
|
|
|
|
|
<nav class="md-nav md-nav--secondary" aria-label="Table of contents">
|
|
|
|
|
|
|
|
|
|
|
|
|
|
<label class="md-nav__title" for="__toc">
|
|
<span class="md-nav__icon md-icon"></span>
|
|
Table of contents
|
|
</label>
|
|
<ul class="md-nav__list" data-md-component="toc" data-md-scrollfix>
|
|
|
|
<li class="md-nav__item">
|
|
<a href="#format-components" class="md-nav__link">
|
|
<span class="md-ellipsis">
|
|
|
|
Format components
|
|
|
|
</span>
|
|
</a>
|
|
|
|
</li>
|
|
|
|
<li class="md-nav__item">
|
|
<a href="#format-identification" class="md-nav__link">
|
|
<span class="md-ellipsis">
|
|
|
|
Format identification
|
|
|
|
</span>
|
|
</a>
|
|
|
|
</li>
|
|
|
|
<li class="md-nav__item">
|
|
<a href="#offsets" class="md-nav__link">
|
|
<span class="md-ellipsis">
|
|
|
|
Offsets
|
|
|
|
</span>
|
|
</a>
|
|
|
|
</li>
|
|
|
|
<li class="md-nav__item">
|
|
<a href="#structs" class="md-nav__link">
|
|
<span class="md-ellipsis">
|
|
|
|
Structs
|
|
|
|
</span>
|
|
</a>
|
|
|
|
</li>
|
|
|
|
<li class="md-nav__item">
|
|
<a href="#tables" class="md-nav__link">
|
|
<span class="md-ellipsis">
|
|
|
|
Tables
|
|
|
|
</span>
|
|
</a>
|
|
|
|
</li>
|
|
|
|
<li class="md-nav__item">
|
|
<a href="#unions" class="md-nav__link">
|
|
<span class="md-ellipsis">
|
|
|
|
Unions
|
|
|
|
</span>
|
|
</a>
|
|
|
|
</li>
|
|
|
|
<li class="md-nav__item">
|
|
<a href="#strings-and-vectors" class="md-nav__link">
|
|
<span class="md-ellipsis">
|
|
|
|
Strings and Vectors
|
|
|
|
</span>
|
|
</a>
|
|
|
|
</li>
|
|
|
|
<li class="md-nav__item">
|
|
<a href="#construction" class="md-nav__link">
|
|
<span class="md-ellipsis">
|
|
|
|
Construction
|
|
|
|
</span>
|
|
</a>
|
|
|
|
</li>
|
|
|
|
<li class="md-nav__item">
|
|
<a href="#code-example" class="md-nav__link">
|
|
<span class="md-ellipsis">
|
|
|
|
Code example
|
|
|
|
</span>
|
|
</a>
|
|
|
|
</li>
|
|
|
|
<li class="md-nav__item">
|
|
<a href="#encoding-example" class="md-nav__link">
|
|
<span class="md-ellipsis">
|
|
|
|
Encoding example.
|
|
|
|
</span>
|
|
</a>
|
|
|
|
</li>
|
|
|
|
<li class="md-nav__item">
|
|
<a href="#additional-reading" class="md-nav__link">
|
|
<span class="md-ellipsis">
|
|
|
|
Additional reading.
|
|
|
|
</span>
|
|
</a>
|
|
|
|
</li>
|
|
|
|
</ul>
|
|
|
|
</nav>
|
|
</div>
|
|
</div>
|
|
</div>
|
|
|
|
|
|
|
|
<div class="md-content" data-md-component="content">
|
|
|
|
<article class="md-content__inner md-typeset">
|
|
|
|
|
|
|
|
|
|
|
|
<a href="https://github.com/google/flatbuffers/edit/master/docs/source/internals.md" title="Edit this page" class="md-content__button md-icon" rel="edit">
|
|
|
|
<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 24 24"><path d="M10 20H6V4h7v5h5v3.1l2-2V8l-6-6H6c-1.1 0-2 .9-2 2v16c0 1.1.9 2 2 2h4zm10.2-7c.1 0 .3.1.4.2l1.3 1.3c.2.2.2.6 0 .8l-1 1-2.1-2.1 1-1c.1-.1.2-.2.4-.2m0 3.9L14.1 23H12v-2.1l6.1-6.1z"/></svg>
|
|
</a>
|
|
|
|
|
|
|
|
|
|
<h1 id="flatbuffers_internals">FlatBuffer Internals</h1>
|
|
<p>This section is entirely optional for the use of FlatBuffers. In normal
|
|
usage, you should never need the information contained herein. If you're
|
|
interested however, it should give you more of an appreciation of why
|
|
FlatBuffers is both efficient and convenient.</p>
|
|
<h3 id="format-components">Format components</h3>
|
|
<p>A FlatBuffer is a binary file and in-memory format consisting mostly of
|
|
scalars of various sizes, all aligned to their own size. Each scalar is
|
|
also always represented in little-endian format, as this corresponds to
|
|
all commonly used CPUs today. FlatBuffers will also work on big-endian
|
|
machines, but will be slightly slower because of additional
|
|
byte-swap intrinsics.</p>
|
|
<p>It is assumed that the following conditions are met, to ensure
|
|
cross-platform interoperability:
|
|
- The binary <code>IEEE-754</code> format is used for floating-point numbers.
|
|
- The <code>two's complemented</code> representation is used for signed integers.
|
|
- The endianness is the same for floating-point numbers as for integers.</p>
|
|
<p>On purpose, the format leaves a lot of details about where exactly
|
|
things live in memory undefined, e.g. fields in a table can have any
|
|
order, and objects to some extent can be stored in many orders. This is
|
|
because the format doesn't need this information to be efficient, and it
|
|
leaves room for optimization and extension (for example, fields can be
|
|
packed in a way that is most compact). Instead, the format is defined in
|
|
terms of offsets and adjacency only. This may mean two different
|
|
implementations may produce different binaries given the same input
|
|
values, and this is perfectly valid.</p>
|
|
<h3 id="format-identification">Format identification</h3>
|
|
<p>The format also doesn't contain information for format identification
|
|
and versioning, which is also by design. FlatBuffers is a statically typed
|
|
system, meaning the user of a buffer needs to know what kind of buffer
|
|
it is. FlatBuffers can of course be wrapped inside other containers
|
|
where needed, or you can use its union feature to dynamically identify
|
|
multiple possible sub-objects stored. Additionally, it can be used
|
|
together with the schema parser if full reflective capabilities are
|
|
desired.</p>
|
|
<p>Versioning is something that is intrinsically part of the format (the
|
|
optionality / extensibility of fields), so the format itself does not
|
|
need a version number (it's a meta-format, in a sense). We're hoping
|
|
that this format can accommodate all data needed. If format breaking
|
|
changes are ever necessary, it would become a new kind of format rather
|
|
than just a variation.</p>
|
|
<h3 id="offsets">Offsets</h3>
|
|
<p>The most important and generic offset type (see <code>flatbuffers.h</code>) is
|
|
<code>uoffset_t</code>, which is currently always a <code>uint32_t</code>, and is used to
|
|
refer to all tables/unions/strings/vectors (these are never stored
|
|
in-line). 32bit is
|
|
intentional, since we want to keep the format binary compatible between
|
|
32 and 64bit systems, and a 64bit offset would bloat the size for almost
|
|
all uses. A version of this format with 64bit (or 16bit) offsets is easy to set
|
|
when needed. Unsigned means they can only point in one direction, which
|
|
typically is forward (towards a higher memory location). Any backwards
|
|
offsets will be explicitly marked as such.</p>
|
|
<p>The format starts with an <code>uoffset_t</code> to the root table in the buffer.</p>
|
|
<p>We have two kinds of objects, structs and tables.</p>
|
|
<h3 id="structs">Structs</h3>
|
|
<p>These are the simplest, and as mentioned, intended for simple data that
|
|
benefits from being extra efficient and doesn't need versioning /
|
|
extensibility. They are always stored inline in their parent (a struct,
|
|
table, or vector) for maximum compactness. Structs define a consistent
|
|
memory layout where all components are aligned to their size, and
|
|
structs aligned to their largest scalar member. This is done independent
|
|
of the alignment rules of the underlying compiler to guarantee a cross
|
|
platform compatible layout. This layout is then enforced in the generated
|
|
code.</p>
|
|
<h3 id="tables">Tables</h3>
|
|
<p>Unlike structs, these are not stored in inline in their parent, but are
|
|
referred to by offset.</p>
|
|
<p>They start with an <code>soffset_t</code> to a vtable. This is a signed version of
|
|
<code>uoffset_t</code>, since vtables may be stored anywhere relative to the object.
|
|
This offset is subtracted (not added) from the object start to arrive at
|
|
the vtable start. This offset is followed by all the
|
|
fields as aligned scalars (or offsets). Unlike structs, not all fields
|
|
need to be present. There is no set order and layout. A table may contain
|
|
field offsets that point to the same value if the user explicitly
|
|
serializes the same offset twice.</p>
|
|
<p>To be able to access fields regardless of these uncertainties, we go
|
|
through a vtable of offsets. Vtables are shared between any objects that
|
|
happen to have the same vtable values.</p>
|
|
<p>The elements of a vtable are all of type <code>voffset_t</code>, which is
|
|
a <code>uint16_t</code>. The first element is the size of the vtable in bytes,
|
|
including the size element. The second one is the size of the object, in bytes
|
|
(including the vtable offset). This size could be used for streaming, to know
|
|
how many bytes to read to be able to access all <em>inline</em> fields of the object.
|
|
The remaining elements are the N offsets, where N is the amount of fields
|
|
declared in the schema when the code that constructed this buffer was
|
|
compiled (thus, the size of the table is N + 2).</p>
|
|
<p>All accessor functions in the generated code for tables contain the
|
|
offset into this table as a constant. This offset is checked against the
|
|
first field (the number of elements), to protect against newer code
|
|
reading older data. If this offset is out of range, or the vtable entry
|
|
is 0, that means the field is not present in this object, and the
|
|
default value is return. Otherwise, the entry is used as offset to the
|
|
field to be read.</p>
|
|
<h3 id="unions">Unions</h3>
|
|
<p>Unions are encoded as the combination of two fields: an enum representing the
|
|
union choice and the offset to the actual element. FlatBuffers reserves the
|
|
enumeration constant <code>NONE</code> (encoded as 0) to mean that the union field is not
|
|
set.</p>
|
|
<h3 id="strings-and-vectors">Strings and Vectors</h3>
|
|
<p>Strings are simply a vector of bytes, and are always
|
|
null-terminated. Vectors are stored as contiguous aligned scalar
|
|
elements prefixed by a 32bit element count (not including any
|
|
null termination). Neither is stored inline in their parent, but are referred to
|
|
by offset. A vector may consist of more than one offset pointing to the same
|
|
value if the user explicitly serializes the same offset twice.</p>
|
|
<h3 id="construction">Construction</h3>
|
|
<p>The current implementation constructs these buffers backwards (starting
|
|
at the highest memory address of the buffer), since
|
|
that significantly reduces the amount of bookkeeping and simplifies the
|
|
construction API.</p>
|
|
<h3 id="code-example">Code example</h3>
|
|
<p>Here's an example of the code that gets generated for the <code>samples/monster.fbs</code>.
|
|
What follows is the entire file, broken up by comments:</p>
|
|
<div class="highlight"><pre><span></span><code>// automatically generated, do not modify
|
|
|
|
#include "flatbuffers/flatbuffers.h"
|
|
|
|
namespace MyGame {
|
|
namespace Sample {
|
|
</code></pre></div>
|
|
<p>Nested namespace support.</p>
|
|
<div class="highlight"><pre><span></span><code>enum {
|
|
Color_Red = 0,
|
|
Color_Green = 1,
|
|
Color_Blue = 2,
|
|
};
|
|
|
|
inline const char **EnumNamesColor() {
|
|
static const char *names[] = { "Red", "Green", "Blue", nullptr };
|
|
return names;
|
|
}
|
|
|
|
inline const char *EnumNameColor(int e) { return EnumNamesColor()[e]; }
|
|
</code></pre></div>
|
|
<p>Enums and convenient reverse lookup.</p>
|
|
<div class="highlight"><pre><span></span><code>enum {
|
|
Any_NONE = 0,
|
|
Any_Monster = 1,
|
|
};
|
|
|
|
inline const char **EnumNamesAny() {
|
|
static const char *names[] = { "NONE", "Monster", nullptr };
|
|
return names;
|
|
}
|
|
|
|
inline const char *EnumNameAny(int e) { return EnumNamesAny()[e]; }
|
|
</code></pre></div>
|
|
<p>Unions share a lot with enums.</p>
|
|
<div class="highlight"><pre><span></span><code>struct Vec3;
|
|
struct Monster;
|
|
</code></pre></div>
|
|
<p>Predeclare all data types since circular references between types are allowed
|
|
(circular references between object are not, though).</p>
|
|
<div class="highlight"><pre><span></span><code>FLATBUFFERS_MANUALLY_ALIGNED_STRUCT(4) Vec3 {
|
|
private:
|
|
float x_;
|
|
float y_;
|
|
float z_;
|
|
|
|
public:
|
|
Vec3(float x, float y, float z)
|
|
: x_(flatbuffers::EndianScalar(x)), y_(flatbuffers::EndianScalar(y)), z_(flatbuffers::EndianScalar(z)) {}
|
|
|
|
float x() const { return flatbuffers::EndianScalar(x_); }
|
|
float y() const { return flatbuffers::EndianScalar(y_); }
|
|
float z() const { return flatbuffers::EndianScalar(z_); }
|
|
};
|
|
FLATBUFFERS_STRUCT_END(Vec3, 12);
|
|
</code></pre></div>
|
|
<p>These ugly macros do a couple of things: they turn off any padding the compiler
|
|
might normally do, since we add padding manually (though none in this example),
|
|
and they enforce alignment chosen by FlatBuffers. This ensures the layout of
|
|
this struct will look the same regardless of compiler and platform. Note that
|
|
the fields are private: this is because these store little endian scalars
|
|
regardless of platform (since this is part of the serialized data).
|
|
<code>EndianScalar</code> then converts back and forth, which is a no-op on all current
|
|
mobile and desktop platforms, and a single machine instruction on the few
|
|
remaining big endian platforms.</p>
|
|
<div class="highlight"><pre><span></span><code>struct Monster : private flatbuffers::Table {
|
|
const Vec3 *pos() const { return GetStruct<const Vec3 *>(4); }
|
|
int16_t mana() const { return GetField<int16_t>(6, 150); }
|
|
int16_t hp() const { return GetField<int16_t>(8, 100); }
|
|
const flatbuffers::String *name() const { return GetPointer<const flatbuffers::String *>(10); }
|
|
const flatbuffers::Vector<uint8_t> *inventory() const { return GetPointer<const flatbuffers::Vector<uint8_t> *>(14); }
|
|
int8_t color() const { return GetField<int8_t>(16, 2); }
|
|
};
|
|
</code></pre></div>
|
|
<p>Tables are a bit more complicated. A table accessor struct is used to point at
|
|
the serialized data for a table, which always starts with an offset to its
|
|
vtable. It derives from <code>Table</code>, which contains the <code>GetField</code> helper functions.
|
|
GetField takes a vtable offset, and a default value. It will look in the vtable
|
|
at that offset. If the offset is out of bounds (data from an older version) or
|
|
the vtable entry is 0, the field is not present and the default is returned.
|
|
Otherwise, it uses the entry as an offset into the table to locate the field.</p>
|
|
<div class="highlight"><pre><span></span><code>struct MonsterBuilder {
|
|
flatbuffers::FlatBufferBuilder &fbb_;
|
|
flatbuffers::uoffset_t start_;
|
|
void add_pos(const Vec3 *pos) { fbb_.AddStruct(4, pos); }
|
|
void add_mana(int16_t mana) { fbb_.AddElement<int16_t>(6, mana, 150); }
|
|
void add_hp(int16_t hp) { fbb_.AddElement<int16_t>(8, hp, 100); }
|
|
void add_name(flatbuffers::Offset<flatbuffers::String> name) { fbb_.AddOffset(10, name); }
|
|
void add_inventory(flatbuffers::Offset<flatbuffers::Vector<uint8_t>> inventory) { fbb_.AddOffset(14, inventory); }
|
|
void add_color(int8_t color) { fbb_.AddElement<int8_t>(16, color, 2); }
|
|
MonsterBuilder(flatbuffers::FlatBufferBuilder &_fbb) : fbb_(_fbb) { start_ = fbb_.StartTable(); }
|
|
flatbuffers::Offset<Monster> Finish() { return flatbuffers::Offset<Monster>(fbb_.EndTable(start_, 7)); }
|
|
};
|
|
</code></pre></div>
|
|
<p><code>MonsterBuilder</code> is the base helper struct to construct a table using a
|
|
<code>FlatBufferBuilder</code>. You can add the fields in any order, and the <code>Finish</code>
|
|
call will ensure the correct vtable gets generated.</p>
|
|
<div class="highlight"><pre><span></span><code>inline flatbuffers::Offset<Monster> CreateMonster(flatbuffers::FlatBufferBuilder &_fbb,
|
|
const Vec3 *pos, int16_t mana,
|
|
int16_t hp,
|
|
flatbuffers::Offset<flatbuffers::String> name,
|
|
flatbuffers::Offset<flatbuffers::Vector<uint8_t>> inventory,
|
|
int8_t color) {
|
|
MonsterBuilder builder_(_fbb);
|
|
builder_.add_inventory(inventory);
|
|
builder_.add_name(name);
|
|
builder_.add_pos(pos);
|
|
builder_.add_hp(hp);
|
|
builder_.add_mana(mana);
|
|
builder_.add_color(color);
|
|
return builder_.Finish();
|
|
}
|
|
</code></pre></div>
|
|
<p><code>CreateMonster</code> is a convenience function that calls all functions in
|
|
<code>MonsterBuilder</code> above for you. Note that if you pass values which are
|
|
defaults as arguments, it will not actually construct that field, so
|
|
you can probably use this function instead of the builder class in
|
|
almost all cases.</p>
|
|
<div class="highlight"><pre><span></span><code>inline const Monster *GetMonster(const void *buf) { return flatbuffers::GetRoot<Monster>(buf); }
|
|
</code></pre></div>
|
|
<p>This function is only generated for the root table type, to be able to
|
|
start traversing a FlatBuffer from a raw buffer pointer.</p>
|
|
<div class="highlight"><pre><span></span><code>}; // namespace MyGame
|
|
}; // namespace Sample
|
|
</code></pre></div>
|
|
<h3 id="encoding-example">Encoding example.</h3>
|
|
<p>Below is a sample encoding for the following JSON corresponding to the above
|
|
schema:</p>
|
|
<div class="highlight"><pre><span></span><code>{ pos: { x: 1, y: 2, z: 3 }, name: "fred", hp: 50 }
|
|
</code></pre></div>
|
|
<p>Resulting in this binary buffer:</p>
|
|
<div class="highlight"><pre><span></span><code>// Start of the buffer:
|
|
uint32_t 20 // Offset to the root table.
|
|
|
|
// Start of the vtable. Not shared in this example, but could be:
|
|
uint16_t 16 // Size of table, starting from here.
|
|
uint16_t 22 // Size of object inline data.
|
|
uint16_t 4, 0, 20, 16, 0, 0 // Offsets to fields from start of (root) table, 0 for not present.
|
|
|
|
// Start of the root table:
|
|
int32_t 16 // Offset to vtable used (default negative direction)
|
|
float 1, 2, 3 // the Vec3 struct, inline.
|
|
uint32_t 8 // Offset to the name string.
|
|
int16_t 50 // hp field.
|
|
int16_t 0 // Padding for alignment.
|
|
|
|
// Start of name string:
|
|
uint32_t 4 // Length of string.
|
|
int8_t 'f', 'r', 'e', 'd', 0, 0, 0, 0 // Text + 0 termination + padding.
|
|
</code></pre></div>
|
|
<p>Note that this not the only possible encoding, since the writer has some
|
|
flexibility in which of the children of root object to write first (though in
|
|
this case there's only one string), and what order to write the fields in.
|
|
Different orders may also cause different alignments to happen.</p>
|
|
<h3 id="additional-reading">Additional reading.</h3>
|
|
<p>The author of the C language implementation has made a similar
|
|
<a href="https://github.com/dvidelabs/flatcc/blob/master/doc/binary-format.md#flatbuffers-binary-format">document</a>
|
|
that may further help clarify the format.</p>
|
|
<h1 id="flexbuffers">FlexBuffers</h1>
|
|
<p>The <a href="../flexbuffers/">schema-less</a> version of FlatBuffers have their
|
|
own encoding, detailed here.</p>
|
|
<p>It shares many properties mentioned above, in that all data is accessed
|
|
over offsets, all scalars are aligned to their own size, and
|
|
all data is always stored in little endian format.</p>
|
|
<p>One difference is that FlexBuffers are built front to back, so children are
|
|
stored before parents, and the root of the data starts at the last byte.</p>
|
|
<p>Another difference is that scalar data is stored with a variable number of bits
|
|
(8/16/32/64). The current width is always determined by the <em>parent</em>, i.e. if
|
|
the scalar sits in a vector, the vector determines the bit width for all
|
|
elements at once. Selecting the minimum bit width for a particular vector is
|
|
something the encoder does automatically and thus is typically of no concern
|
|
to the user, though being aware of this feature (and not sticking a double in
|
|
the same vector as a bunch of byte sized elements) is helpful for efficiency.</p>
|
|
<p>Unlike FlatBuffers there is only one kind of offset, and that is an unsigned
|
|
integer indicating the number of bytes in a negative direction from the address
|
|
of itself (where the offset is stored).</p>
|
|
<h3 id="vectors">Vectors</h3>
|
|
<p>The representation of the vector is at the core of how FlexBuffers works (since
|
|
maps are really just a combination of 2 vectors), so it is worth starting there.</p>
|
|
<p>As mentioned, a vector is governed by a single bit width (supplied by its
|
|
parent). This includes the size field. For example, a vector that stores the
|
|
integer values <code>1, 2, 3</code> is encoded as follows:</p>
|
|
<div class="highlight"><pre><span></span><code>uint8_t 3, 1, 2, 3, 4, 4, 4
|
|
</code></pre></div>
|
|
<p>The first <code>3</code> is the size field, and is placed before the vector (an offset
|
|
from the parent to this vector points to the first element, not the size
|
|
field, so the size field is effectively at index -1).
|
|
Since this is an untyped vector <code>SL_VECTOR</code>, it is followed by 3 type
|
|
bytes (one per element of the vector), which are always following the vector,
|
|
and are always a uint8_t even if the vector is made up of bigger scalars.</p>
|
|
<p>A vector may include more than one offset pointing to the same value if the
|
|
user explicitly serializes the same offset twice.</p>
|
|
<h3 id="types">Types</h3>
|
|
<p>A type byte is made up of 2 components (see flexbuffers.h for exact values):</p>
|
|
<ul>
|
|
<li>2 lower bits representing the bit-width of the child (8, 16, 32, 64).
|
|
This is only used if the child is accessed over an offset, such as a child
|
|
vector. It is ignored for inline types.</li>
|
|
<li>6 bits representing the actual type (see flexbuffers.h).</li>
|
|
</ul>
|
|
<p>Thus, in this example <code>4</code> means 8 bit child (value 0, unused, since the value is
|
|
in-line), type <code>SL_INT</code> (value 1).</p>
|
|
<h3 id="typed-vectors">Typed Vectors</h3>
|
|
<p>These are like the Vectors above, but omit the type bytes. The type is instead
|
|
determined by the vector type supplied by the parent. Typed vectors are only
|
|
available for a subset of types for which these savings can be significant,
|
|
namely inline signed/unsigned integers (<code>TYPE_VECTOR_INT</code> / <code>TYPE_VECTOR_UINT</code>),
|
|
floats (<code>TYPE_VECTOR_FLOAT</code>), and keys (<code>TYPE_VECTOR_KEY</code>, see below).</p>
|
|
<p>Additionally, for scalars, there are fixed length vectors of sizes 2 / 3 / 4
|
|
that don't store the size (<code>TYPE_VECTOR_INT2</code> etc.), for an additional savings
|
|
in space when storing common vector or color data.</p>
|
|
<h3 id="scalars">Scalars</h3>
|
|
<p>FlexBuffers supports integers (<code>TYPE_INT</code> and <code>TYPE_UINT</code>) and floats
|
|
(<code>TYPE_FLOAT</code>), available in the bit-widths mentioned above. They can be stored
|
|
both inline and over an offset (<code>TYPE_INDIRECT_*</code>).</p>
|
|
<p>The offset version is useful to encode costly 64bit (or even 32bit) quantities
|
|
into vectors / maps of smaller sizes, and to share / repeat a value multiple
|
|
times.</p>
|
|
<h3 id="booleans-and-nulls">Booleans and Nulls</h3>
|
|
<p>Booleans (<code>TYPE_BOOL</code>) and nulls (<code>TYPE_NULL</code>) are encoded as inlined unsigned integers.</p>
|
|
<h3 id="blobs-strings-and-keys">Blobs, Strings and Keys.</h3>
|
|
<p>A blob (<code>TYPE_BLOB</code>) is encoded similar to a vector, with one difference: the
|
|
elements are always <code>uint8_t</code>. The parent bit width only determines the width of
|
|
the size field, allowing blobs to be large without the elements being large.</p>
|
|
<p>Strings (<code>TYPE_STRING</code>) are similar to blobs, except they have an additional 0
|
|
termination byte for convenience, and they MUST be UTF-8 encoded (since an
|
|
accessor in a language that does not support pointers to UTF-8 data may have to
|
|
convert them to a native string type).</p>
|
|
<p>A "Key" (<code>TYPE_KEY</code>) is similar to a string, but doesn't store the size
|
|
field. They're so named because they are used with maps, which don't care
|
|
for the size, and can thus be even more compact. Unlike strings, keys cannot
|
|
contain bytes of value 0 as part of their data (size can only be determined by
|
|
<code>strlen</code>), so while you can use them outside the context of maps if you so
|
|
desire, you're usually better off with strings.</p>
|
|
<h3 id="maps">Maps</h3>
|
|
<p>A map (<code>TYPE_MAP</code>) is like an (untyped) vector, but with 2 prefixes before the
|
|
size field:</p>
|
|
<table>
|
|
<thead>
|
|
<tr>
|
|
<th style="text-align: right;">index</th>
|
|
<th style="text-align: left;">field</th>
|
|
</tr>
|
|
</thead>
|
|
<tbody>
|
|
<tr>
|
|
<td style="text-align: right;">-3</td>
|
|
<td style="text-align: left;">An offset to the keys vector (may be shared between tables).</td>
|
|
</tr>
|
|
<tr>
|
|
<td style="text-align: right;">-2</td>
|
|
<td style="text-align: left;">Byte width of the keys vector.</td>
|
|
</tr>
|
|
<tr>
|
|
<td style="text-align: right;">-1</td>
|
|
<td style="text-align: left;">Size (from here on it is compatible with <code>TYPE_VECTOR</code>)</td>
|
|
</tr>
|
|
<tr>
|
|
<td style="text-align: right;">0</td>
|
|
<td style="text-align: left;">Elements.</td>
|
|
</tr>
|
|
<tr>
|
|
<td style="text-align: right;">Size</td>
|
|
<td style="text-align: left;">Types.</td>
|
|
</tr>
|
|
</tbody>
|
|
</table>
|
|
<p>Since a map is otherwise the same as a vector, it can be iterated like
|
|
a vector (which is probably faster than lookup by key).</p>
|
|
<p>The keys vector is a typed vector of keys. Both the keys and corresponding
|
|
values <em>have</em> to be stored in sorted order (as determined by <code>strcmp</code>), such
|
|
that lookups can be made using binary search.</p>
|
|
<p>The reason the key vector is a separate structure from the value vector is
|
|
such that it can be shared between multiple value vectors, and also to
|
|
allow it to be treated as its own individual vector in code.</p>
|
|
<p>An example map { foo: 13, bar: 14 } would be encoded as:</p>
|
|
<div class="highlight"><pre><span></span><code>0 : uint8_t 'b', 'a', 'r', 0
|
|
4 : uint8_t 'f', 'o', 'o', 0
|
|
8 : uint8_t 2 // key vector of size 2
|
|
// key vector offset points here
|
|
9 : uint8_t 9, 6 // offsets to bar_key and foo_key
|
|
11: uint8_t 2, 1 // offset to key vector, and its byte width
|
|
13: uint8_t 2 // value vector of size
|
|
// value vector offset points here
|
|
14: uint8_t 14, 13 // values
|
|
16: uint8_t 4, 4 // types
|
|
</code></pre></div>
|
|
<h3 id="the-root">The root</h3>
|
|
<p>As mentioned, the root starts at the end of the buffer.
|
|
The last uint8_t is the width in bytes of the root (normally the parent
|
|
determines the width, but the root has no parent). The uint8_t before this is
|
|
the type of the root, and the bytes before that are the root value (of the
|
|
number of bytes specified by the last byte).</p>
|
|
<p>So for example, the integer value <code>13</code> as root would be:</p>
|
|
<div class="highlight"><pre><span></span><code>uint8_t 13, 4, 1 // Value, type, root byte width.
|
|
</code></pre></div>
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
</article>
|
|
</div>
|
|
|
|
|
|
<script>var tabs=__md_get("__tabs");if(Array.isArray(tabs))e:for(var set of document.querySelectorAll(".tabbed-set")){var labels=set.querySelector(".tabbed-labels");for(var tab of tabs)for(var label of labels.getElementsByTagName("label"))if(label.innerText.trim()===tab){var input=document.getElementById(label.htmlFor);input.checked=!0;continue e}}</script>
|
|
|
|
<script>var target=document.getElementById(location.hash.slice(1));target&&target.name&&(target.checked=target.name.startsWith("__tabbed_"))</script>
|
|
</div>
|
|
|
|
</main>
|
|
|
|
<footer class="md-footer">
|
|
|
|
|
|
|
|
<nav class="md-footer__inner md-grid" aria-label="Footer" >
|
|
|
|
|
|
<a href="../white_paper/" class="md-footer__link md-footer__link--prev" aria-label="Previous: White Paper">
|
|
<div class="md-footer__button md-icon">
|
|
|
|
<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 24 24"><path d="M20 11v2H8l5.5 5.5-1.42 1.42L4.16 12l7.92-7.92L13.5 5.5 8 11z"/></svg>
|
|
</div>
|
|
<div class="md-footer__title">
|
|
<span class="md-footer__direction">
|
|
Previous
|
|
</span>
|
|
<div class="md-ellipsis">
|
|
White Paper
|
|
</div>
|
|
</div>
|
|
</a>
|
|
|
|
|
|
|
|
<a href="../intermediate_representation/" class="md-footer__link md-footer__link--next" aria-label="Next: Intermediate Representation">
|
|
<div class="md-footer__title">
|
|
<span class="md-footer__direction">
|
|
Next
|
|
</span>
|
|
<div class="md-ellipsis">
|
|
Intermediate Representation
|
|
</div>
|
|
</div>
|
|
<div class="md-footer__button md-icon">
|
|
|
|
<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 24 24"><path d="M4 11v2h12l-5.5 5.5 1.42 1.42L19.84 12l-7.92-7.92L10.5 5.5 16 11z"/></svg>
|
|
</div>
|
|
</a>
|
|
|
|
</nav>
|
|
|
|
|
|
<div class="md-footer-meta md-typeset">
|
|
<div class="md-footer-meta__inner md-grid">
|
|
<div class="md-copyright">
|
|
|
|
<div class="md-copyright__highlight">
|
|
Copyright © 2025 Google
|
|
</div>
|
|
|
|
|
|
Made with
|
|
<a href="https://squidfunk.github.io/mkdocs-material/" target="_blank" rel="noopener">
|
|
Material for MkDocs
|
|
</a>
|
|
|
|
</div>
|
|
|
|
|
|
<div class="md-social">
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
<a href="https://github.com/google/flatbuffers" target="_blank" rel="noopener" title="github.com" class="md-social__link">
|
|
<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 512 512"><!--! Font Awesome Free 7.1.0 by @fontawesome - https://fontawesome.com License - https://fontawesome.com/license/free (Icons: CC BY 4.0, Fonts: SIL OFL 1.1, Code: MIT License) Copyright 2025 Fonticons, Inc.--><path d="M173.9 397.4c0 2-2.3 3.6-5.2 3.6-3.3.3-5.6-1.3-5.6-3.6 0-2 2.3-3.6 5.2-3.6 3-.3 5.6 1.3 5.6 3.6m-31.1-4.5c-.7 2 1.3 4.3 4.3 4.9 2.6 1 5.6 0 6.2-2s-1.3-4.3-4.3-5.2c-2.6-.7-5.5.3-6.2 2.3m44.2-1.7c-2.9.7-4.9 2.6-4.6 4.9.3 2 2.9 3.3 5.9 2.6 2.9-.7 4.9-2.6 4.6-4.6-.3-1.9-3-3.2-5.9-2.9M252.8 8C114.1 8 8 113.3 8 252c0 110.9 69.8 205.8 169.5 239.2 12.8 2.3 17.3-5.6 17.3-12.1 0-6.2-.3-40.4-.3-61.4 0 0-70 15-84.7-29.8 0 0-11.4-29.1-27.8-36.6 0 0-22.9-15.7 1.6-15.4 0 0 24.9 2 38.6 25.8 21.9 38.6 58.6 27.5 72.9 20.9 2.3-16 8.8-27.1 16-33.7-55.9-6.2-112.3-14.3-112.3-110.5 0-27.5 7.6-41.3 23.6-58.9-2.6-6.5-11.1-33.3 2.6-67.9 20.9-6.5 69 27 69 27 20-5.6 41.5-8.5 62.8-8.5s42.8 2.9 62.8 8.5c0 0 48.1-33.6 69-27 13.7 34.7 5.2 61.4 2.6 67.9 16 17.7 25.8 31.5 25.8 58.9 0 96.5-58.9 104.2-114.8 110.5 9.2 7.9 17 22.9 17 46.4 0 33.7-.3 75.4-.3 83.6 0 6.5 4.6 14.4 17.3 12.1C436.2 457.8 504 362.9 504 252 504 113.3 391.5 8 252.8 8M105.2 352.9c-1.3 1-1 3.3.7 5.2 1.6 1.6 3.9 2.3 5.2 1 1.3-1 1-3.3-.7-5.2-1.6-1.6-3.9-2.3-5.2-1m-10.8-8.1c-.7 1.3.3 2.9 2.3 3.9 1.6 1 3.6.7 4.3-.7.7-1.3-.3-2.9-2.3-3.9-2-.6-3.6-.3-4.3.7m32.4 35.6c-1.6 1.3-1 4.3 1.3 6.2 2.3 2.3 5.2 2.6 6.5 1 1.3-1.3.7-4.3-1.3-6.2-2.2-2.3-5.2-2.6-6.5-1m-11.4-14.7c-1.6 1-1.6 3.6 0 5.9s4.3 3.3 5.6 2.3c1.6-1.3 1.6-3.9 0-6.2-1.4-2.3-4-3.3-5.6-2"/></svg>
|
|
</a>
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
<a href="https:///discord.gg/6qgKs3R" target="_blank" rel="noopener" title="" class="md-social__link">
|
|
<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 576 512"><!--! Font Awesome Free 7.1.0 by @fontawesome - https://fontawesome.com License - https://fontawesome.com/license/free (Icons: CC BY 4.0, Fonts: SIL OFL 1.1, Code: MIT License) Copyright 2025 Fonticons, Inc.--><path d="M492.5 69.8c-.2-.3-.4-.6-.8-.7-38.1-17.5-78.4-30-119.7-37.1-.4-.1-.8 0-1.1.1s-.6.4-.8.8c-5.5 9.9-10.5 20.2-14.9 30.6-44.6-6.8-89.9-6.8-134.4 0-4.5-10.5-9.5-20.7-15.1-30.6-.2-.3-.5-.6-.8-.8s-.7-.2-1.1-.2C162.5 39 122.2 51.5 84.1 69c-.3.1-.6.4-.8.7C7.1 183.5-13.8 294.6-3.6 404.2c0 .3.1.5.2.8s.3.4.5.6c44.4 32.9 94 58 146.8 74.2.4.1.8.1 1.1 0s.7-.4.9-.7c11.3-15.4 21.4-31.8 30-48.8.1-.2.2-.5.2-.8s0-.5-.1-.8-.2-.5-.4-.6-.4-.3-.7-.4c-15.8-6.1-31.2-13.4-45.9-21.9-.3-.2-.5-.4-.7-.6s-.3-.6-.3-.9 0-.6.2-.9.3-.5.6-.7c3.1-2.3 6.2-4.7 9.1-7.1.3-.2.6-.4.9-.4s.7 0 1 .1c96.2 43.9 200.4 43.9 295.5 0 .3-.1.7-.2 1-.2s.7.2.9.4c2.9 2.4 6 4.9 9.1 7.2.2.2.4.4.6.7s.2.6.2.9-.1.6-.3.9-.4.5-.6.6c-14.7 8.6-30 15.9-45.9 21.8-.2.1-.5.2-.7.4s-.3.4-.4.7-.1.5-.1.8.1.5.2.8c8.8 17 18.8 33.3 30 48.8.2.3.6.6.9.7s.8.1 1.1 0c52.9-16.2 102.6-41.3 147.1-74.2.2-.2.4-.4.5-.6s.2-.5.2-.8c12.3-126.8-20.5-236.9-86.9-334.5zm-302 267.7c-29 0-52.8-26.6-52.8-59.2s23.4-59.2 52.8-59.2c29.7 0 53.3 26.8 52.8 59.2 0 32.7-23.4 59.2-52.8 59.2m195.4 0c-29 0-52.8-26.6-52.8-59.2s23.4-59.2 52.8-59.2c29.7 0 53.3 26.8 52.8 59.2 0 32.7-23.2 59.2-52.8 59.2"/></svg>
|
|
</a>
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
<a href="https://twitter.com/dbaileychess" target="_blank" rel="noopener" title="twitter.com" class="md-social__link">
|
|
<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 448 512"><!--! Font Awesome Free 7.1.0 by @fontawesome - https://fontawesome.com License - https://fontawesome.com/license/free (Icons: CC BY 4.0, Fonts: SIL OFL 1.1, Code: MIT License) Copyright 2025 Fonticons, Inc.--><path d="M357.2 48h70.6L273.6 224.2 455 464H313L201.7 318.6 74.5 464H3.8l164.9-188.5L-5.2 48h145.6l100.5 132.9zm-24.8 373.8h39.1L119.1 88h-42z"/></svg>
|
|
</a>
|
|
|
|
</div>
|
|
|
|
</div>
|
|
</div>
|
|
</footer>
|
|
|
|
</div>
|
|
<div class="md-dialog" data-md-component="dialog">
|
|
<div class="md-dialog__inner md-typeset"></div>
|
|
</div>
|
|
|
|
|
|
|
|
|
|
|
|
<script id="__config" type="application/json">{"annotate": null, "base": "..", "features": ["content.code.annotate", "content.tabs.link", "navigation.expand", "navigation.footer", "header.autohide", "content.action.edit"], "search": "../assets/javascripts/workers/search.2c215733.min.js", "tags": null, "translations": {"clipboard.copied": "Copied to clipboard", "clipboard.copy": "Copy to clipboard", "search.result.more.one": "1 more on this page", "search.result.more.other": "# more on this page", "search.result.none": "No matching documents", "search.result.one": "1 matching document", "search.result.other": "# matching documents", "search.result.placeholder": "Type to start searching", "search.result.term.missing": "Missing", "select.version": "Select version"}, "version": null}</script>
|
|
|
|
|
|
<script src="../assets/javascripts/bundle.79ae519e.min.js"></script>
|
|
|
|
|
|
</body>
|
|
</html> |