Coding Standard for the ANGLE Project

Google Style Guide

We generally use the [Google C++ Style Guide] ( as a basis for our Coding Standard, however we will deviate from it in a few areas, as noted below.

Items marked {DEV} indicate a deviation from the Google guidelines. Items marked {DO} are reiterating points from the Google guidelines.

Before you upload code to Gerrit, use git cl format to auto-format your code. This will catch most of the trivial formatting errors and save you time.

Header Files

  • We will use .h for C++ headers.
  • {DEV} #define guards should be of the form: <PATH>_<FILE>_H_. (Compiler codebase is varied, including <PROJECT>_ makes the names excessively long).


  • {DO} avoid globally scoped variables, unless absolutely necessary.


  • {DEV} Inherit (privately) from angle::NonCopyable helper class (defined in common/angleutils.h) to disable default copy and assignment operators.

Other C++ Features

  • {DEV} all parameters passed by reference, except for STL containers (e.g. std::vector, std::list), must be labeled const. For return parameters other than STL containers, use a pointer.
  • {DO} avoid use of default arguments.
  • {DONT} use C++ exceptions, they are disabled in the builds and not caught.
  • {DO} use nullptr (instead of 0 or NULL) for pointers.
  • {DO} use size_t for loop iterators and size values.
  • {DO} use uint8_t pointers instead of void pointers to denote binary data.
  • {DO} use C++11 according to the [Chromium guide on C++11] (


File Names

  • {DEV} Filenames should be all lowercase and can include underscores (_). If the file is an implementation of a class, the filename may be capitalized the same as the major class.
  • {DEV} We use .cpp (instead of .cc), .h and .inl (inlined files) for C++ files and headers.

Directory Names

  • Directory names should be all lowercase, unless following an externally imposed capitalization (eg include/EGL, or src/libGLESv2, etc)

Variable Names

Use the following guidelines, they do deviate somewhat from the Google guidelines.

  • class and type names: start with capital letter and use CamelCase.
  • {DEV} class member variables: use an m prefix instead of trailing underscore and use CamelCase.
  • global variables (if they must be used): use a g_ prefix.
  • {DEV} variable names: start with lower case and use CamelCase (chosen for consistency)
  • {DEV} function names: Member functions start with lower case and use CamelCase. Non-member functions start with capital letter and use CamelCase (chosen for consistency)
  • Constants: start with a k and use CamelCase
  • namespaces: use all lower case
  • Enum Names - use class enums, and the values should be uppercase with underscores.
  • macros: all uppercase with underscores
  • exceptions to naming: use common sense!


  • {DO} read and follow Google's recommendations.
  • Each file must start with the following boilerplate notice:
//  Copyright (c) 2016 The ANGLE Project Authors. All rights reserved.
//  Use of this source code is governed by a BSD-style license that can be
//  found in the LICENSE file.


  • {DEV} Avoid excessively long lines. Please keep lines under 100 columns long.
  • Use unix-style newlines.
  • {DO} use only spaces. No tab characters. Configure your editor to emit spaces when you hit the TAB-key.
  • {DEV} indent 4 spaces at a time.
  • conditionals: place space outside the parenthesis. No spaces inside.
  • switch statements: use the output of git cl format.
  • class format(eg private, public, protected): indent by 2 spaces. Regular 4-space indent from the outer scope for declarations/definitions.
  • pointers and references: * and & tight against the variable
  • namespaces: are not indented.
  • extern code blocks: are not indented.
  • {DEV} braces should go on a separate line, except for functions defined in a header file where the whole function declaration and definition fit on one line.


if (conditional)
switch (conditional)
  case foo:
  case bar:
class MyClass : public Foo
    ~MyClass() {};
char *c;
const string &str;

Exceptions to the Rules

  • If modifying pre-existing code that does not match the standard, the altered portions of the code should be changed to match the standard.