Overview

At WWDC 2014, Apple introduced a new graphics technology, Metal, for game developers. Metal is a low-level API written in C++. It represents Apple's latest graphics API design. Unlike OpenGL, Metal is not cross-platform. It is an API designed specifically for Apple's latest hardware architecture, so it can boost rendering performance by up to 10x for 3D graphics. Since Apple will deprecate OpenGL, Cocos2d-x v4 adopts Metal for it's rendering engine on Apple platforms. If metal, is unavailable on your platform, OpenGL will then be used to render.

How to run

Mac: use cocos command or CMake
iOS: use CMake to generate Xcode project, then run
Android: use cocos command or Android Studio
Windows: use cocos command or CMake
Linux: use cocos command or CMake

A CMake tutorial is available.

About How to migrate.

For more detailed interface changes, please refer to API Reference.

Director

Removed the following interfaces

CC_DEPRECATED_ATTRIBUTE static Director* sharedDirector();
void setAlphaBlending(bool on);
void setDepthTest(bool on);
void pushProjectionMatrix(size_t index);
void popProjectionMatrix(size_t index);
void loadProjectionIdentityMatrix(size_t index);
void loadProjectionMatrix(const Mat4& mat, size_t index);
void multiplyProjectionMatrix(const Mat4& mat, size_t index);
const Mat4& getProjectionMatrix(size_t index) const;
void initProjectionMatrixStack(size_t stackCount);
size_t getProjectionMatrixStackSize();

Removed the void setDepthTest(bool on) interface, set by Director::getInstance()->getRenderer()->setDepthTest(true).

Renderer

The backend layer has been added under Renderer, where the metal-related adaptation files are placed under the Metal folder, and the files related to OpenGL ES rendering are placed in the opengl folder. In principle, the graphics API under any platform is not allowed to be used directly except for the source code under the two folders metal and OpenGL.

Renderer
│ CCxxx.h
│ CCxxx.cpp
| ...
└───backend
│ │ file011.h
│ │ file011.cpp
│ │ ...
│ └───metal
│ │ filexxxMTL.h
│ │ filexxxMTL.mm
│ │ ...
│ └───opengl
│ │ filexxxGL.h
│ │ filexxxGL.cpp
│ │ ...
└───shaders
│ │ xxx.vert
│ │ xxx.frag
│ │ ...
│ CMakeLists.txt

Shader and Program

Added GLProgramState, GLProgram, and backend::ProgramState. Example 1, Example 2 demonstrates how to create and use backend::ProgramState.

Metal uses MSL as the shader development language. To support the OpenGL ES shader running on the Metal framework, V4 uses glsl-optimizer to convert the OpenGL ES shader to a Metal MSL shader.

V4 moves the shader file originally stored in renderer/ path with ccShader_ to the renderer/shaders/ path, except that the shader file name is slightly modified (deleted ccShader_), The uniform and texture are explicitly declared in the shader file, not the attributes, uniform and texutre names predefined in GLProgram.

Texture2D

Remove Texture2D::PixelFormat and use backend::PixelFormat under Types.h.
Remove the use of the OpenGL ES API from the source code.
Removed convertXXX to use the convertXXX interface under CCTextureUtils.h.

Removed the following interface

CC_DEPRECATED_ATTRIBUTE const char* stringForFormat() const;
CC_DEPRECATED_ATTRIBUTE unsigned int bitsPerPixelForFormat() const;
CC_DEPRECATED_ATTRIBUTE unsigned int bitsPerPixelForFormat(Texture2D::PixelFormat format) const;
GLuint getName() const;
void setGLProgram(GLProgram* program);
GLProgram* getGLProgram() const;

Added the following interface to set the render texture.

bool initWithBackendTexture(backend::TextureBackend* texture);
void setRenderTarget(bool renderTarget);
inline bool isRenderTarget() const;

Remove the OpenGL texture object(GLuint _name) and use backend::Texture2DBackend* _texture as the texture object.

v4 Upgrade Guide