libegl
#ABOUT
libegl is an EGL implementation targeting Apple iOS platform.
#MOTIVATION:
I am writing cross-platform C/C++ libraries and I needed an EGL implementation for my iPhone port.
EGL provides mechanisms for creating rendering surfaces onto which client APIs like OpenGL ES and OpenVG can draw, creates graphics contexts for client APIs, and synchronizes drawing by client APIs as well as native platform rendering APIs. This enables seamless rendering using both OpenGL ES and OpenVG for high-performance, accelerated, mixed-mode 2D and 3D rendering. Khronos Group
Please refer to official Khronos Group website for further details about EGL. Especially Khronos EGL Registry .
#DOCUMENTATION
The source code is partially documented although EAGL iOS driver aims to be fully documented in the near future.
Major design decisions are documented.
##How to get started on iOS ?
###How to compile the library ?
cd proj && make build-all-release
###Build flavors
cd proj && make usage
###Where are the compilation artifacts ?
Upon sucessful project compilation, directory "prefix" will contains:
- static library .a file for your project to link with.
- EGL header files declaring EGL functions
###What are the dependencies/linker settings required to link with ?
Static library .a file requires:
- to be linked with:
- OpenGLES.framework
- CoreGraphics.framework
- UIKit.framework
- QuartzCore.framework
- to have the following PREPROCESSOR macros defined:
- HAVE_PTHREAD=1
- _EGL_NATIVE_PLATFORM=_EGL_PLATFORM_IOS
- _EGL_OS_APPLE_IOS=1
- _EGL_BUILT_IN_DRIVER_IOSEAGL=1
- DEBUG=1 (optional)
The code is fully compatible with MRR. ARC support is on the way.
#SOURCE
Main source repository:
https://github.com/davidandreoletti/libegl
#DEVELOPMENT STATUS
This implementation is in ALPHA version. I only implements features required for my own needs but feel free to extend it. The tables below describes what is supported in this implementation.
##Nomenclature
- Supported: The feature is implemented and fully/partially tested
- unsupported: The feature is not implemented due to either technically infeasibility OR not yet planned
- planned: The feature will be implemented for a future release
| iOS SDK Version | Status |
|---|---|
| 4.3+ | Supported |
###EGL API version supported
| EGL API Version | Status |
|---|---|
| 1.4 | Supported |
###Datatypes
| EGL datatype | Support Status | iOS datatype | Details |
|---|---|---|---|
| EGLNativeDisplayType | Supported | UIWindow* | |
| EGLNativePixmapType | Unsupported | NA | |
| EGLNativeWindowType | Supported | CAEAGLayer |
###Client APIs
| Client API | Support Status | Details |
|---|---|---|
| EGL_OPENGL_ES_BIT | Supported | |
| EGL_OPENGL_ES2_BIT | Supported | |
| EGL_OPENGL_ES3_BIT_KHR | Supported | See "EGL_KHR_create_context" EGL extension |
| EGL_OPENGL_BIT | Unsupported | |
| EGL_OPENVG_BIT | Unsupported |
###EGL Functions
| Functions | Support Status | Details |
|---|---|---|
| eglGetDisplay | Supported | |
| eglInitialize | Supported | |
| eglQueryString | Supported | |
| eglGetConfigs | Supported | |
| eglChooseConfig | Supported | |
| eglBindAPI | Supported | |
| eglCreateContext | Supported | |
| eglDestroyContext | Supported | |
| eglCreateWindowSurface | Supported | EGLNativeWindowType MUST remain valid for as long as the EGLSurface handle is valid. The surface dimensions (in pixel) equals EGLNativeWindowType's contentScaleFactor * EGLNativeWindowType's frame |
| eglCreatePbufferSurface | Unsupported | |
| eglCreatePixmapSurface | Unsupported | |
| eglDestroySurface | Supported | |
| eglQuerySurface | Supported | |
| eglQueryAPI | Supported | |
| eglQueryContext | Supported | |
| eglSurfaceAttrib | Planned | |
| eglMakeCurrent | Partially supported | EGLSurface read and EGLSurface draw must be the same |
| eglGetCurrentContext | Supported | |
| eglGetCurrentSurface | Supported | |
| eglGetCurrentDisplay | Supported | |
| eglGetConfigAttrib | Supported | |
| eglSwapBuffers | Supported | |
| eglSwapInterval | Supported | |
| eglWaitClient | Supported | |
| eglWaitGL | Supported | |
| eglWaitNative | Unsupported | |
| eglBindTexImage | Unsupported | |
| eglReleaseTexImage | Unsupported | |
| eglCopyBuffers | Unsupported | |
| eglCreatePbufferFromClientBuffer | Unsupported | |
| eglSwapInterval | Supported | |
| eglGetProcAddress | Planned | |
| eglGetError | Supported | |
| eglReleaseThread | Supported | |
| eglTerminate | Planned |
##EGL Extensions
Only attribute EGL_OPENGL_ES3_BIT_KHR is supported. Anything else has not been tested and most likely not supported.
#TESTING
See "test" directory
#SAMPLES
See "samples" directory.
#FAQ
See FAQ.md file
#KNOWN BUGS & MISSING FEATURES LISTS
See README-DEV.md file
#CHANGELOG & REQUIREMENTS
See this file and CHANGELOG file
#DONATING
Gittip:
Bitcoin:
1DaE8Dq4rm9XQKh2Po4pskiwZK526r4xUT
#CONTRIBUTORS:
If you would like to contribute, feel free to drop me an email or contribute patches/pull requests.
#AUTHOR
- David Andreoletti http://davidandreoletti.com
#THANKS TO
- Mesa 3D Graphic Library
This port is greatly inpired from their implementation.
Special thanks to you guys :)
- Changeset used: 56ea2c4816dbcdbdabe7718423828fdb2ee1c95b
- Alexei Sholik's iOS EGL prototype - This implementation did show me it was technically possible.