README.txt
author Sam Lantinga <slouken@libsdl.org>
Wed, 18 Oct 2017 08:52:04 -0700
changeset 11630 ad4b5d85edee
parent 10890 a2ec89f77e6b
permissions -rw-r--r--
Fixed bug 3821 - Allow SDL_CreateWindow and SDL_CreateRenderer with OpenGL ES 3.0 (GLES3) for Angle (Windows)

Carlos

Angle supports GLES3 but when using these functions (SDL_CreateWindow and SDL_CreateRenderer), defaults again to GLES2.0.

A current workaround (hack) to retrieve a GLES3.0 context with Angle is:

1) set

SDL_GL_SetAttribute(SDL_GL_CONTEXT_MAJOR_VERSION, 3);
SDL_GL_SetAttribute(SDL_GL_CONTEXT_MINOR_VERSION, 0);

after InitSDL AND after calling SDL_CreateWindow (before SDL_CreateRenderer)

2) Comment lines 2032-2044 in SDL_render_gles2.c, funtion GLES2_CreateRenderer

window_flags = SDL_GetWindowFlags(window);
if (!(window_flags & SDL_WINDOW_OPENGL) ||
profile_mask != SDL_GL_CONTEXT_PROFILE_ES || major != RENDERER_CONTEXT_MAJOR || minor != RENDERER_CONTEXT_MINOR) {

changed_window = SDL_TRUE;
SDL_GL_SetAttribute(SDL_GL_CONTEXT_PROFILE_MASK, SDL_GL_CONTEXT_PROFILE_ES);
SDL_GL_SetAttribute(SDL_GL_CONTEXT_MAJOR_VERSION, RENDERER_CONTEXT_MAJOR);
SDL_GL_SetAttribute(SDL_GL_CONTEXT_MINOR_VERSION, RENDERER_CONTEXT_MINOR);

if (SDL_RecreateWindow(window, window_flags | SDL_WINDOW_OPENGL) < 0) {
goto error;
}
}

This retrives a GLES3 context as confirmed using glGetString(GL_VERSION). This should be fixed by modifying a few if's.
     1 
     2                          Simple DirectMedia Layer
     3 
     4                                   (SDL)
     5 
     6                                 Version 2.0
     7 
     8 ---
     9 https://www.libsdl.org/
    10 
    11 Simple DirectMedia Layer is a cross-platform development library designed
    12 to provide low level access to audio, keyboard, mouse, joystick, and graphics
    13 hardware via OpenGL and Direct3D. It is used by video playback software,
    14 emulators, and popular games including Valve's award winning catalog
    15 and many Humble Bundle games.
    16 
    17 More extensive documentation is available in the docs directory, starting
    18 with README.md
    19 
    20 Enjoy!
    21 	Sam Lantinga				(slouken@libsdl.org)