src/video/x11/SDL_x11opengles.c
author Sam Lantinga <slouken@libsdl.org>
Wed, 18 Jul 2012 15:17:27 -0700
changeset 6370 93187f7f7d5d
parent 6368 fcbbd0e2da5e
child 6373 494e0436525f
permissions -rwxr-xr-x
Improved simultaneous support for OpenGL and OpenGL ES From Scott Percival Okay, I think I have something for this. Tested it on GL and GLES machines, it seems to work okay. - Add a new SDL GL attribute SDL_GL_CONTEXT_EGL: - Only useful for the X11 video driver at the moment - Set to 1 for an EGL context, 0 to use the default for the video driver - Default is 0, unless library is built for EGL only - Should be set after SDL init, but before window/context creation (i.e. same place you'd specify attributes for major/minor GL version) - After a lot of agony pondering the least-terrible way to go about it, made it so that X11_GL_LoadLibrary and X11_GLES_LoadLibrary check SDL_GL_CONTEXT_EGL. If no GL context exists yet, and the attribute choice doesn't match with the checking function, then it changes all the function pointers in the video driver and passes control on to the new LoadLibrary method. - Likewise, make X11_CreateWindow check this attribute before firing off a call to X11_GL_GetVisual/X11_GLES_GetVisual - Added a sanity check to the start of X11_GL_LoadLibrary - Tidied up SDL_x11opengles.h - Moved ownership of the gles_data structure over to X11_GLES_LoadLibrary/UnloadLibrary - Should incorporate the 3 fixes posted by Andre Heider This is obviously quite a bit to take in, but is (at least) a proof of concept for the approach I think EGL/GLX mingling should take. Any comments/criticism is much appreciated.

/*
  Simple DirectMedia Layer
  Copyright (C) 1997-2012 Sam Lantinga <slouken@libsdl.org>

  This software is provided 'as-is', without any express or implied
  warranty.  In no event will the authors be held liable for any damages
  arising from the use of this software.

  Permission is granted to anyone to use this software for any purpose,
  including commercial applications, and to alter it and redistribute it
  freely, subject to the following restrictions:

  1. The origin of this software must not be misrepresented; you must not
     claim that you wrote the original software. If you use this software
     in a product, an acknowledgment in the product documentation would be
     appreciated but is not required.
  2. Altered source versions must be plainly marked as such, and must not be
     misrepresented as being the original software.
  3. This notice may not be removed or altered from any source distribution.
*/
#include "SDL_config.h"

#if SDL_VIDEO_DRIVER_X11 && SDL_VIDEO_OPENGL_ES

#include "SDL_x11video.h"
#include "SDL_x11opengles.h"
#include "SDL_x11opengl.h"

#define DEFAULT_EGL "libEGL.so"
#define DEFAULT_OGL_ES2 "libGLESv2.so"
#define DEFAULT_OGL_ES_PVR "libGLES_CM.so"
#define DEFAULT_OGL_ES "libGLESv1_CM.so"

#define LOAD_FUNC(NAME) \
	*((void**)&_this->gles_data->NAME) = dlsym(handle, #NAME); \
	if (!_this->gles_data->NAME) \
	{ \
		SDL_SetError("Could not retrieve EGL function " #NAME); \
		return -1; \
	}

/* GLES implementation of SDL OpenGL support */

void *
X11_GLES_GetProcAddress(_THIS, const char *proc)
{
    static char procname[1024];
    void *handle;
    void *retval;

    handle = _this->gles_data->egl_dll_handle;
    if (_this->gles_data->eglGetProcAddress) {
        retval = _this->gles_data->eglGetProcAddress(proc);
        if (retval) {
            return retval;
        }
    }
    
    handle = _this->gl_config.dll_handle;
#if defined(__OpenBSD__) && !defined(__ELF__)
#undef dlsym(x,y);
#endif
    retval = dlsym(handle, proc);
    if (!retval && strlen(proc) <= 1022) {
        procname[0] = '_';
        strcpy(procname + 1, proc);
        retval = dlsym(handle, procname);
    }
    return retval;
}

void
X11_GLES_UnloadLibrary(_THIS)
{
    if ((_this->gles_data) && (_this->gl_config.driver_loaded)) {
        _this->gles_data->eglTerminate(_this->gles_data->egl_display);

        dlclose(_this->gl_config.dll_handle);
        dlclose(_this->gles_data->egl_dll_handle);

        SDL_free(_this->gles_data);
        _this->gles_data = NULL;

        _this->gl_config.dll_handle = NULL;
        _this->gl_config.driver_loaded = 0;
    }
}

int
X11_GLES_LoadLibrary(_THIS, const char *path)
{
    void *handle;
    int dlopen_flags;

    SDL_VideoData *data = (SDL_VideoData *) _this->driverdata;

    if (_this->gles_data) {
        SDL_SetError("OpenGL ES context already created");
        return -1;
    }

#if SDL_VIDEO_OPENGL_GLX
    /* If SDL_GL_CONTEXT_EGL has been changed to 0, switch over to X11_GL functions  */
    if (_this->gl_config.use_egl == 0) {
        _this->GL_LoadLibrary = X11_GL_LoadLibrary;
        _this->GL_GetProcAddress = X11_GL_GetProcAddress;
        _this->GL_UnloadLibrary = X11_GL_UnloadLibrary;
        _this->GL_CreateContext = X11_GL_CreateContext;
        _this->GL_MakeCurrent = X11_GL_MakeCurrent;
        _this->GL_SetSwapInterval = X11_GL_SetSwapInterval;
        _this->GL_GetSwapInterval = X11_GL_GetSwapInterval;
        _this->GL_SwapWindow = X11_GL_SwapWindow;
        _this->GL_DeleteContext = X11_GL_DeleteContext;
        return X11_GL_LoadLibrary(_this, path);
    }
#endif

#ifdef RTLD_GLOBAL
    dlopen_flags = RTLD_LAZY | RTLD_GLOBAL;
#else
    dlopen_flags = RTLD_LAZY;
#endif
    handle = dlopen(path, dlopen_flags);
    /* Catch the case where the application isn't linked with EGL */
    if ((dlsym(handle, "eglChooseConfig") == NULL) && (path == NULL)) {

        dlclose(handle);
        path = getenv("SDL_VIDEO_EGL_DRIVER");
        if (path == NULL) {
            path = DEFAULT_EGL;
        }
        handle = dlopen(path, dlopen_flags);
    }

    if (handle == NULL) {
        SDL_SetError("Could not load OpenGL ES/EGL library");
        return -1;
    }

    /* Unload the old driver and reset the pointers */
    X11_GLES_UnloadLibrary(_this);

    _this->gles_data = (struct SDL_PrivateGLESData *) SDL_calloc(1, sizeof(SDL_PrivateGLESData));
    if (!_this->gles_data) {
        SDL_OutOfMemory();
        return -1;
    }

    /* Load new function pointers */
    LOAD_FUNC(eglGetDisplay);
    LOAD_FUNC(eglInitialize);
    LOAD_FUNC(eglTerminate);
    LOAD_FUNC(eglGetProcAddress);
    LOAD_FUNC(eglChooseConfig);
    LOAD_FUNC(eglGetConfigAttrib);
    LOAD_FUNC(eglCreateContext);
    LOAD_FUNC(eglDestroyContext);
    LOAD_FUNC(eglCreateWindowSurface);
    LOAD_FUNC(eglDestroySurface);
    LOAD_FUNC(eglMakeCurrent);
    LOAD_FUNC(eglSwapBuffers);
    LOAD_FUNC(eglSwapInterval);

    _this->gles_data->egl_display =
        _this->gles_data->eglGetDisplay((NativeDisplayType) data->display);

    if (!_this->gles_data->egl_display) {
        SDL_SetError("Could not get EGL display");
        return -1;
    }

    if (_this->gles_data->
        eglInitialize(_this->gles_data->egl_display, NULL,
                      NULL) != EGL_TRUE) {
        SDL_SetError("Could not initialize EGL");
        return -1;
    }

    _this->gles_data->egl_dll_handle = handle;

    path = getenv("SDL_VIDEO_GL_DRIVER");
    handle = dlopen(path, dlopen_flags);
    if ((path == NULL) | (handle == NULL)) {
        if (_this->gl_config.major_version > 1) {
            path = DEFAULT_OGL_ES2;
            handle = dlopen(path, dlopen_flags);
        } else {
            path = DEFAULT_OGL_ES;
            handle = dlopen(path, dlopen_flags);
            if (handle == NULL) {
                path = DEFAULT_OGL_ES_PVR;
                handle = dlopen(path, dlopen_flags);
            }
        }
    }

    if (handle == NULL) {
        SDL_SetError("Could not initialize OpenGL ES library");
        return -1;
    }

    _this->gl_config.dll_handle = handle;
    _this->gl_config.driver_loaded = 1;

    if (path) {
        strncpy(_this->gl_config.driver_path, path,
                sizeof(_this->gl_config.driver_path) - 1);
    } else {
        strcpy(_this->gl_config.driver_path, "");
    }
    return 0;
}

XVisualInfo *
X11_GLES_GetVisual(_THIS, Display * display, int screen)
{
    /* 64 seems nice. */
    EGLint attribs[64];
    EGLint found_configs = 0;
    VisualID visual_id;
    int i;

    if (!_this->gles_data) {
        /* The EGL library wasn't loaded, SDL_GetError() should have info */
        return NULL;
    }

    i = 0;
    attribs[i++] = EGL_RED_SIZE;
    attribs[i++] = _this->gl_config.red_size;
    attribs[i++] = EGL_GREEN_SIZE;
    attribs[i++] = _this->gl_config.green_size;
    attribs[i++] = EGL_BLUE_SIZE;
    attribs[i++] = _this->gl_config.blue_size;

    if (_this->gl_config.alpha_size) {
        attribs[i++] = EGL_ALPHA_SIZE;
        attribs[i++] = _this->gl_config.alpha_size;
    }

    if (_this->gl_config.buffer_size) {
        attribs[i++] = EGL_BUFFER_SIZE;
        attribs[i++] = _this->gl_config.buffer_size;
    }

    attribs[i++] = EGL_DEPTH_SIZE;
    attribs[i++] = _this->gl_config.depth_size;

    if (_this->gl_config.stencil_size) {
        attribs[i++] = EGL_STENCIL_SIZE;
        attribs[i++] = _this->gl_config.stencil_size;
    }

    if (_this->gl_config.multisamplebuffers) {
        attribs[i++] = EGL_SAMPLE_BUFFERS;
        attribs[i++] = _this->gl_config.multisamplebuffers;
    }

    if (_this->gl_config.multisamplesamples) {
        attribs[i++] = EGL_SAMPLES;
        attribs[i++] = _this->gl_config.multisamplesamples;
    }

    attribs[i++] = EGL_RENDERABLE_TYPE;
    if (_this->gl_config.major_version == 2) {
        attribs[i++] = EGL_OPENGL_ES2_BIT;
    } else {
        attribs[i++] = EGL_OPENGL_ES_BIT;
    }

    attribs[i++] = EGL_NONE;

    if (_this->gles_data->eglChooseConfig(_this->gles_data->egl_display,
                                          attribs,
                                          &_this->gles_data->egl_config, 1,
                                          &found_configs) == EGL_FALSE ||
        found_configs == 0) {
        SDL_SetError("Couldn't find matching EGL config");
        return NULL;
    }

    if (_this->gles_data->eglGetConfigAttrib(_this->gles_data->egl_display,
                                             _this->gles_data->egl_config,
                                             EGL_NATIVE_VISUAL_ID,
                                             (EGLint *) & visual_id) ==
        EGL_FALSE || !visual_id) {
        /* Use the default visual when all else fails */
        XVisualInfo vi_in;
        int out_count;
        vi_in.screen = screen;

        _this->gles_data->egl_visualinfo = XGetVisualInfo(display,
                                                          VisualScreenMask,
                                                          &vi_in, &out_count);
    } else {
        XVisualInfo vi_in;
        int out_count;

        vi_in.screen = screen;
        vi_in.visualid = visual_id;
        _this->gles_data->egl_visualinfo = XGetVisualInfo(display,
                                                          VisualScreenMask |
                                                          VisualIDMask,
                                                          &vi_in, &out_count);
    }

    return _this->gles_data->egl_visualinfo;
}

SDL_GLContext
X11_GLES_CreateContext(_THIS, SDL_Window * window)
{
    EGLint context_attrib_list[] = {
        EGL_CONTEXT_CLIENT_VERSION,
        1,
        EGL_NONE
    };

    SDL_WindowData *data = (SDL_WindowData *) window->driverdata;
    Display *display = data->videodata->display;
    SDL_GLContext context = 1;

    XSync(display, False);

    if (_this->gl_config.major_version) {
        context_attrib_list[1] = _this->gl_config.major_version;
    }

    _this->gles_data->egl_context =
        _this->gles_data->eglCreateContext(_this->gles_data->egl_display,
                                           _this->gles_data->egl_config,
                                           EGL_NO_CONTEXT, context_attrib_list);
    XSync(display, False);

    if (_this->gles_data->egl_context == EGL_NO_CONTEXT) {
        SDL_SetError("Could not create EGL context");
        return NULL;
    }

    _this->gles_data->egl_swapinterval = 0;

    if (X11_GLES_MakeCurrent(_this, window, context) < 0) {
        X11_GLES_DeleteContext(_this, context);
        return NULL;
    }

    return context;
}

int
X11_GLES_MakeCurrent(_THIS, SDL_Window * window, SDL_GLContext context)
{
    int retval;

//    SDL_WindowData *data = (SDL_WindowData *) window->driverdata;
//    Display *display = data->videodata->display;

    retval = 1;
    if (!_this->gles_data->eglMakeCurrent(_this->gles_data->egl_display,
                                          _this->gles_data->egl_surface,
                                          _this->gles_data->egl_surface,
                                          _this->gles_data->egl_context)) {
        SDL_SetError("Unable to make EGL context current");
        retval = -1;
    }
//    XSync(display, False);

    return (retval);
}

int
X11_GLES_SetSwapInterval(_THIS, int interval)
{
    if (_this->gles_data) {
        SDL_SetError("OpenGL ES context not active");
        return -1;
    }

    EGLBoolean status;
    status = _this->gles_data->eglSwapInterval(_this->gles_data->egl_display, interval);
    if (status == EGL_TRUE) {
        _this->gles_data->egl_swapinterval = interval;
        return 0; 
    }

    SDL_SetError("Unable to set the EGL swap interval");
    return -1;
}

int
X11_GLES_GetSwapInterval(_THIS)
{
    if (_this->gles_data) {
        SDL_SetError("OpenGL ES context not active");
        return -1;
    }

    return _this->gles_data->egl_swapinterval;
}

void
X11_GLES_SwapWindow(_THIS, SDL_Window * window)
{
    _this->gles_data->eglSwapBuffers(_this->gles_data->egl_display,
                                     _this->gles_data->egl_surface);
}

void
X11_GLES_DeleteContext(_THIS, SDL_GLContext context)
{
    /* Clean up GLES and EGL */
    if (_this->gles_data) {  
        if (_this->gles_data->egl_context != EGL_NO_CONTEXT ||
            _this->gles_data->egl_surface != EGL_NO_SURFACE) {
            _this->gles_data->eglMakeCurrent(_this->gles_data->egl_display,
                                             EGL_NO_SURFACE, EGL_NO_SURFACE,
                                             EGL_NO_CONTEXT);

            if (_this->gles_data->egl_context != EGL_NO_CONTEXT) {
                _this->gles_data->eglDestroyContext(_this->gles_data->egl_display,
                                                    _this->gles_data->
                                                    egl_context);
                _this->gles_data->egl_context = EGL_NO_CONTEXT;
            }

            if (_this->gles_data->egl_surface != EGL_NO_SURFACE) {
                _this->gles_data->eglDestroySurface(_this->gles_data->egl_display,
                                                    _this->gles_data->
                                                    egl_surface);
                _this->gles_data->egl_surface = EGL_NO_SURFACE;
            }
        }

        /* crappy fix */
        X11_GLES_UnloadLibrary(_this);
    }

}

#endif /* SDL_VIDEO_DRIVER_X11 && SDL_VIDEO_OPENGL_ES */

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