/*

 * Copyright (C) 2009 Splitted-Desktop Systems. All Rights Reserved.

 *

 * Permission is hereby granted, free of charge, to any person obtaining a

 * copy of this software and associated documentation files (the

 * "Software"), to deal in the Software without restriction, including

 * without limitation the rights to use, copy, modify, merge, publish,

 * distribute, sub license, and/or sell copies of the Software, and to

 * permit persons to whom the Software is furnished to do so, subject to

 * the following conditions:

 * 

 * The above copyright notice and this permission notice (including the

 * next paragraph) shall be included in all copies or substantial portions

 * of the Software.

 * 

 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS

 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF

 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.

 * IN NO EVENT SHALL PRECISION INSIGHT AND/OR ITS SUPPLIERS BE LIABLE FOR

 * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,

 * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE

 * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

 */

#define _GNU_SOURCE 1

#include "sysdeps.h"

#include "va_glx_private.h"

#include "va_glx_impl.h"

#include <stdio.h>

#include <stdlib.h>

#include <stdarg.h>

#include <string.h>

#include <assert.h>

#include <dlfcn.h>

static void va_glx_error_message(const char *format, ...)

{

    va_list args;

    va_start(args, format);

    fprintf(stderr, "libva-glx error: ");

    vfprintf(stderr, format, args);

    va_end(args);

}

// X error trap

static int x11_error_code = 0;

static int (*old_error_handler)(Display *, XErrorEvent *);

static int error_handler(Display *dpy, XErrorEvent *error)

{

    x11_error_code = error->error_code;

    return 0;

}

static void x11_trap_errors(void)

{

    x11_error_code    = 0;

    old_error_handler = XSetErrorHandler(error_handler);

}

static int x11_untrap_errors(void)

{

    XSetErrorHandler(old_error_handler);

    return x11_error_code;

}

// Returns a string representation of an OpenGL error

static const char *gl_get_error_string(GLenum error)

{

    static const struct {

        GLenum val;

        const char *str;

    }

    gl_errors[] = {

        { GL_NO_ERROR,          "no error" },

        { GL_INVALID_ENUM,      "invalid enumerant" },

        { GL_INVALID_VALUE,     "invalid value" },

        { GL_INVALID_OPERATION, "invalid operation" },

        { GL_STACK_OVERFLOW,    "stack overflow" },

        { GL_STACK_UNDERFLOW,   "stack underflow" },

        { GL_OUT_OF_MEMORY,     "out of memory" },

#ifdef GL_INVALID_FRAMEBUFFER_OPERATION_EXT

        { GL_INVALID_FRAMEBUFFER_OPERATION_EXT, "invalid framebuffer operation" },

#endif

        { ~0, NULL }

    };

    int i;

    for (i = 0; gl_errors[i].str; i++) {

        if (gl_errors[i].val == error)

            return gl_errors[i].str;

    }

    return "unknown";

}

static inline int gl_do_check_error(int report)

{

    GLenum error;

    int is_error = 0;

    while ((error = glGetError()) != GL_NO_ERROR) {

        if (report)

            va_glx_error_message("glError: %s caught\n",

                                 gl_get_error_string(error));

        is_error = 1;

    }

    return is_error;

}

static inline void gl_purge_errors(void)

{

    gl_do_check_error(0);

}

static inline int gl_check_error(void)

{

    return gl_do_check_error(1);

}

// glGetTexLevelParameteriv() wrapper

static int gl_get_texture_param(GLenum param, unsigned int *pval)

{

    GLint val;

    gl_purge_errors();

    glGetTexLevelParameteriv(GL_TEXTURE_2D, 0, param, &val;;

    if (gl_check_error())

        return 0;

    if (pval)

        *pval = val;

    return 1;

}

// Returns the OpenGL VTable

static inline VAOpenGLVTableP gl_get_vtable(VADriverContextP ctx)

{

    return &VA_DRIVER_CONTEXT_GLX(ctx)->gl_vtable;

}

// Lookup for a GLX function

typedef void (*GLFuncPtr)(void);

typedef GLFuncPtr (*GLXGetProcAddressProc)(const char *);

static GLFuncPtr get_proc_address_default(const char *name)

{

    return NULL;

}

static GLXGetProcAddressProc get_proc_address_func(void)

{

    GLXGetProcAddressProc get_proc_func;

    dlerror();

    get_proc_func = (GLXGetProcAddressProc)

        dlsym(RTLD_DEFAULT, "glXGetProcAddress");

    if (!dlerror())

        return get_proc_func;

    get_proc_func = (GLXGetProcAddressProc)

        dlsym(RTLD_DEFAULT, "glXGetProcAddressARB");

    if (!dlerror())

        return get_proc_func;

    return get_proc_address_default;

}

static inline GLFuncPtr get_proc_address(const char *name)

{

    static GLXGetProcAddressProc get_proc_func = NULL;

    if (!get_proc_func)

        get_proc_func = get_proc_address_func();

    return get_proc_func(name);

}

// Check for GLX extensions (TFP, FBO)

static int check_extension(const char *name, const char *ext)

{

    const char *end;

    int name_len, n;

    if (!name || !ext)

        return 0;

    end = ext + strlen(ext);

    name_len = strlen(name);

    while (ext < end) {

        n = strcspn(ext, " ");

        if (n == name_len && strncmp(name, ext, n) == 0)

            return 1;

        ext += (n + 1);

    }

    return 0;

}

static int check_extension3(const char *name)

{

    int nbExtensions, i;

    PFNGLGETSTRINGIPROC glGetStringi = 0;

    glGetStringi = (PFNGLGETSTRINGIPROC) get_proc_address("glGetStringi");

    if(!glGetStringi)

        return 0;

    glGetIntegerv(GL_NUM_EXTENSIONS, &nbExtensions);

    for(i = 0; i < nbExtensions; i++)

    {

        const GLubyte *strExtension = glGetStringi(GL_EXTENSIONS, i);

        if(strcmp((const char *) strExtension, name) == 0)

            return 1;

    }

    return 0;

}

static int check_tfp_extensions(VADriverContextP ctx)

{

    const char *gl_extensions;

    const char *glx_extensions;

    gl_extensions = (const char *)glGetString(GL_EXTENSIONS);

    if (!check_extension("GL_ARB_texture_non_power_of_two", gl_extensions) && !check_extension3("GL_ARB_texture_non_power_of_two"))

        return 0;

    glx_extensions = glXQueryExtensionsString(ctx->native_dpy, ctx->x11_screen);

    if (!check_extension("GLX_EXT_texture_from_pixmap", glx_extensions))

        return 0;

    return 1;

}

static int check_fbo_extensions(VADriverContextP ctx)

{

    const char *gl_extensions;

    gl_extensions = (const char *)glGetString(GL_EXTENSIONS);

    if (check_extension("GL_ARB_framebuffer_object", gl_extensions) || check_extension3("GL_ARB_framebuffer_object"))

        return 1;

    if (check_extension("GL_EXT_framebuffer_object", gl_extensions) || check_extension3("GL_EXT_framebuffer_object"))

        return 1;

    return 0;

}

// Load GLX extensions

static int load_tfp_extensions(VADriverContextP ctx)

{

    VAOpenGLVTableP pOpenGLVTable = gl_get_vtable(ctx);

    pOpenGLVTable->glx_create_pixmap = (PFNGLXCREATEPIXMAPPROC)

        get_proc_address("glXCreatePixmap");

    if (!pOpenGLVTable->glx_create_pixmap)

        return 0;

    pOpenGLVTable->glx_destroy_pixmap = (PFNGLXDESTROYPIXMAPPROC)

        get_proc_address("glXDestroyPixmap");

    if (!pOpenGLVTable->glx_destroy_pixmap)

        return 0;

    pOpenGLVTable->glx_bind_tex_image = (PFNGLXBINDTEXIMAGEEXTPROC)

        get_proc_address("glXBindTexImageEXT");

    if (!pOpenGLVTable->glx_bind_tex_image)

        return 0;

    pOpenGLVTable->glx_release_tex_image = (PFNGLXRELEASETEXIMAGEEXTPROC)

        get_proc_address("glXReleaseTexImageEXT");

    if (!pOpenGLVTable->glx_release_tex_image)

        return 0;

    return 1;

}

static int load_fbo_extensions(VADriverContextP ctx)

{

    VAOpenGLVTableP pOpenGLVTable = gl_get_vtable(ctx);

    pOpenGLVTable->gl_gen_framebuffers = (PFNGLGENFRAMEBUFFERSEXTPROC)

        get_proc_address("glGenFramebuffersEXT");

    if (!pOpenGLVTable->gl_gen_framebuffers)

        return 0;

    pOpenGLVTable->gl_delete_framebuffers = (PFNGLDELETEFRAMEBUFFERSEXTPROC)

        get_proc_address("glDeleteFramebuffersEXT");

    if (!pOpenGLVTable->gl_delete_framebuffers)

        return 0;

    pOpenGLVTable->gl_bind_framebuffer = (PFNGLBINDFRAMEBUFFEREXTPROC)

        get_proc_address("glBindFramebufferEXT");

    if (!pOpenGLVTable->gl_bind_framebuffer)

        return 0;

    pOpenGLVTable->gl_gen_renderbuffers = (PFNGLGENRENDERBUFFERSEXTPROC)

        get_proc_address("glGenRenderbuffersEXT");

    if (!pOpenGLVTable->gl_gen_renderbuffers)

        return 0;

    pOpenGLVTable->gl_delete_renderbuffers = (PFNGLDELETERENDERBUFFERSEXTPROC)

        get_proc_address("glDeleteRenderbuffersEXT");

    if (!pOpenGLVTable->gl_delete_renderbuffers)

        return 0;

    pOpenGLVTable->gl_bind_renderbuffer = (PFNGLBINDRENDERBUFFEREXTPROC)

        get_proc_address("glBindRenderbufferEXT");

    if (!pOpenGLVTable->gl_bind_renderbuffer)

        return 0;

    pOpenGLVTable->gl_renderbuffer_storage = (PFNGLRENDERBUFFERSTORAGEEXTPROC)

        get_proc_address("glRenderbufferStorageEXT");

    if (!pOpenGLVTable->gl_renderbuffer_storage)

        return 0;

    pOpenGLVTable->gl_framebuffer_renderbuffer = (PFNGLFRAMEBUFFERRENDERBUFFEREXTPROC)

        get_proc_address("glFramebufferRenderbufferEXT");

    if (!pOpenGLVTable->gl_framebuffer_renderbuffer)

        return 0;

    pOpenGLVTable->gl_framebuffer_texture_2d = (PFNGLFRAMEBUFFERTEXTURE2DEXTPROC)

        get_proc_address("glFramebufferTexture2DEXT");

    if (!pOpenGLVTable->gl_framebuffer_texture_2d)

        return 0;

    pOpenGLVTable->gl_check_framebuffer_status = (PFNGLCHECKFRAMEBUFFERSTATUSEXTPROC)

        get_proc_address("glCheckFramebufferStatusEXT");

    if (!pOpenGLVTable->gl_check_framebuffer_status)

        return 0;

    return 1;

}

/* ========================================================================= */

/* === VA/GLX helpers                                                    === */

/* ========================================================================= */

// OpenGL context state

typedef struct OpenGLContextState *OpenGLContextStateP;

struct OpenGLContextState {

    Display     *display;

    Window       window;

    GLXContext   context;

};

static void

gl_destroy_context(OpenGLContextStateP cs)

{

    if (!cs)

        return;

    if (cs->display && cs->context) {

        if (glXGetCurrentContext() == cs->context)

            glXMakeCurrent(cs->display, None, NULL);

        glXDestroyContext(cs->display, cs->context);

        cs->display = NULL;

        cs->context = NULL;

    }

    free(cs);

}

static OpenGLContextStateP

gl_create_context(VADriverContextP ctx, OpenGLContextStateP parent)

{

    OpenGLContextStateP cs;

    GLXFBConfig *fbconfigs = NULL;

    int fbconfig_id, val, n, n_fbconfigs;

    Status status;

    static GLint fbconfig_attrs[] = {

        GLX_DRAWABLE_TYPE, GLX_WINDOW_BIT,

        GLX_RENDER_TYPE,   GLX_RGBA_BIT,

        GLX_DOUBLEBUFFER,  True,

        GLX_RED_SIZE,      8,

        GLX_GREEN_SIZE,    8, 

        GLX_BLUE_SIZE,     8,

        None

    };

    cs = malloc(sizeof(*cs));

    if (!cs)

        goto error;

    if (parent) {

        cs->display = parent->display;

        cs->window  = parent->window;

    }

    else {

        cs->display = ctx->native_dpy;

        cs->window  = None;

    }

    cs->context = NULL;

    if (parent && parent->context) {

        status = glXQueryContext(

            parent->display,

            parent->context,

            GLX_FBCONFIG_ID, &fbconfig_id

        );

        if (status != Success)

            goto error;

        if (fbconfig_id == GLX_DONT_CARE)

            goto choose_fbconfig;

        fbconfigs = glXGetFBConfigs(

            parent->display,

            DefaultScreen(parent->display),

            &n_fbconfigs

        );

        if (!fbconfigs)

            goto error;

        /* Find out a GLXFBConfig compatible with the parent context */

        for (n = 0; n < n_fbconfigs; n++) {

            status = glXGetFBConfigAttrib(

                cs->display,

                fbconfigs[n],

                GLX_FBCONFIG_ID, &val

            );

            if (status == Success && val == fbconfig_id)

                break;

        }

        if (n == n_fbconfigs)

            goto error;

    }

    else {

    choose_fbconfig:

        fbconfigs = glXChooseFBConfig(

            ctx->native_dpy,

            ctx->x11_screen,

            fbconfig_attrs, &n_fbconfigs

        );

        if (!fbconfigs)

            goto error;

        /* Select the first one */

        n = 0;

    }

    cs->context = glXCreateNewContext(

        cs->display,

        fbconfigs[n],

        GLX_RGBA_TYPE,

        parent ? parent->context : NULL,

        True

    );

    if (cs->context)

        goto end;

error:

    gl_destroy_context(cs);

    cs = NULL;

end:

    if (fbconfigs)

        XFree(fbconfigs);

    return cs;

}

static void gl_get_current_context(OpenGLContextStateP cs)

{

    cs->display = glXGetCurrentDisplay();

    cs->window  = glXGetCurrentDrawable();

    cs->context = glXGetCurrentContext();

}

static int

gl_set_current_context(OpenGLContextStateP new_cs, OpenGLContextStateP old_cs)

{

    /* If display is NULL, this could be that new_cs was retrieved from

       gl_get_current_context() with none set previously. If that case,

       the other fields are also NULL and we don't return an error */

    if (!new_cs->display)

        return !new_cs->window && !new_cs->context;

    if (old_cs) {

        if (old_cs == new_cs)

            return 1;

        gl_get_current_context(old_cs);

        if (old_cs->display == new_cs->display &&

            old_cs->window  == new_cs->window  &&

            old_cs->context == new_cs->context)

            return 1;

    }

    return glXMakeCurrent(new_cs->display, new_cs->window, new_cs->context);

}

/** Unique VASurfaceGLX identifier */

#define VA_SURFACE_GLX_MAGIC VA_FOURCC('V','A','G','L')

struct VASurfaceGLX {

    uint32_t            magic;      ///< Magic number identifying a VASurfaceGLX

    GLenum              target;     ///< GL target to which the texture is bound

    GLuint              texture;    ///< GL texture

    VASurfaceID         surface;    ///< Associated VA surface

    unsigned int        width;

    unsigned int        height;

    OpenGLContextStateP gl_context;

    int                 is_bound;

    Pixmap              pixmap;

    GLuint              pix_texture;

    GLXPixmap           glx_pixmap;

    GLuint              fbo;

};

// Create Pixmaps for GLX texture-from-pixmap extension

static int create_tfp_surface(VADriverContextP ctx, VASurfaceGLXP pSurfaceGLX)

{

    VAOpenGLVTableP const pOpenGLVTable = gl_get_vtable(ctx);

    const unsigned int    width         = pSurfaceGLX->width;

    const unsigned int    height        = pSurfaceGLX->height;

    Pixmap                pixmap        = None;

    GLXFBConfig          *fbconfig      = NULL;

    GLXPixmap             glx_pixmap    = None;

    Window                root_window;

    XWindowAttributes     wattr;

    int                  *attrib;

    int                   n_fbconfig_attrs;

    root_window = RootWindow(ctx->native_dpy, ctx->x11_screen);

    XGetWindowAttributes(ctx->native_dpy, root_window, &wattr);

    if (wattr.depth != 24 && wattr.depth != 32)

        return 0;

    pixmap = XCreatePixmap(

        ctx->native_dpy,

        root_window,

        width,

        height,

        wattr.depth

    );

    if (!pixmap)

        return 0;

    pSurfaceGLX->pixmap = pixmap;

    int fbconfig_attrs[32] = {

        GLX_DRAWABLE_TYPE,      GLX_PIXMAP_BIT,

        GLX_DOUBLEBUFFER,       GL_TRUE,

        GLX_RENDER_TYPE,        GLX_RGBA_BIT,

        GLX_X_RENDERABLE,       GL_TRUE,

        GLX_Y_INVERTED_EXT,     GL_TRUE,

        GLX_RED_SIZE,           8,

        GLX_GREEN_SIZE,         8,

        GLX_BLUE_SIZE,          8,

        /*

         * depth test isn't enabled in the implementaion of VA GLX,

         * so depth buffer is unnecessary. However to workaround a

         * bug in older verson of xorg-server, always require a depth

         * buffer.

         *

         * See https://bugs.freedesktop.org/show_bug.cgi?id=76755

         */

        GLX_DEPTH_SIZE,         1,

        GL_NONE,

    };

    for (attrib = fbconfig_attrs; *attrib != GL_NONE; attrib += 2)

        ;

    if (wattr.depth == 32) {

    *attrib++ = GLX_ALPHA_SIZE;                 *attrib++ = 8;

    *attrib++ = GLX_BIND_TO_TEXTURE_RGBA_EXT;   *attrib++ = GL_TRUE;

    }

    else {

    *attrib++ = GLX_BIND_TO_TEXTURE_RGB_EXT;    *attrib++ = GL_TRUE;

    }

    *attrib++ = GL_NONE;

    fbconfig = glXChooseFBConfig(

        ctx->native_dpy,

        ctx->x11_screen,

        fbconfig_attrs,

        &n_fbconfig_attrs

    );

    if (!fbconfig)

        return 0;

    int pixmap_attrs[10] = {

        GLX_TEXTURE_TARGET_EXT, GLX_TEXTURE_2D_EXT,

        GLX_MIPMAP_TEXTURE_EXT, GL_FALSE,

        GL_NONE,

    };

    for (attrib = pixmap_attrs; *attrib != GL_NONE; attrib += 2)

        ;

    *attrib++ = GLX_TEXTURE_FORMAT_EXT;

    if (wattr.depth == 32)

    *attrib++ = GLX_TEXTURE_FORMAT_RGBA_EXT;

    else

    *attrib++ = GLX_TEXTURE_FORMAT_RGB_EXT;

    *attrib++ = GL_NONE;

    x11_trap_errors();

    glx_pixmap = pOpenGLVTable->glx_create_pixmap(

        ctx->native_dpy,

        fbconfig[0],

        pixmap,

        pixmap_attrs

    );

    free(fbconfig);

    if (x11_untrap_errors() != 0)

        return 0;

    pSurfaceGLX->glx_pixmap = glx_pixmap;

    glGenTextures(1, &pSurfaceGLX->pix_texture);

    glBindTexture(GL_TEXTURE_2D, pSurfaceGLX->pix_texture);

    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);

    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);

    return 1;

}

// Destroy Pixmaps used for TFP

static void destroy_tfp_surface(VADriverContextP ctx, VASurfaceGLXP pSurfaceGLX)

{

    VAOpenGLVTableP const pOpenGLVTable = gl_get_vtable(ctx);

    if (pSurfaceGLX->pix_texture) {

        glDeleteTextures(1, &pSurfaceGLX->pix_texture);

        pSurfaceGLX->pix_texture = 0;

    }

    if (pSurfaceGLX->glx_pixmap) {

        pOpenGLVTable->glx_destroy_pixmap(ctx->native_dpy, pSurfaceGLX->glx_pixmap);

        pSurfaceGLX->glx_pixmap = None;

    }

    if (pSurfaceGLX->pixmap) {

        XFreePixmap(ctx->native_dpy, pSurfaceGLX->pixmap);

        pSurfaceGLX->pixmap = None;

    }

}

// Bind GLX Pixmap to texture

static int bind_pixmap(VADriverContextP ctx, VASurfaceGLXP pSurfaceGLX)

{

    VAOpenGLVTableP pOpenGLVTable = gl_get_vtable(ctx);

    if (pSurfaceGLX->is_bound)

        return 1;

    glBindTexture(GL_TEXTURE_2D, pSurfaceGLX->pix_texture);

    x11_trap_errors();

    pOpenGLVTable->glx_bind_tex_image(

        ctx->native_dpy,

        pSurfaceGLX->glx_pixmap,

        GLX_FRONT_LEFT_EXT,

        NULL

    );

    XSync(ctx->native_dpy, False);

    if (x11_untrap_errors() != 0) {

        va_glx_error_message("failed to bind pixmap\n");

        return 0;

    }

    pSurfaceGLX->is_bound = 1;

    return 1;

}

// Release GLX Pixmap from texture

static int unbind_pixmap(VADriverContextP ctx, VASurfaceGLXP pSurfaceGLX)

{

    VAOpenGLVTableP pOpenGLVTable = gl_get_vtable(ctx);

    if (!pSurfaceGLX->is_bound)

        return 1;

    x11_trap_errors();

    pOpenGLVTable->glx_release_tex_image(

        ctx->native_dpy,

        pSurfaceGLX->glx_pixmap,

        GLX_FRONT_LEFT_EXT

    );

    XSync(ctx->native_dpy, False);

    if (x11_untrap_errors() != 0) {

        va_glx_error_message("failed to release pixmap\n");

        return 0;

    }

    glBindTexture(GL_TEXTURE_2D, 0);

    pSurfaceGLX->is_bound = 0;

    return 1;

}

// Render GLX Pixmap to texture

static void render_pixmap(VADriverContextP ctx, VASurfaceGLXP pSurfaceGLX)

{

    const unsigned int w = pSurfaceGLX->width;

    const unsigned int h = pSurfaceGLX->height;

    glColor4f(1.0f, 1.0f, 1.0f, 1.0f);

    glBegin(GL_QUADS);

    {

        glTexCoord2f(0.0f, 0.0f); glVertex2i(0, 0);

        glTexCoord2f(0.0f, 1.0f); glVertex2i(0, h);

        glTexCoord2f(1.0f, 1.0f); glVertex2i(w, h);

        glTexCoord2f(1.0f, 0.0f); glVertex2i(w, 0);

    }

    glEnd();

}

// Create offscreen surface

static int create_fbo_surface(VADriverContextP ctx, VASurfaceGLXP pSurfaceGLX)

{

    VAOpenGLVTableP pOpenGLVTable = gl_get_vtable(ctx);

    GLuint fbo;

    GLenum status;

    pOpenGLVTable->gl_gen_framebuffers(1, &fbo);

    pOpenGLVTable->gl_bind_framebuffer(GL_FRAMEBUFFER_EXT, fbo);

    pOpenGLVTable->gl_framebuffer_texture_2d(

        GL_FRAMEBUFFER_EXT,

        GL_COLOR_ATTACHMENT0_EXT,

        GL_TEXTURE_2D,

        pSurfaceGLX->texture,

        0

    );

    status = pOpenGLVTable->gl_check_framebuffer_status(GL_DRAW_FRAMEBUFFER_EXT);

    pOpenGLVTable->gl_bind_framebuffer(GL_FRAMEBUFFER_EXT, 0);

    if (status != GL_FRAMEBUFFER_COMPLETE_EXT)

        return 0;

    pSurfaceGLX->fbo = fbo;

    return 1;

}

// Destroy offscreen surface

static void destroy_fbo_surface(VADriverContextP ctx, VASurfaceGLXP pSurfaceGLX)

{

    VAOpenGLVTableP pOpenGLVTable = gl_get_vtable(ctx);

    if (pSurfaceGLX->fbo) {

        pOpenGLVTable->gl_delete_framebuffers(1, &pSurfaceGLX->fbo);

        pSurfaceGLX->fbo = 0;

    }

}

// Setup matrices to match the FBO texture dimensions

static void fbo_enter(VADriverContextP ctx, VASurfaceGLXP pSurfaceGLX)

{

    VAOpenGLVTableP pOpenGLVTable = gl_get_vtable(ctx);

    const unsigned int width  = pSurfaceGLX->width;

    const unsigned int height = pSurfaceGLX->height;

    pOpenGLVTable->gl_bind_framebuffer(GL_FRAMEBUFFER_EXT, pSurfaceGLX->fbo);

    glPushAttrib(GL_VIEWPORT_BIT);

    glMatrixMode(GL_PROJECTION);

    glPushMatrix();

    glLoadIdentity();

    glMatrixMode(GL_MODELVIEW);

    glPushMatrix();

    glLoadIdentity();

    glViewport(0, 0, width, height);

    glTranslatef(-1.0f, -1.0f, 0.0f);

    glScalef(2.0f / width, 2.0f / height, 1.0f);

}

// Restore original OpenGL matrices

static void fbo_leave(VADriverContextP ctx)

{

    VAOpenGLVTableP pOpenGLVTable = gl_get_vtable(ctx);

    glPopAttrib();

    glMatrixMode(GL_PROJECTION);

    glPopMatrix();

    glMatrixMode(GL_MODELVIEW);

    glPopMatrix();

    pOpenGLVTable->gl_bind_framebuffer(GL_FRAMEBUFFER_EXT, 0);

}

// Check internal texture format is supported

static int is_supported_internal_format(GLenum format)

{

    /* XXX: we don't support other textures than RGBA */

    switch (format) {

    case 4:

    case GL_RGBA:

    case GL_RGBA8:

        return 1;

    }

    return 0;

}

// Destroy VA/GLX surface

static void

destroy_surface(VADriverContextP ctx, VASurfaceGLXP pSurfaceGLX)

{

    unbind_pixmap(ctx, pSurfaceGLX);

    destroy_fbo_surface(ctx, pSurfaceGLX);

    destroy_tfp_surface(ctx, pSurfaceGLX);

    free(pSurfaceGLX);

}

// Create VA/GLX surface

static VASurfaceGLXP

create_surface(VADriverContextP ctx, GLenum target, GLuint texture)

{

    VASurfaceGLXP pSurfaceGLX = NULL;

    unsigned int internal_format, border_width, width, height;

    int is_error = 1;

    pSurfaceGLX = malloc(sizeof(*pSurfaceGLX));

    if (!pSurfaceGLX)

        goto end;

    pSurfaceGLX->magic          = VA_SURFACE_GLX_MAGIC;

    pSurfaceGLX->target         = target;

    pSurfaceGLX->texture        = texture;

    pSurfaceGLX->surface        = VA_INVALID_SURFACE;

    pSurfaceGLX->gl_context     = NULL;

    pSurfaceGLX->is_bound       = 0;

    pSurfaceGLX->pixmap         = None;

    pSurfaceGLX->pix_texture    = 0;

    pSurfaceGLX->glx_pixmap     = None;

    pSurfaceGLX->fbo            = 0;

    glEnable(target);

    glBindTexture(target, texture);

    if (!gl_get_texture_param(GL_TEXTURE_INTERNAL_FORMAT, &internal_format))

        goto end;

    if (!is_supported_internal_format(internal_format))

        goto end;

    /* Check texture dimensions */

    if (!gl_get_texture_param(GL_TEXTURE_BORDER, &border_width))

        goto end;

    if (!gl_get_texture_param(GL_TEXTURE_WIDTH, &width))

        goto end;

    if (!gl_get_texture_param(GL_TEXTURE_HEIGHT, &height))

        goto end;

    width  -= 2 * border_width;

    height -= 2 * border_width;

    if (width == 0 || height == 0)

        goto end;

    pSurfaceGLX->width  = width;

    pSurfaceGLX->height = height;

    /* Create TFP objects */

    if (!create_tfp_surface(ctx, pSurfaceGLX))

        goto end;

    /* Create FBO objects */

    if (!create_fbo_surface(ctx, pSurfaceGLX))

        goto end;

    is_error = 0;

end:

    if (is_error && pSurfaceGLX) {

        destroy_surface(ctx, pSurfaceGLX);

        pSurfaceGLX = NULL;

    }

    return pSurfaceGLX;

}

/* ========================================================================= */

/* === VA/GLX implementation from the driver (fordward calls)            === */

/* ========================================================================= */

#define INVOKE(ctx, func, args) do {                    \

        VADriverVTableGLXP vtable = (ctx)->vtable_glx;  \

        if (!vtable->va##func##GLX)                     \

            return VA_STATUS_ERROR_UNIMPLEMENTED;       \

                                                        \

        VAStatus status = vtable->va##func##GLX args;   \

        if (status != VA_STATUS_SUCCESS)                \

            return status;                              \

    } while (0)

static VAStatus

vaCreateSurfaceGLX_impl_driver(

    VADriverContextP    ctx,

    GLenum              target,

    GLuint              texture,

    void              **gl_surface

)

{

    INVOKE(ctx, CreateSurface, (ctx, target, texture, gl_surface));

    return VA_STATUS_SUCCESS;

}

static VAStatus

vaDestroySurfaceGLX_impl_driver(VADriverContextP ctx, void *gl_surface)

{

    INVOKE(ctx, DestroySurface, (ctx, gl_surface));

    return VA_STATUS_SUCCESS;

}

static VAStatus

vaCopySurfaceGLX_impl_driver(

    VADriverContextP    ctx,

    void               *gl_surface,

    VASurfaceID         surface,

    unsigned int        flags

)

{

    INVOKE(ctx, CopySurface, (ctx, gl_surface, surface, flags));