view src/video/SDL_video.c @ 5172:ededa1ccf91c

Switched the SDL 1.2 compatibility to use the window surface, so it's fast even when there's no hardware acceleration available. This means that the YUV overlay now uses software, but that's okay since fast YUV code should be using the textures now anyway.
author Sam Lantinga <slouken@libsdl.org>
date Thu, 03 Feb 2011 21:13:55 -0800
parents db487f28419e
children 51b4cfdf7ebb
line wrap: on
line source

/*
    SDL - Simple DirectMedia Layer
    Copyright (C) 1997-2010 Sam Lantinga

    This library is free software; you can redistribute it and/or
    modify it under the terms of the GNU Lesser General Public
    License as published by the Free Software Foundation; either
    version 2.1 of the License, or (at your option) any later version.

    This library is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
    Lesser General Public License for more details.

    You should have received a copy of the GNU Lesser General Public
    License along with this library; if not, write to the Free Software
    Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA

    Sam Lantinga
    slouken@libsdl.org
*/
#include "SDL_config.h"

/* The high-level video driver subsystem */

#include "SDL.h"
#include "SDL_video.h"
#include "SDL_sysvideo.h"
#include "SDL_blit.h"
#include "SDL_pixels_c.h"
#include "../events/SDL_events_c.h"

#if SDL_VIDEO_OPENGL_ES
#include "SDL_opengles.h"
#endif /* SDL_VIDEO_OPENGL_ES */

#if SDL_VIDEO_OPENGL
#include "SDL_opengl.h"
#endif /* SDL_VIDEO_OPENGL */

#include "SDL_syswm.h"

/* On Windows, windows.h defines CreateWindow */
#ifdef CreateWindow
#undef CreateWindow
#endif

/* Available video drivers */
static VideoBootStrap *bootstrap[] = {
#if SDL_VIDEO_DRIVER_COCOA
    &COCOA_bootstrap,
#endif
#if SDL_VIDEO_DRIVER_X11
    &X11_bootstrap,
#endif
#if SDL_VIDEO_DRIVER_DIRECTFB
    &DirectFB_bootstrap,
#endif
#if SDL_VIDEO_DRIVER_WINDOWS
    &WINDOWS_bootstrap,
#endif
#if SDL_VIDEO_DRIVER_BWINDOW
    &BWINDOW_bootstrap,
#endif
#if SDL_VIDEO_DRIVER_PANDORA
    &PND_bootstrap,
#endif
#if SDL_VIDEO_DRIVER_NDS
    &NDS_bootstrap,
#endif
#if SDL_VIDEO_DRIVER_UIKIT
    &UIKIT_bootstrap,
#endif
#if SDL_VIDEO_DRIVER_ANDROID
    &Android_bootstrap,
#endif
#if SDL_VIDEO_DRIVER_DUMMY
    &DUMMY_bootstrap,
#endif
    NULL
};

static SDL_VideoDevice *_this = NULL;

#define CHECK_WINDOW_MAGIC(window, retval) \
    if (!_this) { \
        SDL_UninitializedVideo(); \
        return retval; \
    } \
    if (!window || window->magic != &_this->window_magic) { \
        SDL_SetError("Invalid window"); \
        return retval; \
    }

/* Various local functions */
static void SDL_UpdateWindowGrab(SDL_Window * window);

/* Support for framebuffer emulation using an accelerated renderer */

#define SDL_WINDOWTEXTUREDATA   "_SDL_WindowTextureData"

typedef struct {
    SDL_Renderer *renderer;
    SDL_Texture *texture;
    void *pixels;
    int pitch;
} SDL_WindowTextureData;

static int
SDL_CreateWindowTexture(_THIS, SDL_Window * window, Uint32 * format, void ** pixels, int *pitch)
{
    SDL_WindowTextureData *data;
    SDL_Renderer *renderer;
    SDL_RendererInfo info;
    Uint32 i;

    data = SDL_GetWindowData(window, SDL_WINDOWTEXTUREDATA);
    if (!data) {
        data = (SDL_WindowTextureData *)SDL_calloc(1, sizeof(*data));
        if (!data) {
            SDL_OutOfMemory();
            return -1;
        }
        SDL_SetWindowData(window, SDL_WINDOWTEXTUREDATA, data);
    }

    renderer = data->renderer;
    if (!renderer) {
        SDL_RendererInfo info;
        int i;

        /* We need to make sure we don't get a software renderer */
        for (i = 0; i < SDL_GetNumRenderDrivers(); ++i) {
            SDL_GetRenderDriverInfo(i, &info);
            if (SDL_strcmp(info.name, "software") != 0) {
                renderer = SDL_CreateRenderer(window, i, 0);
                if (renderer) {
                    break;
                }
            }
        }
        if (!renderer) {
            return -1;
        }
        data->renderer = renderer;
    }

    /* Free any old texture and pixel data */
    if (data->texture) {
        SDL_DestroyTexture(data->texture);
        data->texture = NULL;
    }
    if (data->pixels) {
        SDL_free(data->pixels);
        data->pixels = NULL;
    }

    if (SDL_GetRendererInfo(renderer, &info) < 0) {
        return -1;
    }

    /* Find the first format without an alpha channel */
    *format = info.texture_formats[0];
    for (i = 0; i < info.num_texture_formats; ++i) {
        if (!SDL_ISPIXELFORMAT_ALPHA(info.texture_formats[i])) {
            *format = info.texture_formats[i];
            break;
        }
    }

    data->texture = SDL_CreateTexture(renderer, *format,
                                      SDL_TEXTUREACCESS_STREAMING,
                                      window->w, window->h);
    if (!data->texture) {
        return -1;
    }

    /* Create framebuffer data */
    data->pitch = (((window->w * SDL_BYTESPERPIXEL(*format)) + 3) & ~3);
    data->pixels = SDL_malloc(window->h * data->pitch);
    if (!data->pixels) {
        SDL_OutOfMemory();
        return -1;
    }

    *pixels = data->pixels;
    *pitch = data->pitch;
    return 0;
}

static int
SDL_UpdateWindowTexture(_THIS, SDL_Window * window, int numrects, SDL_Rect * rects)
{
    SDL_WindowTextureData *data;

    data = SDL_GetWindowData(window, SDL_WINDOWTEXTUREDATA);
    if (!data || !data->texture) {
        SDL_SetError("No window texture data");
        return -1;
    }

    if (SDL_UpdateTexture(data->texture, NULL, data->pixels, data->pitch) < 0) {
        return -1;
    }
    if (SDL_RenderCopy(data->renderer, data->texture, NULL, NULL) < 0) {
        return -1;
    }
    SDL_RenderPresent(data->renderer);
    return 0;
}

static void
SDL_DestroyWindowTexture(_THIS, SDL_Window * window)
{
    SDL_WindowTextureData *data;

    data = SDL_SetWindowData(window, SDL_WINDOWTEXTUREDATA, NULL);
    if (!data) {
        return;
    }
    if (data->texture) {
        SDL_DestroyTexture(data->texture);
    }
    if (data->renderer) {
        SDL_DestroyRenderer(data->renderer);
    }
    if (data->pixels) {
        SDL_free(data->pixels);
    }
    SDL_free(data);
}


static int
cmpmodes(const void *A, const void *B)
{
    SDL_DisplayMode a = *(const SDL_DisplayMode *) A;
    SDL_DisplayMode b = *(const SDL_DisplayMode *) B;

    if (a.w != b.w) {
        return b.w - a.w;
    }
    if (a.h != b.h) {
        return b.h - a.h;
    }
    if (SDL_BITSPERPIXEL(a.format) != SDL_BITSPERPIXEL(b.format)) {
        return SDL_BITSPERPIXEL(b.format) - SDL_BITSPERPIXEL(a.format);
    }
    if (SDL_PIXELLAYOUT(a.format) != SDL_PIXELLAYOUT(b.format)) {
        return SDL_PIXELLAYOUT(b.format) - SDL_PIXELLAYOUT(a.format);
    }
    if (a.refresh_rate != b.refresh_rate) {
        return b.refresh_rate - a.refresh_rate;
    }
    return 0;
}

static void
SDL_UninitializedVideo()
{
    SDL_SetError("Video subsystem has not been initialized");
}

int
SDL_GetNumVideoDrivers(void)
{
    return SDL_arraysize(bootstrap) - 1;
}

const char *
SDL_GetVideoDriver(int index)
{
    if (index >= 0 && index < SDL_GetNumVideoDrivers()) {
        return bootstrap[index]->name;
    }
    return NULL;
}

/*
 * Initialize the video and event subsystems -- determine native pixel format
 */
int
SDL_VideoInit(const char *driver_name)
{
    SDL_VideoDevice *video;
    int index;
    int i;

    /* Check to make sure we don't overwrite '_this' */
    if (_this != NULL) {
        SDL_VideoQuit();
    }

    /* Start the event loop */
    if (SDL_StartEventLoop() < 0 ||
        SDL_KeyboardInit() < 0 ||
        SDL_MouseInit() < 0 ||
        SDL_TouchInit() < 0 ||
        SDL_QuitInit() < 0) {
        return -1;
    }

    /* Select the proper video driver */
    index = 0;
    video = NULL;
    if (driver_name == NULL) {
        driver_name = SDL_getenv("SDL_VIDEODRIVER");
    }
    if (driver_name != NULL) {
        for (i = 0; bootstrap[i]; ++i) {
            if (SDL_strcasecmp(bootstrap[i]->name, driver_name) == 0) {
                video = bootstrap[i]->create(index);
                break;
            }
        }
    } else {
        for (i = 0; bootstrap[i]; ++i) {
            if (bootstrap[i]->available()) {
                video = bootstrap[i]->create(index);
                if (video != NULL) {
                    break;
                }
            }
        }
    }
    if (video == NULL) {
        if (driver_name) {
            SDL_SetError("%s not available", driver_name);
        } else {
            SDL_SetError("No available video device");
        }
        return -1;
    }
    _this = video;
    _this->name = bootstrap[i]->name;
    _this->next_object_id = 1;


    /* Set some very sane GL defaults */
    _this->gl_config.driver_loaded = 0;
    _this->gl_config.dll_handle = NULL;
    _this->gl_config.red_size = 3;
    _this->gl_config.green_size = 3;
    _this->gl_config.blue_size = 2;
    _this->gl_config.alpha_size = 0;
    _this->gl_config.buffer_size = 0;
    _this->gl_config.depth_size = 16;
    _this->gl_config.stencil_size = 0;
    _this->gl_config.double_buffer = 1;
    _this->gl_config.accum_red_size = 0;
    _this->gl_config.accum_green_size = 0;
    _this->gl_config.accum_blue_size = 0;
    _this->gl_config.accum_alpha_size = 0;
    _this->gl_config.stereo = 0;
    _this->gl_config.multisamplebuffers = 0;
    _this->gl_config.multisamplesamples = 0;
    _this->gl_config.retained_backing = 1;
    _this->gl_config.accelerated = -1;  /* accelerated or not, both are fine */
    _this->gl_config.major_version = 2;
    _this->gl_config.minor_version = 1;

    /* Initialize the video subsystem */
    if (_this->VideoInit(_this) < 0) {
        SDL_VideoQuit();
        return -1;
    }

    /* Make sure some displays were added */
    if (_this->num_displays == 0) {
        SDL_SetError("The video driver did not add any displays");
        SDL_VideoQuit();
        return (-1);
    }

    /* Add the renderer framebuffer emulation if needed */
    if (!_this->CreateWindowFramebuffer) {
        _this->CreateWindowFramebuffer = SDL_CreateWindowTexture;
        _this->UpdateWindowFramebuffer = SDL_UpdateWindowTexture;
        _this->DestroyWindowFramebuffer = SDL_DestroyWindowTexture;
    }

    /* We're ready to go! */
    return 0;
}

const char *
SDL_GetCurrentVideoDriver()
{
    if (!_this) {
        SDL_UninitializedVideo();
        return NULL;
    }
    return _this->name;
}

SDL_VideoDevice *
SDL_GetVideoDevice(void)
{
    return _this;
}

int
SDL_AddBasicVideoDisplay(const SDL_DisplayMode * desktop_mode)
{
    SDL_VideoDisplay display;

    SDL_zero(display);
    if (desktop_mode) {
        display.desktop_mode = *desktop_mode;
    }
    display.current_mode = display.desktop_mode;

    return SDL_AddVideoDisplay(&display);
}

int
SDL_AddVideoDisplay(const SDL_VideoDisplay * display)
{
    SDL_VideoDisplay *displays;
    int index = -1;

    displays =
        SDL_realloc(_this->displays,
                    (_this->num_displays + 1) * sizeof(*displays));
    if (displays) {
        index = _this->num_displays++;
        displays[index] = *display;
        displays[index].device = _this;
        _this->displays = displays;
    } else {
        SDL_OutOfMemory();
    }
    return index;
}

int
SDL_GetNumVideoDisplays(void)
{
    if (!_this) {
        SDL_UninitializedVideo();
        return 0;
    }
    return _this->num_displays;
}

int
SDL_GetDisplayBounds(int index, SDL_Rect * rect)
{
    if (!_this) {
        SDL_UninitializedVideo();
        return -1;
    }
    if (index < 0 || index >= _this->num_displays) {
        SDL_SetError("index must be in the range 0 - %d",
                     _this->num_displays - 1);
        return -1;
    }
    if (rect) {
        SDL_VideoDisplay *display = &_this->displays[index];

        if (_this->GetDisplayBounds) {
            if (_this->GetDisplayBounds(_this, display, rect) < 0) {
                return -1;
            }
        } else {
            /* Assume that the displays are left to right */
            if (index == 0) {
                rect->x = 0;
                rect->y = 0;
            } else {
                SDL_GetDisplayBounds(index-1, rect);
                rect->x += rect->w;
            }
            rect->w = display->desktop_mode.w;
            rect->h = display->desktop_mode.h;
        }
    }
    return 0;
}

int
SDL_SelectVideoDisplay(int index)
{
    if (!_this) {
        SDL_UninitializedVideo();
        return (-1);
    }
    if (index < 0 || index >= _this->num_displays) {
        SDL_SetError("index must be in the range 0 - %d",
                     _this->num_displays - 1);
        return -1;
    }
    _this->current_display = index;
    return 0;
}

int
SDL_GetCurrentVideoDisplay(void)
{
    if (!_this) {
        SDL_UninitializedVideo();
        return (-1);
    }
    return _this->current_display;
}

SDL_bool
SDL_AddDisplayMode(SDL_VideoDisplay * display,  const SDL_DisplayMode * mode)
{
    SDL_DisplayMode *modes;
    int i, nmodes;

    /* Make sure we don't already have the mode in the list */
    modes = display->display_modes;
    nmodes = display->num_display_modes;
    for (i = nmodes; i--;) {
        if (SDL_memcmp(mode, &modes[i], sizeof(*mode)) == 0) {
            return SDL_FALSE;
        }
    }

    /* Go ahead and add the new mode */
    if (nmodes == display->max_display_modes) {
        modes =
            SDL_realloc(modes,
                        (display->max_display_modes + 32) * sizeof(*modes));
        if (!modes) {
            return SDL_FALSE;
        }
        display->display_modes = modes;
        display->max_display_modes += 32;
    }
    modes[nmodes] = *mode;
    display->num_display_modes++;

    /* Re-sort video modes */
    SDL_qsort(display->display_modes, display->num_display_modes,
              sizeof(SDL_DisplayMode), cmpmodes);

    return SDL_TRUE;
}

int
SDL_GetNumDisplayModesForDisplay(SDL_VideoDisplay * display)
{
    if (!display->num_display_modes && _this->GetDisplayModes) {
        _this->GetDisplayModes(_this, display);
        SDL_qsort(display->display_modes, display->num_display_modes,
                  sizeof(SDL_DisplayMode), cmpmodes);
    }
    return display->num_display_modes;
}

int
SDL_GetNumDisplayModes()
{
    if (_this) {
        return SDL_GetNumDisplayModesForDisplay(SDL_CurrentDisplay);
    }
    return 0;
}

int
SDL_GetDisplayModeForDisplay(SDL_VideoDisplay * display, int index, SDL_DisplayMode * mode)
{
    if (index < 0 || index >= SDL_GetNumDisplayModesForDisplay(display)) {
        SDL_SetError("index must be in the range of 0 - %d",
                     SDL_GetNumDisplayModesForDisplay(display) - 1);
        return -1;
    }
    if (mode) {
        *mode = display->display_modes[index];
    }
    return 0;
}

int
SDL_GetDisplayMode(int index, SDL_DisplayMode * mode)
{
    return SDL_GetDisplayModeForDisplay(SDL_CurrentDisplay, index, mode);
}

int
SDL_GetDesktopDisplayModeForDisplay(SDL_VideoDisplay * display, SDL_DisplayMode * mode)
{
    if (mode) {
        *mode = display->desktop_mode;
    }
    return 0;
}

int
SDL_GetDesktopDisplayMode(SDL_DisplayMode * mode)
{
    if (!_this) {
        SDL_UninitializedVideo();
        return -1;
    }
    return SDL_GetDesktopDisplayModeForDisplay(SDL_CurrentDisplay, mode);
}

int
SDL_GetCurrentDisplayModeForDisplay(SDL_VideoDisplay * display, SDL_DisplayMode * mode)
{
    if (mode) {
        *mode = display->current_mode;
    }
    return 0;
}

int
SDL_GetCurrentDisplayMode(SDL_DisplayMode * mode)
{
    if (!_this) {
        SDL_UninitializedVideo();
        return -1;
    }
    return SDL_GetCurrentDisplayModeForDisplay(SDL_CurrentDisplay, mode);
}

SDL_DisplayMode *
SDL_GetClosestDisplayModeForDisplay(SDL_VideoDisplay * display,
                                    const SDL_DisplayMode * mode,
                                    SDL_DisplayMode * closest)
{
    Uint32 target_format;
    int target_refresh_rate;
    int i;
    SDL_DisplayMode *current, *match;

    if (!mode || !closest) {
        SDL_SetError("Missing desired mode or closest mode parameter");
        return NULL;
    }

    /* Default to the desktop format */
    if (mode->format) {
        target_format = mode->format;
    } else {
        target_format = display->desktop_mode.format;
    }

    /* Default to the desktop refresh rate */
    if (mode->refresh_rate) {
        target_refresh_rate = mode->refresh_rate;
    } else {
        target_refresh_rate = display->desktop_mode.refresh_rate;
    }

    match = NULL;
    for (i = 0; i < SDL_GetNumDisplayModesForDisplay(display); ++i) {
        current = &display->display_modes[i];

        if (current->w && (current->w < mode->w)) {
            /* Out of sorted modes large enough here */
            break;
        }
        if (current->h && (current->h < mode->h)) {
            if (current->w && (current->w == mode->w)) {
                /* Out of sorted modes large enough here */
                break;
            }
            /* Wider, but not tall enough, due to a different
               aspect ratio. This mode must be skipped, but closer
               modes may still follow. */
            continue;
        }
        if (!match || current->w < match->w || current->h < match->h) {
            match = current;
            continue;
        }
        if (current->format != match->format) {
            /* Sorted highest depth to lowest */
            if (current->format == target_format ||
                (SDL_BITSPERPIXEL(current->format) >=
                 SDL_BITSPERPIXEL(target_format)
                 && SDL_PIXELTYPE(current->format) ==
                 SDL_PIXELTYPE(target_format))) {
                match = current;
            }
            continue;
        }
        if (current->refresh_rate != match->refresh_rate) {
            /* Sorted highest refresh to lowest */
            if (current->refresh_rate >= target_refresh_rate) {
                match = current;
            }
        }
    }
    if (match) {
        if (match->format) {
            closest->format = match->format;
        } else {
            closest->format = mode->format;
        }
        if (match->w && match->h) {
            closest->w = match->w;
            closest->h = match->h;
        } else {
            closest->w = mode->w;
            closest->h = mode->h;
        }
        if (match->refresh_rate) {
            closest->refresh_rate = match->refresh_rate;
        } else {
            closest->refresh_rate = mode->refresh_rate;
        }
        closest->driverdata = match->driverdata;

        /*
         * Pick some reasonable defaults if the app and driver don't
         * care
         */
        if (!closest->format) {
            closest->format = SDL_PIXELFORMAT_RGB888;
        }
        if (!closest->w) {
            closest->w = 640;
        }
        if (!closest->h) {
            closest->h = 480;
        }
        return closest;
    }
    return NULL;
}

SDL_DisplayMode *
SDL_GetClosestDisplayMode(const SDL_DisplayMode * mode,
                          SDL_DisplayMode * closest)
{
    if (!_this) {
        SDL_UninitializedVideo();
        return NULL;
    }
    return SDL_GetClosestDisplayModeForDisplay(SDL_CurrentDisplay, mode, closest);
}

int
SDL_SetDisplayModeForDisplay(SDL_VideoDisplay * display, const SDL_DisplayMode * mode)
{
    SDL_DisplayMode display_mode;
    SDL_DisplayMode current_mode;

    if (mode) {
        display_mode = *mode;

        /* Default to the current mode */
        if (!display_mode.format) {
            display_mode.format = display->current_mode.format;
        }
        if (!display_mode.w) {
            display_mode.w = display->current_mode.w;
        }
        if (!display_mode.h) {
            display_mode.h = display->current_mode.h;
        }
        if (!display_mode.refresh_rate) {
            display_mode.refresh_rate = display->current_mode.refresh_rate;
        }

        /* Get a good video mode, the closest one possible */
        if (!SDL_GetClosestDisplayModeForDisplay(display, &display_mode, &display_mode)) {
            SDL_SetError("No video mode large enough for %dx%d",
                         display_mode.w, display_mode.h);
            return -1;
        }
    } else {
        display_mode = display->desktop_mode;
    }

    /* See if there's anything left to do */
    SDL_GetCurrentDisplayModeForDisplay(display, &current_mode);
    if (SDL_memcmp(&display_mode, &current_mode, sizeof(display_mode)) == 0) {
        return 0;
    }

    /* Actually change the display mode */
    if (!_this->SetDisplayMode) {
        SDL_SetError("Video driver doesn't support changing display mode");
        return -1;
    }
    if (_this->SetDisplayMode(_this, display, &display_mode) < 0) {
        return -1;
    }
    display->current_mode = display_mode;
    return 0;
}

int
SDL_SetWindowDisplayMode(SDL_Window * window, const SDL_DisplayMode * mode)
{
    CHECK_WINDOW_MAGIC(window, -1);

    if (mode) {
        window->fullscreen_mode = *mode;
    } else {
        SDL_zero(window->fullscreen_mode);
    }
    return 0;
}

int
SDL_GetWindowDisplayMode(SDL_Window * window, SDL_DisplayMode * mode)
{
    SDL_DisplayMode fullscreen_mode;

    CHECK_WINDOW_MAGIC(window, -1);

    fullscreen_mode = window->fullscreen_mode;
    if (!fullscreen_mode.w) {
        fullscreen_mode.w = window->w;
    }
    if (!fullscreen_mode.h) {
        fullscreen_mode.h = window->h;
    }

    if (!SDL_GetClosestDisplayModeForDisplay(window->display,
                                             &fullscreen_mode,
                                             &fullscreen_mode)) {
        SDL_SetError("Couldn't find display mode match");
        return -1;
    }

    if (mode) {
        *mode = fullscreen_mode;
    }
    return 0;
}

Uint32
SDL_GetWindowPixelFormat(SDL_Window * window)
{
    SDL_VideoDisplay *display = window->display;
    SDL_DisplayMode *displayMode = &display->current_mode;
    return displayMode->format;
}

static void
SDL_UpdateFullscreenMode(SDL_Window * window, SDL_bool attempt)
{
    SDL_VideoDisplay *display = window->display;

    /* See if we're already processing a window */
    if (display->updating_fullscreen) {
        return;
    }

    display->updating_fullscreen = SDL_TRUE;

    /* See if we even want to do anything here */
    if ((window->flags & SDL_WINDOW_FULLSCREEN) &&
        (window->flags & SDL_WINDOW_SHOWN)) {
        if (attempt) {
            /* We just gained some state, try to gain all states */
            if (window->flags & SDL_WINDOW_MINIMIZED) {
                SDL_RestoreWindow(window);
            } else {
                SDL_RaiseWindow(window);
            }
        } else {
            /* We just lost some state, try to release all states */
            SDL_MinimizeWindow(window);
        }
    }

    if (FULLSCREEN_VISIBLE(window)) {
        /* Hide any other fullscreen windows */
        SDL_Window *other;
        for (other = display->windows; other; other = other->next) {
            if (other != window && FULLSCREEN_VISIBLE(other)) {
                SDL_MinimizeWindow(other);
            }
        }
    }

    display->updating_fullscreen = SDL_FALSE;

    /* See if there are any fullscreen windows */
    for (window = display->windows; window; window = window->next) {
        if (FULLSCREEN_VISIBLE(window)) {
            SDL_DisplayMode fullscreen_mode;
            if (SDL_GetWindowDisplayMode(window, &fullscreen_mode) == 0) {
                SDL_SetDisplayModeForDisplay(display, &fullscreen_mode);
                display->fullscreen_window = window;
                return;
            }
        }
    }

    /* Nope, restore the desktop mode */
    SDL_SetDisplayModeForDisplay(display, NULL);
    display->fullscreen_window = NULL;
}

SDL_Window *
SDL_CreateWindow(const char *title, int x, int y, int w, int h, Uint32 flags)
{
    const Uint32 allowed_flags = (SDL_WINDOW_FULLSCREEN |
                                  SDL_WINDOW_OPENGL |
                                  SDL_WINDOW_BORDERLESS |
                                  SDL_WINDOW_RESIZABLE |
                                  SDL_WINDOW_INPUT_GRABBED);
    SDL_VideoDisplay *display;
    SDL_Window *window;

    if (!_this) {
        /* Initialize the video system if needed */
        if (SDL_VideoInit(NULL) < 0) {
            return NULL;
        }
    }
    if (flags & SDL_WINDOW_OPENGL) {
        if (!_this->GL_CreateContext) {
            SDL_SetError("No OpenGL support in video driver");
            return NULL;
        }
        SDL_GL_LoadLibrary(NULL);
    }
    display = SDL_CurrentDisplay;
    window = (SDL_Window *)SDL_calloc(1, sizeof(*window));
    window->magic = &_this->window_magic;
    window->id = _this->next_object_id++;
    window->x = x;
    window->y = y;
    window->w = w;
    window->h = h;
    window->flags = (flags & allowed_flags);
    window->display = display;
    window->next = display->windows;
    if (display->windows) {
        display->windows->prev = window;
    }
    display->windows = window;

    if (_this->CreateWindow && _this->CreateWindow(_this, window) < 0) {
        SDL_DestroyWindow(window);
        return NULL;
    }

    if (title) {
        SDL_SetWindowTitle(window, title);
    }
    if (flags & SDL_WINDOW_MAXIMIZED) {
        SDL_MaximizeWindow(window);
    }
    if (flags & SDL_WINDOW_MINIMIZED) {
        SDL_MinimizeWindow(window);
    }
    if (flags & SDL_WINDOW_SHOWN) {
        SDL_ShowWindow(window);
    }
    SDL_UpdateWindowGrab(window);

    return window;
}

SDL_Window *
SDL_CreateWindowFrom(const void *data)
{
    SDL_VideoDisplay *display;
    SDL_Window *window;

    if (!_this) {
        SDL_UninitializedVideo();
        return NULL;
    }
    display = SDL_CurrentDisplay;
    window = (SDL_Window *)SDL_calloc(1, sizeof(*window));
    window->magic = &_this->window_magic;
    window->id = _this->next_object_id++;
    window->flags = SDL_WINDOW_FOREIGN;
    window->display = display;
    window->next = display->windows;
    if (display->windows) {
        display->windows->prev = window;
    }
    display->windows = window;

    if (!_this->CreateWindowFrom ||
        _this->CreateWindowFrom(_this, window, data) < 0) {
        SDL_DestroyWindow(window);
        return NULL;
    }
    return window;
}

int
SDL_RecreateWindow(SDL_Window * window, Uint32 flags)
{
    const Uint32 allowed_flags = (SDL_WINDOW_FULLSCREEN |
                                  SDL_WINDOW_OPENGL |
                                  SDL_WINDOW_BORDERLESS |
                                  SDL_WINDOW_RESIZABLE |
                                  SDL_WINDOW_INPUT_GRABBED |
                                  SDL_WINDOW_FOREIGN);
    char *title = window->title;

    if ((flags & SDL_WINDOW_OPENGL) && !_this->GL_CreateContext) {
        SDL_SetError("No OpenGL support in video driver");
        return -1;
    }
    if ((window->flags & SDL_WINDOW_OPENGL) != (flags & SDL_WINDOW_OPENGL)) {
        if (flags & SDL_WINDOW_OPENGL) {
            SDL_GL_LoadLibrary(NULL);
        } else {
            SDL_GL_UnloadLibrary();
        }
    }

    if (window->flags & SDL_WINDOW_FOREIGN) {
        /* Can't destroy and re-create foreign windows, hrm */
        flags |= SDL_WINDOW_FOREIGN;
    } else {
        flags &= ~SDL_WINDOW_FOREIGN;
    }

    if (_this->DestroyWindow && !(flags & SDL_WINDOW_FOREIGN)) {
        _this->DestroyWindow(_this, window);
    }

    window->title = NULL;
    window->flags = (flags & allowed_flags);

    if (_this->CreateWindow && !(flags & SDL_WINDOW_FOREIGN)) {
        if (_this->CreateWindow(_this, window) < 0) {
            if (flags & SDL_WINDOW_OPENGL) {
                SDL_GL_UnloadLibrary();
            }
            return -1;
        }
    }

    if (title) {
        SDL_SetWindowTitle(window, title);
        SDL_free(title);
    }
    if (flags & SDL_WINDOW_MAXIMIZED) {
        SDL_MaximizeWindow(window);
    }
    if (flags & SDL_WINDOW_MINIMIZED) {
        SDL_MinimizeWindow(window);
    }
    if (flags & SDL_WINDOW_SHOWN) {
        SDL_ShowWindow(window);
    }
    SDL_UpdateWindowGrab(window);

    return 0;
}

Uint32
SDL_GetWindowID(SDL_Window * window)
{
    CHECK_WINDOW_MAGIC(window, 0);

    return window->id;
}

SDL_Window *
SDL_GetWindowFromID(Uint32 id)
{
    SDL_Window *window;
    int i;

    if (!_this) {
        return NULL;
    }
    /* FIXME: Should we keep a separate hash table for these? */
    for (i = _this->num_displays; i--;) {
        SDL_VideoDisplay *display = &_this->displays[i];
        for (window = display->windows; window; window = window->next) {
            if (window->id == id) {
                return window;
            }
        }
    }
    return NULL;
}

Uint32
SDL_GetWindowFlags(SDL_Window * window)
{
    CHECK_WINDOW_MAGIC(window, 0);

    return window->flags;
}

void
SDL_SetWindowTitle(SDL_Window * window, const char *title)
{
    CHECK_WINDOW_MAGIC(window, );

    if (title == window->title) {
        return;
    }
    if (window->title) {
        SDL_free(window->title);
    }
    if (title && *title) {
        window->title = SDL_strdup(title);
    } else {
        window->title = NULL;
    }

    if (_this->SetWindowTitle) {
        _this->SetWindowTitle(_this, window);
    }
}

const char *
SDL_GetWindowTitle(SDL_Window * window)
{
    CHECK_WINDOW_MAGIC(window, "");

    return window->title ? window->title : "";
}

void
SDL_SetWindowIcon(SDL_Window * window, SDL_Surface * icon)
{
    CHECK_WINDOW_MAGIC(window, );

    if (_this->SetWindowIcon) {
        _this->SetWindowIcon(_this, window, icon);
    }
}

void*
SDL_SetWindowData(SDL_Window * window, const char *name, void *userdata)
{
    SDL_WindowUserData *prev, *data;

    CHECK_WINDOW_MAGIC(window, NULL);

    /* See if the named data already exists */
    prev = NULL;
    for (data = window->data; data; prev = data, data = data->next) {
        if (SDL_strcmp(data->name, name) == 0) {
            void *last_value = data->data;

            if (userdata) {
                /* Set the new value */
                data->data = userdata;
            } else {
                /* Delete this value */
                if (prev) {
                    prev->next = data->next;
                } else {
                    window->data = data->next;
                }
                SDL_free(data->name);
                SDL_free(data);
            }
            return last_value;
        }
    }

    /* Add new data to the window */
    if (userdata) {
        data = (SDL_WindowUserData *)SDL_malloc(sizeof(*data));
        data->name = SDL_strdup(name);
        data->data = userdata;
        data->next = window->data;
        window->data = data;
    }
    return NULL;
}

void *
SDL_GetWindowData(SDL_Window * window, const char *name)
{
    SDL_WindowUserData *data;

    CHECK_WINDOW_MAGIC(window, NULL);

    for (data = window->data; data; data = data->next) {
        if (SDL_strcmp(data->name, name) == 0) {
            return data->data;
        }
    }
    return NULL;
}

void
SDL_SetWindowPosition(SDL_Window * window, int x, int y)
{
    CHECK_WINDOW_MAGIC(window, );

    if (x != SDL_WINDOWPOS_UNDEFINED) {
        window->x = x;
    }
    if (y != SDL_WINDOWPOS_UNDEFINED) {
        window->y = y;
    }
    if (_this->SetWindowPosition) {
        _this->SetWindowPosition(_this, window);
    }
    SDL_SendWindowEvent(window, SDL_WINDOWEVENT_MOVED, x, y);
}

void
SDL_GetWindowPosition(SDL_Window * window, int *x, int *y)
{
    CHECK_WINDOW_MAGIC(window, );

    if (x) {
        *x = window->x;
    }
    if (y) {
        *y = window->y;
    }
}

void
SDL_SetWindowSize(SDL_Window * window, int w, int h)
{
    CHECK_WINDOW_MAGIC(window, );

    window->w = w;
    window->h = h;

    if (_this->SetWindowSize) {
        _this->SetWindowSize(_this, window);
    }
    SDL_SendWindowEvent(window, SDL_WINDOWEVENT_RESIZED, w, h);
}

void
SDL_GetWindowSize(SDL_Window * window, int *w, int *h)
{
    if (window) {
        if (w) {
            *w = window->w;
        }
        if (h) {
            *h = window->h;
        }
    } else {
        if (w) {
            *w = 0;
        }
        if (h) {
            *h = 0;
        }
    }
}

void
SDL_ShowWindow(SDL_Window * window)
{
    CHECK_WINDOW_MAGIC(window, );

    if (window->flags & SDL_WINDOW_SHOWN) {
        return;
    }

    if (_this->ShowWindow) {
        _this->ShowWindow(_this, window);
    }
    SDL_SendWindowEvent(window, SDL_WINDOWEVENT_SHOWN, 0, 0);
}

void
SDL_HideWindow(SDL_Window * window)
{
    CHECK_WINDOW_MAGIC(window, );

    if (!(window->flags & SDL_WINDOW_SHOWN)) {
        return;
    }

    if (_this->HideWindow) {
        _this->HideWindow(_this, window);
    }
    SDL_SendWindowEvent(window, SDL_WINDOWEVENT_HIDDEN, 0, 0);
}

void
SDL_RaiseWindow(SDL_Window * window)
{
    CHECK_WINDOW_MAGIC(window, );

    if (!(window->flags & SDL_WINDOW_SHOWN)) {
        return;
    }
    if (_this->RaiseWindow) {
        _this->RaiseWindow(_this, window);
    } else {
        /* FIXME: What we really want is a way to request focus */
        SDL_SendWindowEvent(window, SDL_WINDOWEVENT_FOCUS_GAINED, 0, 0);
    }
}

void
SDL_MaximizeWindow(SDL_Window * window)
{
    CHECK_WINDOW_MAGIC(window, );

    if (window->flags & SDL_WINDOW_MAXIMIZED) {
        return;
    }

    if (_this->MaximizeWindow) {
        _this->MaximizeWindow(_this, window);
    }
    SDL_SendWindowEvent(window, SDL_WINDOWEVENT_MAXIMIZED, 0, 0);
}

void
SDL_MinimizeWindow(SDL_Window * window)
{
    CHECK_WINDOW_MAGIC(window, );

    if (window->flags & SDL_WINDOW_MINIMIZED) {
        return;
    }

    if (_this->MinimizeWindow) {
        _this->MinimizeWindow(_this, window);
    }
    SDL_SendWindowEvent(window, SDL_WINDOWEVENT_MINIMIZED, 0, 0);
}

void
SDL_RestoreWindow(SDL_Window * window)
{
    CHECK_WINDOW_MAGIC(window, );

    if (!(window->flags & (SDL_WINDOW_MAXIMIZED | SDL_WINDOW_MINIMIZED))) {
        return;
    }

    if (_this->RestoreWindow) {
        _this->RestoreWindow(_this, window);
    }
    SDL_SendWindowEvent(window, SDL_WINDOWEVENT_RESTORED, 0, 0);
}

int
SDL_SetWindowFullscreen(SDL_Window * window, int fullscreen)
{
    CHECK_WINDOW_MAGIC(window, -1);

    if (fullscreen) {
        fullscreen = SDL_WINDOW_FULLSCREEN;
    }
    if ((window->flags & SDL_WINDOW_FULLSCREEN) == fullscreen) {
        return 0;
    }
    if (fullscreen) {
        window->flags |= SDL_WINDOW_FULLSCREEN;

        SDL_UpdateFullscreenMode(window, SDL_TRUE);
    } else {
        window->flags &= ~SDL_WINDOW_FULLSCREEN;

        SDL_UpdateFullscreenMode(window, SDL_FALSE);
    }
    return 0;
}

static SDL_Surface *
SDL_CreateWindowFramebuffer(SDL_Window * window)
{
    Uint32 format;
    void *pixels;
    int pitch;
    int bpp;
    Uint32 Rmask, Gmask, Bmask, Amask;

    if (!_this->CreateWindowFramebuffer || !_this->UpdateWindowFramebuffer) {
        return NULL;
    }

    if (_this->CreateWindowFramebuffer(_this, window, &format, &pixels, &pitch) < 0) {
        return NULL;
    }

    if (!SDL_PixelFormatEnumToMasks(format, &bpp, &Rmask, &Gmask, &Bmask, &Amask)) {
        return NULL;
    }

    return SDL_CreateRGBSurfaceFrom(pixels, window->w, window->h, bpp, pitch, Rmask, Gmask, Bmask, Amask);
}

SDL_Surface *
SDL_GetWindowSurface(SDL_Window * window)
{
    CHECK_WINDOW_MAGIC(window, NULL);

    if (!window->surface) {
        window->surface = SDL_CreateWindowFramebuffer(window);
        if (window->surface) {
            window->surface->refcount = 0x7FFFFFF;
        }
    }
    return window->surface;
}

int
SDL_UpdateWindowSurface(SDL_Window * window)
{
    SDL_Rect full_rect;

    CHECK_WINDOW_MAGIC(window, -1);

    full_rect.x = 0;
    full_rect.y = 0;
    full_rect.w = window->w;
    full_rect.h = window->h;
    return SDL_UpdateWindowSurfaceRects(window, 1, &full_rect);
}

int
SDL_UpdateWindowSurfaceRects(SDL_Window * window,
                             int numrects, SDL_Rect * rects)
{
    CHECK_WINDOW_MAGIC(window, -1);

    if (!window->surface) {
        SDL_SetError("Window surface is invalid, please call SDL_GetWindowSurface() to get a new surface");
        return -1;
    }

    return _this->UpdateWindowFramebuffer(_this, window, numrects, rects);
}

void
SDL_SetWindowGrab(SDL_Window * window, int mode)
{
    CHECK_WINDOW_MAGIC(window, );

    if ((!!mode == !!(window->flags & SDL_WINDOW_INPUT_GRABBED))) {
        return;
    }
    if (mode) {
        window->flags |= SDL_WINDOW_INPUT_GRABBED;
    } else {
        window->flags &= ~SDL_WINDOW_INPUT_GRABBED;
    }
    SDL_UpdateWindowGrab(window);
}

static void
SDL_UpdateWindowGrab(SDL_Window * window)
{
    if ((window->flags & SDL_WINDOW_INPUT_FOCUS) && _this->SetWindowGrab) {
        _this->SetWindowGrab(_this, window);
    }
}

int
SDL_GetWindowGrab(SDL_Window * window)
{
    CHECK_WINDOW_MAGIC(window, 0);

    return ((window->flags & SDL_WINDOW_INPUT_GRABBED) != 0);
}

void
SDL_OnWindowShown(SDL_Window * window)
{
    SDL_RaiseWindow(window);
    SDL_UpdateFullscreenMode(window, SDL_TRUE);
}

void
SDL_OnWindowHidden(SDL_Window * window)
{
    SDL_UpdateFullscreenMode(window, SDL_FALSE);
}

void
SDL_OnWindowResized(SDL_Window * window)
{
    if (window->surface) {
        window->surface->refcount = 0;
        SDL_FreeSurface(window->surface);
        window->surface = NULL;
    }
}

void
SDL_OnWindowMinimized(SDL_Window * window)
{
    SDL_UpdateFullscreenMode(window, SDL_FALSE);
}

void
SDL_OnWindowRestored(SDL_Window * window)
{
    SDL_RaiseWindow(window);
    SDL_UpdateFullscreenMode(window, SDL_TRUE);
}

void
SDL_OnWindowFocusGained(SDL_Window * window)
{
    SDL_VideoDisplay *display = window->display;

    if (display->gamma && _this->SetDisplayGammaRamp) {
        _this->SetDisplayGammaRamp(_this, display, display->gamma);
    }
    if ((window->flags & (SDL_WINDOW_INPUT_GRABBED | SDL_WINDOW_FULLSCREEN))
        && _this->SetWindowGrab) {
        _this->SetWindowGrab(_this, window);
    }
}

void
SDL_OnWindowFocusLost(SDL_Window * window)
{
    SDL_VideoDisplay *display = window->display;

    /* If we're fullscreen on a single-head system and lose focus, minimize */
    if ((window->flags & SDL_WINDOW_FULLSCREEN) &&
        _this->num_displays == 1) {
        SDL_MinimizeWindow(window);
    }

    if (display->gamma && _this->SetDisplayGammaRamp) {
        _this->SetDisplayGammaRamp(_this, display, display->saved_gamma);
    }
    if ((window->flags & (SDL_WINDOW_INPUT_GRABBED | SDL_WINDOW_FULLSCREEN))
        && _this->SetWindowGrab) {
        _this->SetWindowGrab(_this, window);
    }
}

SDL_Window *
SDL_GetFocusWindow(void)
{
    SDL_VideoDisplay *display;
    SDL_Window *window;

    if (!_this) {
        return NULL;
    }
    display = SDL_CurrentDisplay;
    for (window = display->windows; window; window = window->next) {
        if (window->flags & SDL_WINDOW_INPUT_FOCUS) {
            return window;
        }
    }
    return NULL;
}

void
SDL_DestroyWindow(SDL_Window * window)
{
    SDL_VideoDisplay *display;

    CHECK_WINDOW_MAGIC(window, );

    /* Restore video mode, etc. */
    SDL_UpdateFullscreenMode(window, SDL_FALSE);

    if (window->surface) {
        window->surface->refcount = 0;
        SDL_FreeSurface(window->surface);
    }
    if (_this->DestroyWindowFramebuffer) {
        _this->DestroyWindowFramebuffer(_this, window);
    }
    if (_this->DestroyWindow) {
        _this->DestroyWindow(_this, window);
    }
    if (window->flags & SDL_WINDOW_OPENGL) {
        SDL_GL_UnloadLibrary();
    }

    /* Now invalidate magic */
    window->magic = NULL;

    /* Free memory associated with the window */
    if (window->title) {
        SDL_free(window->title);
    }
    while (window->data) {
        SDL_WindowUserData *data = window->data;

        window->data = data->next;
        SDL_free(data->name);
        SDL_free(data);
    }

    /* Unlink the window from the list */
    display = window->display;
    if (window->next) {
        window->next->prev = window->prev;
    }
    if (window->prev) {
        window->prev->next = window->next;
    } else {
        display->windows = window->next;
    }

    SDL_free(window);
}

SDL_bool
SDL_IsScreenSaverEnabled()
{
    if (!_this) {
        return SDL_TRUE;
    }
    return _this->suspend_screensaver ? SDL_FALSE : SDL_TRUE;
}

void
SDL_EnableScreenSaver()
{
    if (!_this) {
        return;
    }
    if (!_this->suspend_screensaver) {
        return;
    }
    _this->suspend_screensaver = SDL_FALSE;
    if (_this->SuspendScreenSaver) {
        _this->SuspendScreenSaver(_this);
    }
}

void
SDL_DisableScreenSaver()
{
    if (!_this) {
        return;
    }
    if (_this->suspend_screensaver) {
        return;
    }
    _this->suspend_screensaver = SDL_TRUE;
    if (_this->SuspendScreenSaver) {
        _this->SuspendScreenSaver(_this);
    }
}

void
SDL_VideoQuit(void)
{
    int i, j;

    if (!_this) {
        return;
    }

    /* Halt event processing before doing anything else */
    SDL_QuitQuit();
    SDL_MouseQuit();
    SDL_KeyboardQuit();
    SDL_StopEventLoop();

    SDL_EnableScreenSaver();

    /* Clean up the system video */
    for (i = _this->num_displays; i--;) {
        SDL_VideoDisplay *display = &_this->displays[i];
        while (display->windows) {
            SDL_DestroyWindow(display->windows);
        }
    }
    _this->VideoQuit(_this);

    for (i = _this->num_displays; i--;) {
        SDL_VideoDisplay *display = &_this->displays[i];
        for (j = display->num_display_modes; j--;) {
            if (display->display_modes[j].driverdata) {
                SDL_free(display->display_modes[j].driverdata);
                display->display_modes[j].driverdata = NULL;
            }
        }
        if (display->display_modes) {
            SDL_free(display->display_modes);
            display->display_modes = NULL;
        }
        if (display->desktop_mode.driverdata) {
            SDL_free(display->desktop_mode.driverdata);
            display->desktop_mode.driverdata = NULL;
        }
        if (display->gamma) {
            SDL_free(display->gamma);
            display->gamma = NULL;
        }
        if (display->driverdata) {
            SDL_free(display->driverdata);
            display->driverdata = NULL;
        }
    }
    if (_this->displays) {
        SDL_free(_this->displays);
        _this->displays = NULL;
    }
    if (_this->clipboard_text) {
        SDL_free(_this->clipboard_text);
        _this->clipboard_text = NULL;
    }
    _this->free(_this);
    _this = NULL;
}

int
SDL_GL_LoadLibrary(const char *path)
{
    int retval;

    if (!_this) {
        SDL_UninitializedVideo();
        return -1;
    }
    if (_this->gl_config.driver_loaded) {
        if (path && SDL_strcmp(path, _this->gl_config.driver_path) != 0) {
            SDL_SetError("OpenGL library already loaded");
            return -1;
        }
        retval = 0;
    } else {
        if (!_this->GL_LoadLibrary) {
            SDL_SetError("No dynamic GL support in video driver");
            return -1;
        }
        retval = _this->GL_LoadLibrary(_this, path);
    }
    if (retval == 0) {
        ++_this->gl_config.driver_loaded;
    }
    return (retval);
}

void *
SDL_GL_GetProcAddress(const char *proc)
{
    void *func;

    if (!_this) {
        SDL_UninitializedVideo();
        return NULL;
    }
    func = NULL;
    if (_this->GL_GetProcAddress) {
        if (_this->gl_config.driver_loaded) {
            func = _this->GL_GetProcAddress(_this, proc);
        } else {
            SDL_SetError("No GL driver has been loaded");
        }
    } else {
        SDL_SetError("No dynamic GL support in video driver");
    }
    return func;
}

void
SDL_GL_UnloadLibrary(void)
{
    if (!_this) {
        SDL_UninitializedVideo();
        return;
    }
    if (_this->gl_config.driver_loaded > 0) {
        if (--_this->gl_config.driver_loaded > 0) {
            return;
        }
        if (_this->GL_UnloadLibrary) {
            _this->GL_UnloadLibrary(_this);
        }
    }
}

SDL_bool
SDL_GL_ExtensionSupported(const char *extension)
{
#if SDL_VIDEO_OPENGL || SDL_VIDEO_OPENGL_ES
    const GLubyte *(APIENTRY * glGetStringFunc) (GLenum);
    const char *extensions;
    const char *start;
    const char *where, *terminator;

    /* Extension names should not have spaces. */
    where = SDL_strchr(extension, ' ');
    if (where || *extension == '\0') {
        return SDL_FALSE;
    }
    /* See if there's an environment variable override */
    start = SDL_getenv(extension);
    if (start && *start == '0') {
        return SDL_FALSE;
    }
    /* Lookup the available extensions */
    glGetStringFunc = SDL_GL_GetProcAddress("glGetString");
    if (glGetStringFunc) {
        extensions = (const char *) glGetStringFunc(GL_EXTENSIONS);
    } else {
        extensions = NULL;
    }
    if (!extensions) {
        return SDL_FALSE;
    }
    /*
     * It takes a bit of care to be fool-proof about parsing the OpenGL
     * extensions string. Don't be fooled by sub-strings, etc.
     */

    start = extensions;

    for (;;) {
        where = SDL_strstr(start, extension);
        if (!where)
            break;

        terminator = where + SDL_strlen(extension);
        if (where == start || *(where - 1) == ' ')
            if (*terminator == ' ' || *terminator == '\0')
                return SDL_TRUE;

        start = terminator;
    }
    return SDL_FALSE;
#else
    return SDL_FALSE;
#endif
}

int
SDL_GL_SetAttribute(SDL_GLattr attr, int value)
{
#if SDL_VIDEO_OPENGL || SDL_VIDEO_OPENGL_ES
    int retval;

    if (!_this) {
        SDL_UninitializedVideo();
        return -1;
    }
    retval = 0;
    switch (attr) {
    case SDL_GL_RED_SIZE:
        _this->gl_config.red_size = value;
        break;
    case SDL_GL_GREEN_SIZE:
        _this->gl_config.green_size = value;
        break;
    case SDL_GL_BLUE_SIZE:
        _this->gl_config.blue_size = value;
        break;
    case SDL_GL_ALPHA_SIZE:
        _this->gl_config.alpha_size = value;
        break;
    case SDL_GL_DOUBLEBUFFER:
        _this->gl_config.double_buffer = value;
        break;
    case SDL_GL_BUFFER_SIZE:
        _this->gl_config.buffer_size = value;
        break;
    case SDL_GL_DEPTH_SIZE:
        _this->gl_config.depth_size = value;
        break;
    case SDL_GL_STENCIL_SIZE:
        _this->gl_config.stencil_size = value;
        break;
    case SDL_GL_ACCUM_RED_SIZE:
        _this->gl_config.accum_red_size = value;
        break;
    case SDL_GL_ACCUM_GREEN_SIZE:
        _this->gl_config.accum_green_size = value;
        break;
    case SDL_GL_ACCUM_BLUE_SIZE:
        _this->gl_config.accum_blue_size = value;
        break;
    case SDL_GL_ACCUM_ALPHA_SIZE:
        _this->gl_config.accum_alpha_size = value;
        break;
    case SDL_GL_STEREO:
        _this->gl_config.stereo = value;
        break;
    case SDL_GL_MULTISAMPLEBUFFERS:
        _this->gl_config.multisamplebuffers = value;
        break;
    case SDL_GL_MULTISAMPLESAMPLES:
        _this->gl_config.multisamplesamples = value;
        break;
    case SDL_GL_ACCELERATED_VISUAL:
        _this->gl_config.accelerated = value;
        break;
    case SDL_GL_RETAINED_BACKING:
        _this->gl_config.retained_backing = value;
        break;
    case SDL_GL_CONTEXT_MAJOR_VERSION:
        _this->gl_config.major_version = value;
        break;
    case SDL_GL_CONTEXT_MINOR_VERSION:
        _this->gl_config.minor_version = value;
        break;
    default:
        SDL_SetError("Unknown OpenGL attribute");
        retval = -1;
        break;
    }
    return retval;
#else
    SDL_Unsupported();
    return -1;
#endif /* SDL_VIDEO_OPENGL */
}

int
SDL_GL_GetAttribute(SDL_GLattr attr, int *value)
{
#if SDL_VIDEO_OPENGL || SDL_VIDEO_OPENGL_ES
    void (APIENTRY * glGetIntegervFunc) (GLenum pname, GLint * params);
    GLenum(APIENTRY * glGetErrorFunc) (void);
    GLenum attrib = 0;
    GLenum error = 0;

    glGetIntegervFunc = SDL_GL_GetProcAddress("glGetIntegerv");
    if (!glGetIntegervFunc) {
        return -1;
    }

    glGetErrorFunc = SDL_GL_GetProcAddress("glGetError");
    if (!glGetErrorFunc) {
        return -1;
    }

    /* Clear value in any case */
    *value = 0;

    switch (attr) {
    case SDL_GL_RETAINED_BACKING:
        *value = _this->gl_config.retained_backing;
        return 0;
    case SDL_GL_RED_SIZE:
        attrib = GL_RED_BITS;
        break;
    case SDL_GL_BLUE_SIZE:
        attrib = GL_BLUE_BITS;
        break;
    case SDL_GL_GREEN_SIZE:
        attrib = GL_GREEN_BITS;
        break;
    case SDL_GL_ALPHA_SIZE:
        attrib = GL_ALPHA_BITS;
        break;
    case SDL_GL_DOUBLEBUFFER:
#ifndef SDL_VIDEO_OPENGL_ES
        attrib = GL_DOUBLEBUFFER;
        break;
#else
        /* OpenGL ES 1.0 and above specifications have EGL_SINGLE_BUFFER      */
        /* parameter which switches double buffer to single buffer. OpenGL ES */
        /* SDL driver must set proper value after initialization              */
        *value = _this->gl_config.double_buffer;
        return 0;
#endif
    case SDL_GL_DEPTH_SIZE:
        attrib = GL_DEPTH_BITS;
        break;
    case SDL_GL_STENCIL_SIZE:
        attrib = GL_STENCIL_BITS;
        break;
#ifndef SDL_VIDEO_OPENGL_ES
    case SDL_GL_ACCUM_RED_SIZE:
        attrib = GL_ACCUM_RED_BITS;
        break;
    case SDL_GL_ACCUM_GREEN_SIZE:
        attrib = GL_ACCUM_GREEN_BITS;
        break;
    case SDL_GL_ACCUM_BLUE_SIZE:
        attrib = GL_ACCUM_BLUE_BITS;
        break;
    case SDL_GL_ACCUM_ALPHA_SIZE:
        attrib = GL_ACCUM_ALPHA_BITS;
        break;
    case SDL_GL_STEREO:
        attrib = GL_STEREO;
        break;
#else
    case SDL_GL_ACCUM_RED_SIZE:
    case SDL_GL_ACCUM_GREEN_SIZE:
    case SDL_GL_ACCUM_BLUE_SIZE:
    case SDL_GL_ACCUM_ALPHA_SIZE:
    case SDL_GL_STEREO:
        /* none of these are supported in OpenGL ES */
        *value = 0;
        return 0;
#endif
    case SDL_GL_MULTISAMPLEBUFFERS:
#ifndef SDL_VIDEO_OPENGL_ES
        attrib = GL_SAMPLE_BUFFERS_ARB;
#else
        attrib = GL_SAMPLE_BUFFERS;
#endif
        break;
    case SDL_GL_MULTISAMPLESAMPLES:
#ifndef SDL_VIDEO_OPENGL_ES
        attrib = GL_SAMPLES_ARB;
#else
        attrib = GL_SAMPLES;
#endif
        break;
    case SDL_GL_BUFFER_SIZE:
        {
            GLint bits = 0;
            GLint component;

            /*
             * there doesn't seem to be a single flag in OpenGL
             * for this!
             */
            glGetIntegervFunc(GL_RED_BITS, &component);
            bits += component;
            glGetIntegervFunc(GL_GREEN_BITS, &component);
            bits += component;
            glGetIntegervFunc(GL_BLUE_BITS, &component);
            bits += component;
            glGetIntegervFunc(GL_ALPHA_BITS, &component);
            bits += component;

            *value = bits;
            return 0;
        }
    case SDL_GL_ACCELERATED_VISUAL:
        {
            /* FIXME: How do we get this information? */
            *value = (_this->gl_config.accelerated != 0);
            return 0;
        }
    default:
        SDL_SetError("Unknown OpenGL attribute");
        return -1;
    }

    glGetIntegervFunc(attrib, (GLint *) value);
    error = glGetErrorFunc();
    if (error != GL_NO_ERROR) {
        switch (error) {
        case GL_INVALID_ENUM:
            {
                SDL_SetError("OpenGL error: GL_INVALID_ENUM");
            }
            break;
        case GL_INVALID_VALUE:
            {
                SDL_SetError("OpenGL error: GL_INVALID_VALUE");
            }
            break;
        default:
            {
                SDL_SetError("OpenGL error: %08X", error);
            }
            break;
        }
        return -1;
    }
    return 0;
#else
    SDL_Unsupported();
    return -1;
#endif /* SDL_VIDEO_OPENGL */
}

SDL_GLContext
SDL_GL_CreateContext(SDL_Window * window)
{
    CHECK_WINDOW_MAGIC(window, NULL);

    if (!(window->flags & SDL_WINDOW_OPENGL)) {
        SDL_SetError("The specified window isn't an OpenGL window");
        return NULL;
    }
    return _this->GL_CreateContext(_this, window);
}

int
SDL_GL_MakeCurrent(SDL_Window * window, SDL_GLContext context)
{
    CHECK_WINDOW_MAGIC(window, -1);

    if (!(window->flags & SDL_WINDOW_OPENGL)) {
        SDL_SetError("The specified window isn't an OpenGL window");
        return -1;
    }
    if (!context) {
        window = NULL;
    }
    return _this->GL_MakeCurrent(_this, window, context);
}

int
SDL_GL_SetSwapInterval(int interval)
{
    if (!_this) {
        SDL_UninitializedVideo();
        return -1;
    }
    if (_this->GL_SetSwapInterval) {
        return _this->GL_SetSwapInterval(_this, interval);
    } else {
        SDL_SetError("Setting the swap interval is not supported");
        return -1;
    }
}

int
SDL_GL_GetSwapInterval(void)
{
    if (!_this) {
        SDL_UninitializedVideo();
        return -1;
    }
    if (_this->GL_GetSwapInterval) {
        return _this->GL_GetSwapInterval(_this);
    } else {
        SDL_SetError("Getting the swap interval is not supported");
        return -1;
    }
}

void
SDL_GL_SwapWindow(SDL_Window * window)
{
    CHECK_WINDOW_MAGIC(window, );

    if (!(window->flags & SDL_WINDOW_OPENGL)) {
        SDL_SetError("The specified window isn't an OpenGL window");
        return;
    }
    _this->GL_SwapWindow(_this, window);
}

void
SDL_GL_DeleteContext(SDL_GLContext context)
{
    if (!_this || !_this->gl_data || !context) {
        return;
    }
    _this->GL_MakeCurrent(_this, NULL, NULL);
    _this->GL_DeleteContext(_this, context);
}

#if 0                           // FIXME
/*
 * Utility function used by SDL_WM_SetIcon(); flags & 1 for color key, flags
 * & 2 for alpha channel.
 */
static void
CreateMaskFromColorKeyOrAlpha(SDL_Surface * icon, Uint8 * mask, int flags)
{
    int x, y;
    Uint32 colorkey;
#define SET_MASKBIT(icon, x, y, mask) \
	mask[(y*((icon->w+7)/8))+(x/8)] &= ~(0x01<<(7-(x%8)))

    colorkey = icon->format->colorkey;
    switch (icon->format->BytesPerPixel) {
    case 1:
        {
            Uint8 *pixels;
            for (y = 0; y < icon->h; ++y) {
                pixels = (Uint8 *) icon->pixels + y * icon->pitch;
                for (x = 0; x < icon->w; ++x) {
                    if (*pixels++ == colorkey) {
                        SET_MASKBIT(icon, x, y, mask);
                    }
                }
            }
        }
        break;

    case 2:
        {
            Uint16 *pixels;
            for (y = 0; y < icon->h; ++y) {
                pixels = (Uint16 *) icon->pixels + y * icon->pitch / 2;
                for (x = 0; x < icon->w; ++x) {
                    if ((flags & 1) && *pixels == colorkey) {
                        SET_MASKBIT(icon, x, y, mask);
                    } else if ((flags & 2)
                               && (*pixels & icon->format->Amask) == 0) {
                        SET_MASKBIT(icon, x, y, mask);
                    }
                    pixels++;
                }
            }
        }
        break;

    case 4:
        {
            Uint32 *pixels;
            for (y = 0; y < icon->h; ++y) {
                pixels = (Uint32 *) icon->pixels + y * icon->pitch / 4;
                for (x = 0; x < icon->w; ++x) {
                    if ((flags & 1) && *pixels == colorkey) {
                        SET_MASKBIT(icon, x, y, mask);
                    } else if ((flags & 2)
                               && (*pixels & icon->format->Amask) == 0) {
                        SET_MASKBIT(icon, x, y, mask);
                    }
                    pixels++;
                }
            }
        }
        break;
    }
}

/*
 * Sets the window manager icon for the display window.
 */
void
SDL_WM_SetIcon(SDL_Surface * icon, Uint8 * mask)
{
    if (icon && _this->SetIcon) {
        /* Generate a mask if necessary, and create the icon! */
        if (mask == NULL) {
            int mask_len = icon->h * (icon->w + 7) / 8;
            int flags = 0;
            mask = (Uint8 *) SDL_malloc(mask_len);
            if (mask == NULL) {
                return;
            }
            SDL_memset(mask, ~0, mask_len);
            if (icon->flags & SDL_SRCCOLORKEY)
                flags |= 1;
            if (icon->flags & SDL_SRCALPHA)
                flags |= 2;
            if (flags) {
                CreateMaskFromColorKeyOrAlpha(icon, mask, flags);
            }
            _this->SetIcon(_this, icon, mask);
            SDL_free(mask);
        } else {
            _this->SetIcon(_this, icon, mask);
        }
    }
}
#endif

SDL_bool
SDL_GetWindowWMInfo(SDL_Window * window, struct SDL_SysWMinfo *info)
{
    CHECK_WINDOW_MAGIC(window, SDL_FALSE);

    if (!info) {
        return SDL_FALSE;
    }
    info->subsystem = SDL_SYSWM_UNKNOWN;

    if (!_this->GetWindowWMInfo) {
        return SDL_FALSE;
    }
    return (_this->GetWindowWMInfo(_this, window, info));
}

void
SDL_StartTextInput(void)
{
    if (_this && _this->StartTextInput) {
        _this->StartTextInput(_this);
    }
    SDL_EventState(SDL_TEXTINPUT, SDL_ENABLE);
    SDL_EventState(SDL_TEXTEDITING, SDL_ENABLE);
}

void
SDL_StopTextInput(void)
{
    if (_this && _this->StopTextInput) {
        _this->StopTextInput(_this);
    }
    SDL_EventState(SDL_TEXTINPUT, SDL_DISABLE);
    SDL_EventState(SDL_TEXTEDITING, SDL_DISABLE);
}

void
SDL_SetTextInputRect(SDL_Rect *rect)
{
    if (_this && _this->SetTextInputRect) {
        _this->SetTextInputRect(_this, rect);
    }
}

/* vi: set ts=4 sw=4 expandtab: */