view src/video/SDL_renderer_sw.c @ 3474:1edb86163d62

Of COURSE that trick wouldn't work on all renderers. Fall back to something for now, hopefully figure out a better way to do this later. If we have to, we can use vertical line and horizontal line textures for vertical and horizontal lines, and then create custom textures for diagonal lines and software render those. It's terrible, but at least it would be pixel perfect.
author Sam Lantinga <slouken@libsdl.org>
date Sat, 21 Nov 2009 07:22:59 +0000
parents 9f62f47d989b
children 0267b8b1595c
line wrap: on
line source

/*
    SDL - Simple DirectMedia Layer
    Copyright (C) 1997-2009 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"

#include "SDL_video.h"
#include "SDL_sysvideo.h"
#include "SDL_pixels_c.h"
#include "SDL_rect_c.h"
#include "SDL_yuv_sw_c.h"


/* SDL surface based renderer implementation */

static SDL_Renderer *SW_CreateRenderer(SDL_Window * window, Uint32 flags);
static int SW_ActivateRenderer(SDL_Renderer * renderer);
static int SW_DisplayModeChanged(SDL_Renderer * renderer);
static int SW_CreateTexture(SDL_Renderer * renderer, SDL_Texture * texture);
static int SW_QueryTexturePixels(SDL_Renderer * renderer,
                                 SDL_Texture * texture, void **pixels,
                                 int *pitch);
static int SW_SetTexturePalette(SDL_Renderer * renderer,
                                SDL_Texture * texture,
                                const SDL_Color * colors, int firstcolor,
                                int ncolors);
static int SW_GetTexturePalette(SDL_Renderer * renderer,
                                SDL_Texture * texture, SDL_Color * colors,
                                int firstcolor, int ncolors);
static int SW_SetTextureColorMod(SDL_Renderer * renderer,
                                 SDL_Texture * texture);
static int SW_SetTextureAlphaMod(SDL_Renderer * renderer,
                                 SDL_Texture * texture);
static int SW_SetTextureBlendMode(SDL_Renderer * renderer,
                                  SDL_Texture * texture);
static int SW_SetTextureScaleMode(SDL_Renderer * renderer,
                                  SDL_Texture * texture);
static int SW_UpdateTexture(SDL_Renderer * renderer, SDL_Texture * texture,
                            const SDL_Rect * rect, const void *pixels,
                            int pitch);
static int SW_LockTexture(SDL_Renderer * renderer, SDL_Texture * texture,
                          const SDL_Rect * rect, int markDirty, void **pixels,
                          int *pitch);
static void SW_UnlockTexture(SDL_Renderer * renderer, SDL_Texture * texture);
static int SW_RenderPoint(SDL_Renderer * renderer, int x, int y);
static int SW_RenderLine(SDL_Renderer * renderer, int x1, int y1, int x2,
                         int y2);
static int SW_RenderFill(SDL_Renderer * renderer, const SDL_Rect * rect);
static int SW_RenderCopy(SDL_Renderer * renderer, SDL_Texture * texture,
                         const SDL_Rect * srcrect, const SDL_Rect * dstrect);
static int SW_RenderReadPixels(SDL_Renderer * renderer, const SDL_Rect * rect,
                               Uint32 format, void * pixels, int pitch);
static int SW_RenderWritePixels(SDL_Renderer * renderer, const SDL_Rect * rect,
                                Uint32 format, const void * pixels, int pitch);
static void SW_RenderPresent(SDL_Renderer * renderer);
static void SW_DestroyTexture(SDL_Renderer * renderer, SDL_Texture * texture);
static void SW_DestroyRenderer(SDL_Renderer * renderer);


SDL_RenderDriver SW_RenderDriver = {
    SW_CreateRenderer,
    {
     "software",
     (SDL_RENDERER_SINGLEBUFFER | SDL_RENDERER_PRESENTCOPY |
      SDL_RENDERER_PRESENTFLIP2 | SDL_RENDERER_PRESENTFLIP3 |
      SDL_RENDERER_PRESENTDISCARD | SDL_RENDERER_PRESENTVSYNC),
     (SDL_TEXTUREMODULATE_NONE | SDL_TEXTUREMODULATE_COLOR |
      SDL_TEXTUREMODULATE_ALPHA),
     (SDL_BLENDMODE_NONE | SDL_BLENDMODE_MASK |
      SDL_BLENDMODE_BLEND | SDL_BLENDMODE_ADD | SDL_BLENDMODE_MOD),
     (SDL_TEXTURESCALEMODE_NONE | SDL_TEXTURESCALEMODE_FAST),
     14,
     {
      SDL_PIXELFORMAT_INDEX8,
      SDL_PIXELFORMAT_RGB555,
      SDL_PIXELFORMAT_RGB565,
      SDL_PIXELFORMAT_RGB888,
      SDL_PIXELFORMAT_BGR888,
      SDL_PIXELFORMAT_ARGB8888,
      SDL_PIXELFORMAT_RGBA8888,
      SDL_PIXELFORMAT_ABGR8888,
      SDL_PIXELFORMAT_BGRA8888,
      SDL_PIXELFORMAT_YV12,
      SDL_PIXELFORMAT_IYUV,
      SDL_PIXELFORMAT_YUY2,
      SDL_PIXELFORMAT_UYVY,
      SDL_PIXELFORMAT_YVYU},
     0,
     0}
};

typedef struct
{
    Uint32 format;
    SDL_bool updateSize;
    int current_texture;
    SDL_Texture *texture[3];
    SDL_Surface surface;
    SDL_Renderer *renderer;
    SDL_DirtyRectList dirty;
} SW_RenderData;

static SDL_Texture *
CreateTexture(SDL_Renderer * renderer, Uint32 format, int w, int h)
{
    SDL_Texture *texture;

    texture = (SDL_Texture *) SDL_calloc(1, sizeof(*texture));
    if (!texture) {
        SDL_OutOfMemory();
        return NULL;
    }

    texture->format = format;
    texture->access = SDL_TEXTUREACCESS_STREAMING;
    texture->w = w;
    texture->h = h;
    texture->renderer = renderer;

    if (renderer->CreateTexture(renderer, texture) < 0) {
        SDL_free(texture);
        return NULL;
    }
    return texture;
}

static void
DestroyTexture(SDL_Renderer * renderer, SDL_Texture * texture)
{
    renderer->DestroyTexture(renderer, texture);
    SDL_free(texture);
}

static int
DisplayPaletteChanged(void *userdata, SDL_Palette * palette)
{
    SW_RenderData *data = (SW_RenderData *) userdata;
    int i;

    for (i = 0; i < SDL_arraysize(data->texture); ++i) {
        if (data->texture[i] && data->renderer->SetTexturePalette) {
            data->renderer->SetTexturePalette(data->renderer,
                                              data->texture[i],
                                              palette->colors, 0,
                                              palette->ncolors);
        }
    }
    return 0;
}

void
Setup_SoftwareRenderer(SDL_Renderer * renderer)
{
    renderer->CreateTexture = SW_CreateTexture;
    renderer->QueryTexturePixels = SW_QueryTexturePixels;
    renderer->SetTexturePalette = SW_SetTexturePalette;
    renderer->GetTexturePalette = SW_GetTexturePalette;
    renderer->SetTextureColorMod = SW_SetTextureColorMod;
    renderer->SetTextureAlphaMod = SW_SetTextureAlphaMod;
    renderer->SetTextureBlendMode = SW_SetTextureBlendMode;
    renderer->SetTextureScaleMode = SW_SetTextureScaleMode;
    renderer->UpdateTexture = SW_UpdateTexture;
    renderer->LockTexture = SW_LockTexture;
    renderer->UnlockTexture = SW_UnlockTexture;
    renderer->DestroyTexture = SW_DestroyTexture;

    renderer->info.mod_modes = SW_RenderDriver.info.mod_modes;
    renderer->info.blend_modes = SW_RenderDriver.info.blend_modes;
    renderer->info.scale_modes = SW_RenderDriver.info.scale_modes;
    renderer->info.num_texture_formats =
        SW_RenderDriver.info.num_texture_formats;
    SDL_memcpy(renderer->info.texture_formats,
               SW_RenderDriver.info.texture_formats,
               sizeof(renderer->info.texture_formats));;
    renderer->info.max_texture_width = SW_RenderDriver.info.max_texture_width;
    renderer->info.max_texture_height =
        SW_RenderDriver.info.max_texture_height;
}

SDL_Renderer *
SW_CreateRenderer(SDL_Window * window, Uint32 flags)
{
    SDL_VideoDisplay *display = SDL_GetDisplayFromWindow(window);
    SDL_DisplayMode *displayMode = &display->current_mode;
    SDL_Renderer *renderer;
    SW_RenderData *data;
    int i, n;
    int bpp;
    Uint32 Rmask, Gmask, Bmask, Amask;
    Uint32 renderer_flags;
    const char *desired_driver;

    if (!SDL_PixelFormatEnumToMasks
        (displayMode->format, &bpp, &Rmask, &Gmask, &Bmask, &Amask)) {
        SDL_SetError("Unknown display format");
        return NULL;
    }

    renderer = (SDL_Renderer *) SDL_calloc(1, sizeof(*renderer));
    if (!renderer) {
        SDL_OutOfMemory();
        return NULL;
    }

    data = (SW_RenderData *) SDL_calloc(1, sizeof(*data));
    if (!data) {
        SW_DestroyRenderer(renderer);
        SDL_OutOfMemory();
        return NULL;
    }
    renderer->ActivateRenderer = SW_ActivateRenderer;
    renderer->DisplayModeChanged = SW_DisplayModeChanged;

    renderer->RenderPoint = SW_RenderPoint;
    renderer->RenderLine = SW_RenderLine;
    renderer->RenderFill = SW_RenderFill;
    renderer->RenderCopy = SW_RenderCopy;
    renderer->RenderReadPixels = SW_RenderReadPixels;
    renderer->RenderWritePixels = SW_RenderWritePixels;
    renderer->RenderPresent = SW_RenderPresent;
    renderer->DestroyRenderer = SW_DestroyRenderer;
    renderer->info.name = SW_RenderDriver.info.name;
    renderer->info.flags = 0;
    renderer->window = window->id;
    renderer->driverdata = data;
    Setup_SoftwareRenderer(renderer);

    if (flags & SDL_RENDERER_PRESENTFLIP2) {
        renderer->info.flags |= SDL_RENDERER_PRESENTFLIP2;
        n = 2;
    } else if (flags & SDL_RENDERER_PRESENTFLIP3) {
        renderer->info.flags |= SDL_RENDERER_PRESENTFLIP3;
        n = 3;
    } else {
        renderer->info.flags |= SDL_RENDERER_PRESENTCOPY;
        n = 1;
    }
    data->format = displayMode->format;

    /* Find a render driver that we can use to display data */
    renderer_flags = (SDL_RENDERER_SINGLEBUFFER |
                      SDL_RENDERER_PRESENTDISCARD);
    if (flags & SDL_RENDERER_PRESENTVSYNC) {
        renderer_flags |= SDL_RENDERER_PRESENTVSYNC;
    }
    desired_driver = SDL_getenv("SDL_VIDEO_RENDERER_SWDRIVER");
    for (i = 0; i < display->num_render_drivers; ++i) {
        SDL_RenderDriver *driver = &display->render_drivers[i];
        if (driver->info.name == SW_RenderDriver.info.name) {
            continue;
        }
        if (desired_driver
            && SDL_strcasecmp(desired_driver, driver->info.name) != 0) {
            continue;
        }
        data->renderer = driver->CreateRenderer(window, renderer_flags);
        if (data->renderer) {
            break;
        }
    }
    if (i == display->num_render_drivers) {
        SW_DestroyRenderer(renderer);
        SDL_SetError("Couldn't find display render driver");
        return NULL;
    }
    if (data->renderer->info.flags & SDL_RENDERER_PRESENTVSYNC) {
        renderer->info.flags |= SDL_RENDERER_PRESENTVSYNC;
    }

    /* Create the textures we'll use for display */
    for (i = 0; i < n; ++i) {
        data->texture[i] =
            CreateTexture(data->renderer, data->format, window->w, window->h);
        if (!data->texture[i]) {
            SW_DestroyRenderer(renderer);
            return NULL;
        }
    }
    data->current_texture = 0;

    /* Create a surface we'll use for rendering */
    data->surface.flags = SDL_PREALLOC;
    data->surface.format = SDL_AllocFormat(bpp, Rmask, Gmask, Bmask, Amask);
    if (!data->surface.format) {
        SW_DestroyRenderer(renderer);
        return NULL;
    }
    SDL_SetSurfacePalette(&data->surface, display->palette);

    /* Set up a palette watch on the display palette */
    if (display->palette) {
        SDL_AddPaletteWatch(display->palette, DisplayPaletteChanged, data);
    }

    return renderer;
}

static int
SW_ActivateRenderer(SDL_Renderer * renderer)
{
    SW_RenderData *data = (SW_RenderData *) renderer->driverdata;
    SDL_Window *window = SDL_GetWindowFromID(renderer->window);
    int i, n;

    if (data->renderer && data->renderer->ActivateRenderer) {
        if (data->renderer->ActivateRenderer(data->renderer) < 0) {
            return -1;
        }
    }
    if (data->updateSize) {
        /* Recreate the textures for the new window size */
        if (renderer->info.flags & SDL_RENDERER_PRESENTFLIP2) {
            n = 2;
        } else if (renderer->info.flags & SDL_RENDERER_PRESENTFLIP3) {
            n = 3;
        } else {
            n = 1;
        }
        for (i = 0; i < n; ++i) {
            if (data->texture[i]) {
                DestroyTexture(data->renderer, data->texture[i]);
                data->texture[i] = 0;
            }
        }
        for (i = 0; i < n; ++i) {
            data->texture[i] =
                CreateTexture(data->renderer, data->format, window->w,
                              window->h);
            if (!data->texture[i]) {
                return -1;
            }
        }
        data->updateSize = SDL_FALSE;
    }
    return 0;
}

static int
SW_DisplayModeChanged(SDL_Renderer * renderer)
{
    SW_RenderData *data = (SW_RenderData *) renderer->driverdata;

    if (data->renderer && data->renderer->DisplayModeChanged) {
        if (data->renderer->DisplayModeChanged(data->renderer) < 0) {
            return -1;
        }
    }
    /* Rebind the context to the window area */
    data->updateSize = SDL_TRUE;
    return SW_ActivateRenderer(renderer);
}

static int
SW_CreateTexture(SDL_Renderer * renderer, SDL_Texture * texture)
{
    if (SDL_ISPIXELFORMAT_FOURCC(texture->format)) {
        texture->driverdata =
            SDL_SW_CreateYUVTexture(texture->format, texture->w, texture->h);
    } else {
        int bpp;
        Uint32 Rmask, Gmask, Bmask, Amask;

        if (!SDL_PixelFormatEnumToMasks
            (texture->format, &bpp, &Rmask, &Gmask, &Bmask, &Amask)) {
            SDL_SetError("Unknown texture format");
            return -1;
        }

        texture->driverdata =
            SDL_CreateRGBSurface(0, texture->w, texture->h, bpp, Rmask, Gmask,
                                 Bmask, Amask);
        SDL_SetSurfaceColorMod(texture->driverdata, texture->r, texture->g,
                               texture->b);
        SDL_SetSurfaceAlphaMod(texture->driverdata, texture->a);
        SDL_SetSurfaceBlendMode(texture->driverdata, texture->blendMode);
        SDL_SetSurfaceScaleMode(texture->driverdata, texture->scaleMode);

        if (texture->access == SDL_TEXTUREACCESS_STATIC) {
            SDL_SetSurfaceRLE(texture->driverdata, 1);
        }
    }

    if (!texture->driverdata) {
        return -1;
    }
    return 0;
}

static int
SW_QueryTexturePixels(SDL_Renderer * renderer, SDL_Texture * texture,
                      void **pixels, int *pitch)
{
    if (SDL_ISPIXELFORMAT_FOURCC(texture->format)) {
        return SDL_SW_QueryYUVTexturePixels((SDL_SW_YUVTexture *)
                                            texture->driverdata, pixels,
                                            pitch);
    } else {
        SDL_Surface *surface = (SDL_Surface *) texture->driverdata;

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

static int
SW_SetTexturePalette(SDL_Renderer * renderer, SDL_Texture * texture,
                     const SDL_Color * colors, int firstcolor, int ncolors)
{
    if (SDL_ISPIXELFORMAT_FOURCC(texture->format)) {
        SDL_SetError("YUV textures don't have a palette");
        return -1;
    } else {
        SDL_Surface *surface = (SDL_Surface *) texture->driverdata;

        return SDL_SetPaletteColors(surface->format->palette, colors,
                                    firstcolor, ncolors);
    }
}

static int
SW_GetTexturePalette(SDL_Renderer * renderer, SDL_Texture * texture,
                     SDL_Color * colors, int firstcolor, int ncolors)
{
    if (SDL_ISPIXELFORMAT_FOURCC(texture->format)) {
        SDL_SetError("YUV textures don't have a palette");
        return -1;
    } else {
        SDL_Surface *surface = (SDL_Surface *) texture->driverdata;

        SDL_memcpy(colors, &surface->format->palette->colors[firstcolor],
                   ncolors * sizeof(*colors));
        return 0;
    }
}

static int
SW_SetTextureColorMod(SDL_Renderer * renderer, SDL_Texture * texture)
{
    SDL_Surface *surface = (SDL_Surface *) texture->driverdata;
    return SDL_SetSurfaceColorMod(surface, texture->r, texture->g,
                                  texture->b);
}

static int
SW_SetTextureAlphaMod(SDL_Renderer * renderer, SDL_Texture * texture)
{
    SDL_Surface *surface = (SDL_Surface *) texture->driverdata;
    return SDL_SetSurfaceAlphaMod(surface, texture->a);
}

static int
SW_SetTextureBlendMode(SDL_Renderer * renderer, SDL_Texture * texture)
{
    SDL_Surface *surface = (SDL_Surface *) texture->driverdata;
    return SDL_SetSurfaceBlendMode(surface, texture->blendMode);
}

static int
SW_SetTextureScaleMode(SDL_Renderer * renderer, SDL_Texture * texture)
{
    SDL_Surface *surface = (SDL_Surface *) texture->driverdata;
    return SDL_SetSurfaceScaleMode(surface, texture->scaleMode);
}

static int
SW_UpdateTexture(SDL_Renderer * renderer, SDL_Texture * texture,
                 const SDL_Rect * rect, const void *pixels, int pitch)
{
    if (SDL_ISPIXELFORMAT_FOURCC(texture->format)) {
        return SDL_SW_UpdateYUVTexture((SDL_SW_YUVTexture *)
                                       texture->driverdata, rect, pixels,
                                       pitch);
    } else {
        SDL_Surface *surface = (SDL_Surface *) texture->driverdata;
        Uint8 *src, *dst;
        int row;
        size_t length;

        src = (Uint8 *) pixels;
        dst =
            (Uint8 *) surface->pixels + rect->y * surface->pitch +
            rect->x * surface->format->BytesPerPixel;
        length = rect->w * surface->format->BytesPerPixel;
        for (row = 0; row < rect->h; ++row) {
            SDL_memcpy(dst, src, length);
            src += pitch;
            dst += surface->pitch;
        }
        return 0;
    }
}

static int
SW_LockTexture(SDL_Renderer * renderer, SDL_Texture * texture,
               const SDL_Rect * rect, int markDirty, void **pixels,
               int *pitch)
{
    if (SDL_ISPIXELFORMAT_FOURCC(texture->format)) {
        return SDL_SW_LockYUVTexture((SDL_SW_YUVTexture *)
                                     texture->driverdata, rect, markDirty,
                                     pixels, pitch);
    } else {
        SDL_Surface *surface = (SDL_Surface *) texture->driverdata;

        *pixels =
            (void *) ((Uint8 *) surface->pixels + rect->y * surface->pitch +
                      rect->x * surface->format->BytesPerPixel);
        *pitch = surface->pitch;
        return 0;
    }
}

static void
SW_UnlockTexture(SDL_Renderer * renderer, SDL_Texture * texture)
{
    if (SDL_ISPIXELFORMAT_FOURCC(texture->format)) {
        SDL_SW_UnlockYUVTexture((SDL_SW_YUVTexture *) texture->driverdata);
    }
}

static int
SW_RenderPoint(SDL_Renderer * renderer, int x, int y)
{
    SW_RenderData *data = (SW_RenderData *) renderer->driverdata;
    SDL_Rect rect;
    int status;

    rect.x = x;
    rect.y = y;
    rect.w = 1;
    rect.h = 1;

    if (data->renderer->info.flags & SDL_RENDERER_PRESENTCOPY) {
        SDL_AddDirtyRect(&data->dirty, &rect);
    }

    if (data->renderer->LockTexture(data->renderer,
                                    data->texture[data->current_texture],
                                    &rect, 1,
                                    &data->surface.pixels,
                                    &data->surface.pitch) < 0) {
        return -1;
    }

    data->surface.w = 1;
    data->surface.h = 1;
    data->surface.clip_rect.w = 1;
    data->surface.clip_rect.h = 1;

    if (renderer->blendMode == SDL_BLENDMODE_NONE ||
        renderer->blendMode == SDL_BLENDMODE_MASK) {
        Uint32 color =
            SDL_MapRGBA(data->surface.format, renderer->r, renderer->g,
                        renderer->b, renderer->a);

        status = SDL_DrawPoint(&data->surface, 0, 0, color);
    } else {
        status =
            SDL_BlendPoint(&data->surface, 0, 0, renderer->blendMode,
                           renderer->r, renderer->g, renderer->b,
                           renderer->a);
    }

    data->renderer->UnlockTexture(data->renderer,
                                  data->texture[data->current_texture]);
    return status;
}

static int
SW_RenderLine(SDL_Renderer * renderer, int x1, int y1, int x2, int y2)
{
    SW_RenderData *data = (SW_RenderData *) renderer->driverdata;
    SDL_Rect rect;
    int status;

    if (x1 < x2) {
        rect.x = x1;
        rect.w = (x2 - x1) + 1;
        x2 -= x1;
        x1 = 0;
    } else {
        rect.x = x2;
        rect.w = (x1 - x2) + 1;
        x1 -= x2;
        x2 = 0;
    }
    if (y1 < y2) {
        rect.y = y1;
        rect.h = (y2 - y1) + 1;
        y2 -= y1;
        y1 = 0;
    } else {
        rect.y = y2;
        rect.h = (y1 - y2) + 1;
        y1 -= y2;
        y2 = 0;
    }

    if (data->renderer->info.flags & SDL_RENDERER_PRESENTCOPY) {
        SDL_AddDirtyRect(&data->dirty, &rect);
    }

    if (data->renderer->LockTexture(data->renderer,
                                    data->texture[data->current_texture],
                                    &rect, 1,
                                    &data->surface.pixels,
                                    &data->surface.pitch) < 0) {
        return -1;
    }

    data->surface.w = rect.w;
    data->surface.h = rect.h;
    data->surface.clip_rect.w = rect.w;
    data->surface.clip_rect.h = rect.h;

    if (renderer->blendMode == SDL_BLENDMODE_NONE ||
        renderer->blendMode == SDL_BLENDMODE_MASK) {
        Uint32 color =
            SDL_MapRGBA(data->surface.format, renderer->r, renderer->g,
                        renderer->b, renderer->a);

        status = SDL_DrawLine(&data->surface, x1, y1, x2, y2, color);
    } else {
        status =
            SDL_BlendLine(&data->surface, x1, y1, x2, y2, renderer->blendMode,
                          renderer->r, renderer->g, renderer->b, renderer->a);
    }

    data->renderer->UnlockTexture(data->renderer,
                                  data->texture[data->current_texture]);
    return status;
}

static int
SW_RenderFill(SDL_Renderer * renderer, const SDL_Rect * rect)
{
    SW_RenderData *data = (SW_RenderData *) renderer->driverdata;
    SDL_Rect real_rect;
    int status;

    if (data->renderer->info.flags & SDL_RENDERER_PRESENTCOPY) {
        SDL_AddDirtyRect(&data->dirty, rect);
    }

    if (data->renderer->LockTexture(data->renderer,
                                    data->texture[data->current_texture],
                                    rect, 1, &data->surface.pixels,
                                    &data->surface.pitch) < 0) {
        return -1;
    }

    data->surface.w = rect->w;
    data->surface.h = rect->h;
    data->surface.clip_rect.w = rect->w;
    data->surface.clip_rect.h = rect->h;
    real_rect = data->surface.clip_rect;

    if (renderer->blendMode == SDL_BLENDMODE_NONE) {
        Uint32 color =
            SDL_MapRGBA(data->surface.format, renderer->r, renderer->g,
                        renderer->b, renderer->a);

        status = SDL_FillRect(&data->surface, &real_rect, color);
    } else {
        status =
            SDL_BlendRect(&data->surface, &real_rect, renderer->blendMode,
                          renderer->r, renderer->g, renderer->b, renderer->a);
    }

    data->renderer->UnlockTexture(data->renderer,
                                  data->texture[data->current_texture]);
    return status;
}

static int
SW_RenderCopy(SDL_Renderer * renderer, SDL_Texture * texture,
              const SDL_Rect * srcrect, const SDL_Rect * dstrect)
{
    SW_RenderData *data = (SW_RenderData *) renderer->driverdata;
    SDL_Window *window = SDL_GetWindowFromID(renderer->window);
    int status;

    if (data->renderer->info.flags & SDL_RENDERER_PRESENTCOPY) {
        SDL_AddDirtyRect(&data->dirty, dstrect);
    }

    if (data->renderer->LockTexture(data->renderer,
                                    data->texture[data->current_texture],
                                    dstrect, 1, &data->surface.pixels,
                                    &data->surface.pitch) < 0) {
        return -1;
    }

    if (SDL_ISPIXELFORMAT_FOURCC(texture->format)) {
        status =
            SDL_SW_CopyYUVToRGB((SDL_SW_YUVTexture *) texture->driverdata,
                                srcrect, data->format, dstrect->w, dstrect->h,
                                data->surface.pixels, data->surface.pitch);
    } else {
        SDL_Surface *surface = (SDL_Surface *) texture->driverdata;
        SDL_Rect real_srcrect = *srcrect;
        SDL_Rect real_dstrect;

        data->surface.w = dstrect->w;
        data->surface.h = dstrect->h;
        data->surface.clip_rect.w = dstrect->w;
        data->surface.clip_rect.h = dstrect->h;
        real_dstrect = data->surface.clip_rect;

        status =
            SDL_LowerBlit(surface, &real_srcrect, &data->surface,
                          &real_dstrect);
    }
    data->renderer->UnlockTexture(data->renderer,
                                  data->texture[data->current_texture]);
    return status;
}

static int
SW_RenderReadPixels(SDL_Renderer * renderer, const SDL_Rect * rect,
                    Uint32 format, void * pixels, int pitch)
{
    SW_RenderData *data = (SW_RenderData *) renderer->driverdata;

    if (data->renderer->LockTexture(data->renderer,
                                    data->texture[data->current_texture],
                                    rect, 0, &data->surface.pixels,
                                    &data->surface.pitch) < 0) {
        return -1;
    }

    SDL_ConvertPixels(rect->w, rect->h,
                      data->format, data->surface.pixels, data->surface.pitch,
                      format, pixels, pitch);

    data->renderer->UnlockTexture(data->renderer,
                                  data->texture[data->current_texture]);
    return 0;
}

static int
SW_RenderWritePixels(SDL_Renderer * renderer, const SDL_Rect * rect,
                     Uint32 format, const void * pixels, int pitch)
{
    SW_RenderData *data = (SW_RenderData *) renderer->driverdata;

    if (data->renderer->info.flags & SDL_RENDERER_PRESENTCOPY) {
        SDL_AddDirtyRect(&data->dirty, rect);
    }

    if (data->renderer->LockTexture(data->renderer,
                                    data->texture[data->current_texture],
                                    rect, 1, &data->surface.pixels,
                                    &data->surface.pitch) < 0) {
        return -1;
    }

    SDL_ConvertPixels(rect->w, rect->h, format, pixels, pitch,
                      data->format, data->surface.pixels, data->surface.pitch);

    data->renderer->UnlockTexture(data->renderer,
                                  data->texture[data->current_texture]);
    return 0;
}

static void
SW_RenderPresent(SDL_Renderer * renderer)
{
    SW_RenderData *data = (SW_RenderData *) renderer->driverdata;
    SDL_Texture *texture = data->texture[data->current_texture];

    /* Send the data to the display */
    if (data->renderer->info.flags & SDL_RENDERER_PRESENTCOPY) {
        SDL_DirtyRect *dirty;
        for (dirty = data->dirty.list; dirty; dirty = dirty->next) {
            data->renderer->RenderCopy(data->renderer, texture, &dirty->rect,
                                       &dirty->rect);
        }
        SDL_ClearDirtyRects(&data->dirty);
    } else {
        SDL_Rect rect;
        rect.x = 0;
        rect.y = 0;
        rect.w = texture->w;
        rect.h = texture->h;
        data->renderer->RenderCopy(data->renderer, texture, &rect, &rect);
    }
    data->renderer->RenderPresent(data->renderer);

    /* Update the flipping chain, if any */
    if (renderer->info.flags & SDL_RENDERER_PRESENTFLIP2) {
        data->current_texture = (data->current_texture + 1) % 2;
    } else if (renderer->info.flags & SDL_RENDERER_PRESENTFLIP3) {
        data->current_texture = (data->current_texture + 1) % 3;
    }
}

static void
SW_DestroyTexture(SDL_Renderer * renderer, SDL_Texture * texture)
{
    if (SDL_ISPIXELFORMAT_FOURCC(texture->format)) {
        SDL_SW_DestroyYUVTexture((SDL_SW_YUVTexture *) texture->driverdata);
    } else {
        SDL_Surface *surface = (SDL_Surface *) texture->driverdata;

        SDL_FreeSurface(surface);
    }
}

static void
SW_DestroyRenderer(SDL_Renderer * renderer)
{
    SW_RenderData *data = (SW_RenderData *) renderer->driverdata;
    SDL_Window *window = SDL_GetWindowFromID(renderer->window);
    SDL_VideoDisplay *display = SDL_GetDisplayFromWindow(window);
    int i;

    if (data) {
        for (i = 0; i < SDL_arraysize(data->texture); ++i) {
            if (data->texture[i]) {
                DestroyTexture(data->renderer, data->texture[i]);
            }
        }
        if (data->surface.format) {
            SDL_SetSurfacePalette(&data->surface, NULL);
            SDL_FreeFormat(data->surface.format);
        }
        if (display->palette) {
            SDL_DelPaletteWatch(display->palette, DisplayPaletteChanged,
                                data);
        }
        if (data->renderer) {
            data->renderer->DestroyRenderer(data->renderer);
        }
        SDL_FreeDirtyRects(&data->dirty);
        SDL_free(data);
    }
    SDL_free(renderer);
}

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