+inline Pixel SDLGetPixel(Bitmap *dst_bitmap, int x, int y)
+{
+ SDL_Surface *surface = dst_bitmap->surface;
+
+#ifdef FULLSCREEN_BUG
+ if (dst_bitmap == backbuffer || dst_bitmap == window)
+ {
+ x += video_xoffset;
+ y += video_yoffset;
+ }
+#endif
+
+ switch (surface->format->BytesPerPixel)
+ {
+ case 1: /* assuming 8-bpp */
+ {
+ return *((Uint8 *)surface->pixels + y * surface->pitch + x);
+ }
+ break;
+
+ case 2: /* probably 15-bpp or 16-bpp */
+ {
+ return *((Uint16 *)surface->pixels + y * surface->pitch / 2 + x);
+ }
+ break;
+
+ case 3: /* slow 24-bpp mode; usually not used */
+ {
+ /* does this work? */
+ Uint8 *pix = (Uint8 *)surface->pixels + y * surface->pitch + x * 3;
+ Uint32 color = 0;
+ int shift;
+
+ shift = surface->format->Rshift;
+ color |= *(pix + shift / 8) >> shift;
+ shift = surface->format->Gshift;
+ color |= *(pix + shift / 8) >> shift;
+ shift = surface->format->Bshift;
+ color |= *(pix + shift / 8) >> shift;
+
+ return color;
+ }
+ break;
+
+ case 4: /* probably 32-bpp */
+ {
+ return *((Uint32 *)surface->pixels + y * surface->pitch / 4 + x);
+ }
+ break;
+ }
+
+ return 0;
+}
+
+
+/* ========================================================================= */
+/* The following functions have been taken from the SGE library */
+/* (SDL Graphics Extension Library) by Anders Lindström */
+/* http://www.etek.chalmers.se/~e8cal1/sge/index.html */
+/* ========================================================================= */
+
+void _PutPixel(SDL_Surface *surface, Sint16 x, Sint16 y, Uint32 color)
+{
+ if (x >= 0 && x <= surface->w - 1 && y >= 0 && y <= surface->h - 1)
+ {
+ switch (surface->format->BytesPerPixel)
+ {
+ case 1:
+ {
+ /* Assuming 8-bpp */
+ *((Uint8 *)surface->pixels + y*surface->pitch + x) = color;
+ }
+ break;
+
+ case 2:
+ {
+ /* Probably 15-bpp or 16-bpp */
+ *((Uint16 *)surface->pixels + y*surface->pitch/2 + x) = color;
+ }
+ break;
+
+ case 3:
+ {
+ /* Slow 24-bpp mode, usually not used */
+ Uint8 *pix;
+ int shift;
+
+ /* Gack - slow, but endian correct */
+ pix = (Uint8 *)surface->pixels + y * surface->pitch + x*3;
+ shift = surface->format->Rshift;
+ *(pix+shift/8) = color>>shift;
+ shift = surface->format->Gshift;
+ *(pix+shift/8) = color>>shift;
+ shift = surface->format->Bshift;
+ *(pix+shift/8) = color>>shift;
+ }
+ break;
+
+ case 4:
+ {
+ /* Probably 32-bpp */
+ *((Uint32 *)surface->pixels + y*surface->pitch/4 + x) = color;
+ }
+ break;
+ }
+ }
+}
+
+void _PutPixelRGB(SDL_Surface *surface, Sint16 x, Sint16 y,
+ Uint8 R, Uint8 G, Uint8 B)
+{
+ _PutPixel(surface, x, y, SDL_MapRGB(surface->format, R, G, B));
+}
+
+void _PutPixel8(SDL_Surface *surface, Sint16 x, Sint16 y, Uint32 color)
+{
+ *((Uint8 *)surface->pixels + y*surface->pitch + x) = color;
+}
+
+void _PutPixel16(SDL_Surface *surface, Sint16 x, Sint16 y, Uint32 color)
+{
+ *((Uint16 *)surface->pixels + y*surface->pitch/2 + x) = color;
+}
+
+void _PutPixel24(SDL_Surface *surface, Sint16 x, Sint16 y, Uint32 color)
+{
+ Uint8 *pix;
+ int shift;
+
+ /* Gack - slow, but endian correct */
+ pix = (Uint8 *)surface->pixels + y * surface->pitch + x*3;
+ shift = surface->format->Rshift;
+ *(pix+shift/8) = color>>shift;
+ shift = surface->format->Gshift;
+ *(pix+shift/8) = color>>shift;
+ shift = surface->format->Bshift;
+ *(pix+shift/8) = color>>shift;
+}
+
+void _PutPixel32(SDL_Surface *surface, Sint16 x, Sint16 y, Uint32 color)
+{
+ *((Uint32 *)surface->pixels + y*surface->pitch/4 + x) = color;
+}
+
+void _PutPixelX(SDL_Surface *dest,Sint16 x,Sint16 y,Uint32 color)
+{
+ switch (dest->format->BytesPerPixel)
+ {
+ case 1:
+ *((Uint8 *)dest->pixels + y*dest->pitch + x) = color;
+ break;
+
+ case 2:
+ *((Uint16 *)dest->pixels + y*dest->pitch/2 + x) = color;
+ break;
+
+ case 3:
+ _PutPixel24(dest,x,y,color);
+ break;
+
+ case 4:
+ *((Uint32 *)dest->pixels + y*dest->pitch/4 + x) = color;
+ break;
+ }
+}
+
+void sge_PutPixel(SDL_Surface *surface, Sint16 x, Sint16 y, Uint32 color)
+{
+ if (SDL_MUSTLOCK(surface))
+ {
+ if (SDL_LockSurface(surface) < 0)
+ {
+ return;
+ }
+ }
+
+ _PutPixel(surface, x, y, color);
+
+ if (SDL_MUSTLOCK(surface))
+ {
+ SDL_UnlockSurface(surface);
+ }
+}
+
+void sge_PutPixelRGB(SDL_Surface *surface, Sint16 x, Sint16 y,
+ Uint8 R, Uint8 G, Uint8 B)
+{
+ sge_PutPixel(surface, x, y, SDL_MapRGB(surface->format, R, G, B));
+}
+
+Sint32 sge_CalcYPitch(SDL_Surface *dest, Sint16 y)
+{
+ if (y >= 0 && y <= dest->h - 1)
+ {
+ switch (dest->format->BytesPerPixel)
+ {
+ case 1:
+ return y*dest->pitch;
+ break;
+
+ case 2:
+ return y*dest->pitch/2;
+ break;
+
+ case 3:
+ return y*dest->pitch;
+ break;
+
+ case 4:
+ return y*dest->pitch/4;
+ break;
+ }
+ }
+
+ return -1;
+}
+
+void sge_pPutPixel(SDL_Surface *surface, Sint16 x, Sint32 ypitch, Uint32 color)
+{
+ if (x >= 0 && x <= surface->w - 1 && ypitch >= 0)
+ {
+ switch (surface->format->BytesPerPixel)
+ {
+ case 1:
+ {
+ /* Assuming 8-bpp */
+ *((Uint8 *)surface->pixels + ypitch + x) = color;
+ }
+ break;
+
+ case 2:
+ {
+ /* Probably 15-bpp or 16-bpp */
+ *((Uint16 *)surface->pixels + ypitch + x) = color;
+ }
+ break;
+
+ case 3:
+ {
+ /* Slow 24-bpp mode, usually not used */
+ Uint8 *pix;
+ int shift;
+
+ /* Gack - slow, but endian correct */
+ pix = (Uint8 *)surface->pixels + ypitch + x*3;
+ shift = surface->format->Rshift;
+ *(pix+shift/8) = color>>shift;
+ shift = surface->format->Gshift;
+ *(pix+shift/8) = color>>shift;
+ shift = surface->format->Bshift;
+ *(pix+shift/8) = color>>shift;
+ }
+ break;
+
+ case 4:
+ {
+ /* Probably 32-bpp */
+ *((Uint32 *)surface->pixels + ypitch + x) = color;
+ }
+ break;
+ }
+ }
+}
+
+void sge_HLine(SDL_Surface *Surface, Sint16 x1, Sint16 x2, Sint16 y,
+ Uint32 Color)
+{
+ SDL_Rect l;
+
+ if (SDL_MUSTLOCK(Surface))
+ {
+ if (SDL_LockSurface(Surface) < 0)
+ {
+ return;
+ }
+ }
+
+ if (x1 > x2)
+ {
+ Sint16 tmp = x1;
+ x1 = x2;
+ x2 = tmp;
+ }
+
+ /* Do the clipping */
+ if (y < 0 || y > Surface->h - 1 || x1 > Surface->w - 1 || x2 < 0)
+ return;
+ if (x1 < 0)
+ x1 = 0;
+ if (x2 > Surface->w - 1)
+ x2 = Surface->w - 1;
+
+ l.x = x1;
+ l.y = y;
+ l.w = x2 - x1 + 1;
+ l.h = 1;
+
+ SDL_FillRect(Surface, &l, Color);
+
+ if (SDL_MUSTLOCK(Surface))
+ {
+ SDL_UnlockSurface(Surface);
+ }
+}
+
+void sge_HLineRGB(SDL_Surface *Surface, Sint16 x1, Sint16 x2, Sint16 y,
+ Uint8 R, Uint8 G, Uint8 B)
+{
+ sge_HLine(Surface, x1, x2, y, SDL_MapRGB(Surface->format, R, G, B));
+}
+
+void _HLine(SDL_Surface *Surface, Sint16 x1, Sint16 x2, Sint16 y, Uint32 Color)
+{
+ SDL_Rect l;
+
+ if (x1 > x2)
+ {
+ Sint16 tmp = x1;
+ x1 = x2;
+ x2 = tmp;
+ }
+
+ /* Do the clipping */
+ if (y < 0 || y > Surface->h - 1 || x1 > Surface->w - 1 || x2 < 0)
+ return;
+ if (x1 < 0)
+ x1 = 0;
+ if (x2 > Surface->w - 1)
+ x2 = Surface->w - 1;
+
+ l.x = x1;
+ l.y = y;
+ l.w = x2 - x1 + 1;
+ l.h = 1;
+
+ SDL_FillRect(Surface, &l, Color);
+}
+
+void sge_VLine(SDL_Surface *Surface, Sint16 x, Sint16 y1, Sint16 y2,
+ Uint32 Color)
+{
+ SDL_Rect l;
+
+ if (SDL_MUSTLOCK(Surface))
+ {
+ if (SDL_LockSurface(Surface) < 0)
+ {
+ return;
+ }
+ }
+
+ if (y1 > y2)
+ {
+ Sint16 tmp = y1;
+ y1 = y2;
+ y2 = tmp;
+ }
+
+ /* Do the clipping */
+ if (x < 0 || x > Surface->w - 1 || y1 > Surface->h - 1 || y2 < 0)
+ return;
+ if (y1 < 0)
+ y1 = 0;
+ if (y2 > Surface->h - 1)
+ y2 = Surface->h - 1;
+
+ l.x = x;
+ l.y = y1;
+ l.w = 1;
+ l.h = y2 - y1 + 1;
+
+ SDL_FillRect(Surface, &l, Color);
+
+ if (SDL_MUSTLOCK(Surface))
+ {
+ SDL_UnlockSurface(Surface);
+ }
+}
+
+void sge_VLineRGB(SDL_Surface *Surface, Sint16 x, Sint16 y1, Sint16 y2,
+ Uint8 R, Uint8 G, Uint8 B)
+{
+ sge_VLine(Surface, x, y1, y2, SDL_MapRGB(Surface->format, R, G, B));
+}
+
+void _VLine(SDL_Surface *Surface, Sint16 x, Sint16 y1, Sint16 y2, Uint32 Color)
+{
+ SDL_Rect l;
+
+ if (y1 > y2)
+ {
+ Sint16 tmp = y1;
+ y1 = y2;
+ y2 = tmp;
+ }
+
+ /* Do the clipping */
+ if (x < 0 || x > Surface->w - 1 || y1 > Surface->h - 1 || y2 < 0)
+ return;
+ if (y1 < 0)
+ y1 = 0;
+ if (y2 > Surface->h - 1)
+ y2 = Surface->h - 1;
+
+ l.x = x;
+ l.y = y1;
+ l.w = 1;
+ l.h = y2 - y1 + 1;
+
+ SDL_FillRect(Surface, &l, Color);
+}
+
+void sge_DoLine(SDL_Surface *Surface, Sint16 x1, Sint16 y1,
+ Sint16 x2, Sint16 y2, Uint32 Color,
+ void Callback(SDL_Surface *Surf, Sint16 X, Sint16 Y,
+ Uint32 Color))
+{
+ Sint16 dx, dy, sdx, sdy, x, y, px, py;
+
+ dx = x2 - x1;
+ dy = y2 - y1;
+
+ sdx = (dx < 0) ? -1 : 1;
+ sdy = (dy < 0) ? -1 : 1;
+
+ dx = sdx * dx + 1;
+ dy = sdy * dy + 1;
+
+ x = y = 0;
+
+ px = x1;
+ py = y1;
+
+ if (dx >= dy)
+ {
+ for (x = 0; x < dx; x++)
+ {
+ Callback(Surface, px, py, Color);
+
+ y += dy;
+ if (y >= dx)
+ {
+ y -= dx;
+ py += sdy;
+ }
+
+ px += sdx;
+ }
+ }
+ else
+ {
+ for (y = 0; y < dy; y++)
+ {
+ Callback(Surface, px, py, Color);
+
+ x += dx;
+ if (x >= dy)
+ {
+ x -= dy;
+ px += sdx;
+ }
+
+ py += sdy;
+ }
+ }
+}
+
+void sge_DoLineRGB(SDL_Surface *Surface, Sint16 X1, Sint16 Y1,
+ Sint16 X2, Sint16 Y2, Uint8 R, Uint8 G, Uint8 B,
+ void Callback(SDL_Surface *Surf, Sint16 X, Sint16 Y,
+ Uint32 Color))
+{
+ sge_DoLine(Surface, X1, Y1, X2, Y2,
+ SDL_MapRGB(Surface->format, R, G, B), Callback);
+}
+
+void sge_Line(SDL_Surface *Surface, Sint16 x1, Sint16 y1, Sint16 x2, Sint16 y2,
+ Uint32 Color)
+{
+ if (SDL_MUSTLOCK(Surface))
+ {
+ if (SDL_LockSurface(Surface) < 0)
+ return;
+ }
+
+ /* Draw the line */
+ sge_DoLine(Surface, x1, y1, x2, y2, Color, _PutPixel);
+
+ /* unlock the display */
+ if (SDL_MUSTLOCK(Surface))
+ {
+ SDL_UnlockSurface(Surface);
+ }
+}
+
+void sge_LineRGB(SDL_Surface *Surface, Sint16 x1, Sint16 y1, Sint16 x2,
+ Sint16 y2, Uint8 R, Uint8 G, Uint8 B)
+{
+ sge_Line(Surface, x1, y1, x2, y2, SDL_MapRGB(Surface->format, R, G, B));
+}
+
+Bitmap *SDLLoadImage(char *filename)
+{
+ Bitmap *new_bitmap = CreateBitmapStruct();
+ SDL_Surface *sdl_image_tmp;
+
+ /* load image to temporary surface */
+ if ((sdl_image_tmp = IMG_Load(filename)) == NULL)
+ {
+ SetError("IMG_Load(): %s", SDL_GetError());
+ return NULL;
+ }
+
+ /* create native non-transparent surface for current image */
+ if ((new_bitmap->surface = SDL_DisplayFormat(sdl_image_tmp)) == NULL)
+ {
+ SetError("SDL_DisplayFormat(): %s", SDL_GetError());
+ return NULL;
+ }
+
+ /* create native transparent surface for current image */
+ SDL_SetColorKey(sdl_image_tmp, SDL_SRCCOLORKEY,
+ SDL_MapRGB(sdl_image_tmp->format, 0x00, 0x00, 0x00));
+ if ((new_bitmap->surface_masked = SDL_DisplayFormat(sdl_image_tmp)) == NULL)
+ {
+ SetError("SDL_DisplayFormat(): %s", SDL_GetError());
+ return NULL;
+ }
+
+ /* free temporary surface */
+ SDL_FreeSurface(sdl_image_tmp);
+
+ new_bitmap->width = new_bitmap->surface->w;
+ new_bitmap->height = new_bitmap->surface->h;
+
+ return new_bitmap;
+}
+
+
+/* ========================================================================= */
+/* audio functions */
+/* ========================================================================= */
+
+inline void SDLOpenAudio(void)
+{
+ if (SDL_InitSubSystem(SDL_INIT_AUDIO) < 0)
+ {
+ Error(ERR_WARN, "SDL_InitSubSystem() failed: %s", SDL_GetError());
+ return;
+ }
+
+ if (Mix_OpenAudio(DEFAULT_AUDIO_SAMPLE_RATE, AUDIO_S16,
+ AUDIO_STEREO_CHANNELS,
+ DEFAULT_AUDIO_FRAGMENT_SIZE) < 0)