+boolean DrawingOnBackground(int x, int y)
+{
+ return (CheckDrawingArea(x, y, 1, 1, gfx.background_bitmap_mask) &&
+ CheckDrawingArea(x, y, 1, 1, gfx.draw_background_mask));
+}
+
+static boolean InClippedRectangle(Bitmap *bitmap, int *x, int *y,
+ int *width, int *height, boolean is_dest)
+{
+ int clip_x, clip_y, clip_width, clip_height;
+
+ if (gfx.clipping_enabled && is_dest) // only clip destination bitmap
+ {
+ clip_x = MIN(MAX(0, gfx.clip_x), bitmap->width);
+ clip_y = MIN(MAX(0, gfx.clip_y), bitmap->height);
+ clip_width = MIN(MAX(0, gfx.clip_width), bitmap->width - clip_x);
+ clip_height = MIN(MAX(0, gfx.clip_height), bitmap->height - clip_y);
+ }
+ else
+ {
+ clip_x = 0;
+ clip_y = 0;
+ clip_width = bitmap->width;
+ clip_height = bitmap->height;
+ }
+
+ // skip if rectangle completely outside bitmap
+
+ if (*x + *width <= clip_x ||
+ *y + *height <= clip_y ||
+ *x >= clip_x + clip_width ||
+ *y >= clip_y + clip_height)
+ return FALSE;
+
+ // clip if rectangle overlaps bitmap
+
+ if (*x < clip_x)
+ {
+ *width -= clip_x - *x;
+ *x = clip_x;
+ }
+ else if (*x + *width > clip_x + clip_width)
+ {
+ *width = clip_x + clip_width - *x;
+ }
+
+ if (*y < clip_y)
+ {
+ *height -= clip_y - *y;
+ *y = clip_y;
+ }
+ else if (*y + *height > clip_y + clip_height)
+ {
+ *height = clip_y + clip_height - *y;
+ }
+
+ return TRUE;
+}
+
+void BlitBitmap(Bitmap *src_bitmap, Bitmap *dst_bitmap,
+ int src_x, int src_y, int width, int height,
+ int dst_x, int dst_y)
+{
+ int dst_x_unclipped = dst_x;
+ int dst_y_unclipped = dst_y;
+
+ if (program.headless)
+ return;
+
+ if (src_bitmap == NULL || dst_bitmap == NULL)
+ return;
+
+ if (DrawingDeactivated(dst_x, dst_y, width, height))
+ return;
+
+ if (!InClippedRectangle(src_bitmap, &src_x, &src_y, &width, &height, FALSE) ||
+ !InClippedRectangle(dst_bitmap, &dst_x, &dst_y, &width, &height, TRUE))
+ return;
+
+ // source x/y might need adjustment if destination x/y was clipped top/left
+ src_x += dst_x - dst_x_unclipped;
+ src_y += dst_y - dst_y_unclipped;
+
+#if defined(TARGET_SDL2)
+ // !!! 2013-12-11: An "old friend" is back. Same bug in SDL2 2.0.1 !!!
+ // !!! 2009-03-30: Fixed by using self-compiled, patched SDL.dll !!!
+ /* (This bug still exists in the actual (as of 2009-06-15) version 1.2.13,
+ but is already fixed in SVN and should therefore finally be fixed with
+ the next official SDL release, which is probably version 1.2.14.) */
+ // !!! 2009-03-24: It seems that this problem still exists in 1.2.12 !!!
+
+ if (src_bitmap == dst_bitmap)
+ {
+ // needed when blitting directly to same bitmap -- should not be needed with
+ // recent SDL libraries, but apparently does not work in 1.2.11 directly
+
+ static Bitmap *tmp_bitmap = NULL;
+ static int tmp_bitmap_xsize = 0;
+ static int tmp_bitmap_ysize = 0;
+
+ // start with largest static bitmaps for initial bitmap size ...
+ if (tmp_bitmap_xsize == 0 && tmp_bitmap_ysize == 0)
+ {
+ tmp_bitmap_xsize = MAX(gfx.win_xsize, gfx.scrollbuffer_width);
+ tmp_bitmap_ysize = MAX(gfx.win_ysize, gfx.scrollbuffer_height);
+ }
+
+ // ... and allow for later re-adjustments due to custom artwork bitmaps
+ if (src_bitmap->width > tmp_bitmap_xsize ||
+ src_bitmap->height > tmp_bitmap_ysize)
+ {
+ tmp_bitmap_xsize = MAX(tmp_bitmap_xsize, src_bitmap->width);
+ tmp_bitmap_ysize = MAX(tmp_bitmap_ysize, src_bitmap->height);
+
+ FreeBitmap(tmp_bitmap);
+
+ tmp_bitmap = NULL;
+ }
+
+ if (tmp_bitmap == NULL)
+ tmp_bitmap = CreateBitmap(tmp_bitmap_xsize, tmp_bitmap_ysize,
+ DEFAULT_DEPTH);
+
+ sysCopyArea(src_bitmap, tmp_bitmap,
+ src_x, src_y, width, height, dst_x, dst_y, BLIT_OPAQUE);
+ sysCopyArea(tmp_bitmap, dst_bitmap,
+ dst_x, dst_y, width, height, dst_x, dst_y, BLIT_OPAQUE);
+
+ return;
+ }
+#endif
+
+ sysCopyArea(src_bitmap, dst_bitmap,
+ src_x, src_y, width, height, dst_x, dst_y, BLIT_OPAQUE);
+}
+
+void BlitBitmapTiled(Bitmap *src_bitmap, Bitmap *dst_bitmap,
+ int src_x, int src_y, int src_width, int src_height,
+ int dst_x, int dst_y, int dst_width, int dst_height)
+{
+ int src_xsize = (src_width == 0 ? src_bitmap->width : src_width);
+ int src_ysize = (src_height == 0 ? src_bitmap->height : src_height);
+ int dst_xsize = dst_width;
+ int dst_ysize = dst_height;
+ int src_xsteps = (dst_xsize + src_xsize - 1) / src_xsize;
+ int src_ysteps = (dst_ysize + src_ysize - 1) / src_ysize;
+ int x, y;
+
+ for (y = 0; y < src_ysteps; y++)
+ {
+ for (x = 0; x < src_xsteps; x++)
+ {
+ int draw_x = dst_x + x * src_xsize;
+ int draw_y = dst_y + y * src_ysize;
+ int draw_xsize = MIN(src_xsize, dst_xsize - x * src_xsize);
+ int draw_ysize = MIN(src_ysize, dst_ysize - y * src_ysize);
+
+ BlitBitmap(src_bitmap, dst_bitmap, src_x, src_y, draw_xsize, draw_ysize,
+ draw_x, draw_y);
+ }
+ }