The code in UpperBlit performs rectangle validation. This is a great piece of
code, even if – and because, like many gemms in SDL – it looks simple.
Changing a very few lines would allow gurus to use it – but it should still
stay semi-private and undocumented.
Here is my patch (really: 5 lines added.) Will Sam take it?
— SDL_surface.c Tue Mar 16 11:07:32 2004
+++ SDL_surface_new.c Sun Aug 01 07:40:53 2004
@@ -432,8 +432,9 @@
}
-int SDL_UpperBlit (SDL_Surface *src, SDL_Rect *srcrect,
-
SDL_Surface *dst, SDL_Rect *dstrect)
+int SDL_ValidateRect (SDL_Surface *src, SDL_Rect *srcrect,
-
SDL_Surface *dst, SDL_Rect *dstrect, -
SDL_Rect *srcvalidrect)
{
SDL_Rect fulldst;
int srcx, srcy, w, h;
@@ -513,16 +514,22 @@
}
if(w > 0 && h > 0) {
-
SDL_Rect sr; -
sr.x = srcx; -
sr.y = srcy; -
sr.w = dstrect->w = w; -
sr.h = dstrect->h = h; -
return SDL_LowerBlit(src, &sr, dst, dstrect);
-
srcvalidrect->x = srcx; -
srcvalidrect->y = srcy; -
srcvalidrect->w = dstrect->w = w; -
srcvalidrect->h = dstrect->h = h; -
}return 1;
dstrect->w = dstrect->h = 0;
return 0;
}+
+int SDL_UpperBlit (SDL_Surface *src, SDL_Rect *srcrect, -
SDL_Surface *dst, SDL_Rect *dstrect)
+{
- SDL_Rect srcvalidrect;
- if (SDL_ValidateRect(src, srcrect, dst, dstrect, &srcvalidrect))
-
return SDL_LowerBlit(src, &srcvalidrect, dst, dstrect); - return 0;
+}
static int SDL_FillRect1(SDL_Surface *dst, SDL_Rect *dstrect, Uint32 color)
{
