diff options
| -rw-r--r-- | sdl.cpp | 12 |
1 files changed, 7 insertions, 5 deletions
@@ -467,14 +467,16 @@ void OSystem_SDL::add_dirty_rect(int x, int y, int w, int h) { #define DOLINE(x) a ^= ((uint32*)buf)[0+(x)*(SCREEN_WIDTH/4)]; b ^= ((uint32*)buf)[1+(x)*(SCREEN_WIDTH/4)] void OSystem_SDL::mk_checksums(const byte *buf) { uint32 *sums = dirty_checksums; - int x,y; + uint x,y; + const uint last_x = (uint)SCREEN_WIDTH/8; + const uint last_y = (uint)SCREEN_HEIGHT/8; /* the 8x8 blocks in buf are enumerated starting in the top left corner and * reading each line at a time from left to right */ - for(y=0; y!=SCREEN_HEIGHT/8; y++,buf+=SCREEN_WIDTH*(8-1)) - for(x=0; x!=SCREEN_WIDTH/8; x++,buf+=8) { - int32 a = x; - int32 b = y; + for(y=0; y != last_y; y++, buf+=SCREEN_WIDTH*(8-1)) + for(x=0; x != last_x; x++, buf+=8) { + uint32 a = x; + uint32 b = y; DOLINE(0); ROL(a,13); ROL(b,11); DOLINE(2); ROL(a,13); ROL(b,11); |