diff options
| -rw-r--r-- | scumm/gfx.cpp | 8 |
1 files changed, 6 insertions, 2 deletions
diff --git a/scumm/gfx.cpp b/scumm/gfx.cpp index 9131d50cf3..6451860a26 100644 --- a/scumm/gfx.cpp +++ b/scumm/gfx.cpp @@ -844,9 +844,13 @@ void Scumm::restoreBG(ScummVM::Rect rect, byte backColor) { blit(backbuff, bgbak, width, height); if (vs->number == 0 && _charset->_hasMask && height) { byte *mask; - int mask_width = (width >> 3); + // Note: At first sight it may look as if this could + // be optimized to (rect.right - rect.left) >> 3 and + // thus to width >> 3, but that's not the case since + // we are dealing with integer math here. + int mask_width = (rect.right >> 3) - (rect.left >> 3); - if (width & 0x07) + if (rect.right & 0x07) mask_width++; mask = getResourceAddress(rtBuffer, 9) + rect.top * gdi._numStrips + (rect.left >> 3) + _screenStartStrip; |