#ifdef __POWERPC__

	// PPC appears to handle updating of rectangles right

	{

		uint num_dirty_rects;

		uint length_drawn;

		uint left;

		uint i;

		num_dirty_rects = _cocoa_video_data.num_dirty_rects;

		/* Check if we need to do anything */

		if (num_dirty_rects == 0 ) return;

		if (num_dirty_rects >= MAX_DIRTY_RECTS) {

			num_dirty_rects = 1;

			_cocoa_video_data.dirty_rects[0].left = 0;

			_cocoa_video_data.dirty_rects[0].top = 0;

			_cocoa_video_data.dirty_rects[0].right = _cocoa_video_data.width;

			_cocoa_video_data.dirty_rects[0].bottom = _cocoa_video_data.height;

		}

		QZ_WaitForVerticalBlank();

		/* Build the region of dirty rectangles */

		for (i = 0; i < num_dirty_rects; i++) {

			y = _cocoa_video_data.dirty_rects[i].top;

			left = _cocoa_video_data.dirty_rects[i].left;

			length_drawn = _cocoa_video_data.dirty_rects[i].right - left + 1;

			height = _cocoa_video_data.dirty_rects[i].bottom;

			for (; y <= height; y++) memcpy(dst + y * pitch + left, src + y * width +left, length_drawn);

		}

		_cocoa_video_data.num_dirty_rects = 0;

#else

	// it appears that Intel based macs didn't like to only update parts of the screen at a time, so they still update everything at each frame

	// we need to switch to use Quartz exclusively (no QuickDraw commands at all) to fix this

	// to use Quartz exclusively, we should use 16 or 32 bit graphics since 8 bit coloured graphic support sucks

	height  = _cocoa_video_data.height;

	QZ_WaitForVerticalBlank();

	for (y = 0; y < height; y++) memcpy(dst + y * pitch, src + y * width, width);

#endif