static void
update_rect(SDL_Rect *fill, int x, int y, int w, int h, int idx, int level)
{
SDL_Rect r = {x, y, w, h};
int nw = w / 2;
int nh = h / 2;
int area = 0;
assert((unsigned)idx < dirty_tree_length);
/* PRUNING: see if already dirty */
if (dirty_tree[idx])
return;
/* PRUNING: check if covered area > AV_DTREE_FILL_RATIO */
area = intersect_area(fill, &r);
if (area == 0)
return;
else if (level == AV_DTREE_DEPTH
|| area > AV_DTREE_FILL_RATIO * h * w)
{
dirty_tree[idx] = 1;
return;
}
idx *= 4;
level += 1;
update_rect(fill, x, y, nw, nh, idx + 1, level);
update_rect(fill, x + nw, y, w - nw, nh, idx + 2, level);
update_rect(fill, x, y + nh, nw, h - nh, idx + 3, level);
update_rect(fill, x + nw, y + nh, w - nw, h - nh, idx + 4, level);
}
void rsView::intersectClipRect(int32_t x, int32_t y, int32_t dx, int32_t dy)
{
intersect_area(cliprect.x, cliprect.y, cliprect.dx, cliprect.dy, x, y, dx, dy);
}
void rsView::intersectViewport(int32_t x, int32_t y, int32_t dx, int32_t dy)
{
intersect_area(viewport.x, viewport.y, viewport.dx, viewport.dy, x, y, dx, dy);
}