Function DrawOverlappedWindow

src/window.cpp:885–937

* Generate repaint events for the visible part of window w within the rectangle. * * The function goes recursively upwards in the window stack, and splits the rectangle * into multiple pieces at the window edges, so obscured parts are not redrawn. * * @param w Window that needs to be repainted * @param left Left edge of the rectangle that should be repainted * @param top Top edge of the rec

 * @param bottom Bottom edge of the rectangle that should be repainted
 */
static void DrawOverlappedWindow(Window *w, int left, int top, int right, int bottom)
{
	Window::IteratorToFront it(w);
	++it;
	for (; !it.IsEnd(); ++it) {
		const Window *v = *it;
		if (MayBeShown(v) &&
				right > v->left &&
				bottom > v->top &&
				left < v->left + v->width &&
				top < v->top + v->height) {
			/* v and rectangle intersect with each other */
			int x;

			if (left < (x = v->left)) {
				DrawOverlappedWindow(w, left, top, x, bottom);
				DrawOverlappedWindow(w, x, top, right, bottom);
				return;
			}

			if (right > (x = v->left + v->width)) {
				DrawOverlappedWindow(w, left, top, x, bottom);
				DrawOverlappedWindow(w, x, top, right, bottom);
				return;
			}

			if (top < (x = v->top)) {
				DrawOverlappedWindow(w, left, top, right, x);
				DrawOverlappedWindow(w, left, x, right, bottom);
				return;
			}

			if (bottom > (x = v->top + v->height)) {
				DrawOverlappedWindow(w, left, top, right, x);
				DrawOverlappedWindow(w, left, x, right, bottom);
				return;
			}

			return;
		}
	}

	/* Setup blitter, and dispatch a repaint event to window *wz */
	DrawPixelInfo *dp = _cur_dpi;
	dp->width = right - left;
	dp->height = bottom - top;
	dp->left = left - w->left;
	dp->top = top - w->top;
	dp->pitch = _screen.pitch;
	dp->dst_ptr = BlitterFactory::GetCurrentBlitter()->MoveTo(_screen.dst_ptr, left, top);
	dp->zoom = ZoomLevel::Min;
	w->OnPaint();
}

/**
 * From a rectangle that needs redrawing, find the windows that intersect with the rectangle.