I understand the problem. Here's a question: what would be the impact of drawing "screen" nine times the current size, and showing only the center part, so that when you dragged slowly, the black would not immediately appear? Or perhaps drawing the surrounding parts from a lower resolution upscaled? That way, slight movements of the screen wouldn't necessitate a redraw. The black isn't fun, especially when we're just making slight adjustments; if it's necessary, we'll understand.