vulkan: fallback code for node-as-texture doesn't handle scaling right
Submitted by Matthias Clasen @matthiasc
Link to original bug (#788348)
Description
We ignore the current mvp, and always create a cairo surface with the dimensions of the node bounds. When there are scales involved, this leads to blurry/blocky rendering.
Instead, what should happen here is that we transform the mode bounds to screen coordinates to determine how many pixels we ideally need, and use that to size the surface.