Otherwise the only difference between it and pasteSpriteToBackDrop
is the different color used for blending.
burnString is supposed to transform brightness into alpha. This is
pre-rendered already at load time in burnSurface, so use that.
While at that, remove useLightTexture TODOs from above-mentioned
functions. The only thing the original interpreter does with
useLightTexture in those places is to make sure it's disabled.