Comment I'm betting it isn't gamma-aware (Score 1) 77
50% grey is a pixel value near 192, not one near 128. A pixel walue near 128 is much darker.
As far as I know, the engine doesn't handle this. It may even have some sort of hack to crudely compensate for the error, such as rendering things a bit more or less bold. Any such hack is unlikely to work with both white-on-black and black-on-white.
I think the problem is even implicit in the API. You can't just render to bitmap, cache the bitmaps, then generate pixels with any color.
Green on magenta tends to show the problem well. The edges shouldn't be dark. Giving equal brightness to each color, converting to greyscale should make the text fully dissapear. (identical pixel values)