Hans Goudey
c007e84e9e
On NVidia GPUs, when the blue channel was between 0 and 0.1, the overlay's alpha would increase, making it invisible. With the `overlay_line_fb` frame buffer bound in `overlay_engine.cc` there are two outputs to write to: the color and the line output, which is used for making smooth antialiased lines. The overlay is in its current position in the order of overlays so that it draws on top of curve wire lines. Not writing to that second output is undefined behavior, so fix it by writing zeros. In the future, the overlay could be smoothed on curves using that second texture. Thanks to Clément for the explanation of the issue!