XOR
{@usesMathJax} Discards the source and destination pixels where source pixels cover destination pixels. Draws remaining source pixels.
\(\alpha_{out} = (1 - \alpha_{dst}) * \alpha_{src} + (1 - \alpha_{src}) * \alpha_{dst}\)
\(C_{out} = (1 - \alpha_{dst}) * C_{src} + (1 - \alpha_{src}) * C_{dst}\)