MASKED
Masked blending mode, pixels are either fully opaque or fully transparent, based on a threshold.
Pixels whose alpha is less than opacityThreshold are fully discarded (clipped); pixels with alpha greater than or equal to the threshold are treated as fully opaque. There is no semi-transparent transition. When opacityThreshold = 0 (the default), every pixel passes the alpha test, so the visual result is identical to OPAQUE.