Alpha to coverage

Alpha to coverage[1][2][3] is a multisampling computer graphics technique, that replaces alpha blending with a coverage mask.

This achieves order-independent transparency for when anti-aliasing or semi-transparent textures are used.

This particular technique is useful for situations where dense foliage or grass must be rendered in a video game.

Alpha-to-coverage converts the alpha component output from the pixel shader to a coverage mask.

When the multisampling is applied each output fragment gets a transparency of 0 or 1 depending on alpha coverage and the multisampling result.