Computes statistics for every slice of a texture. The fragment shader passed as an argument is executed once per slice. The shader is expected to return computed statistics as a color. tex is bound to texture id 0.

Computes sliced-based mean values by utilizing DVR alpha shaders (dvr_alpha_*). The result is stored in a single-channel texture.

Converts a 2D texture with statistic values to an array of half-float precision.