@ juliohm and sdanisch thanks for answering! May be my description was unclear. I dont need only voxel (cube) it was just minimal toy example. In reality volume will be with high number of voxels and different intensity of each voxel, CT like images. More real example:
But on more real volume is harder to explaing smoothing effect.
Anyway, just out of curisity as I understend clear MIP algorithm should not provide such smoothing effect or I’m wrong?