Hi guys and girls!
Recently I'm studing how to proper use microdisplacement in blender, and I'm getting realy nice results.
But for some reason the final render got some weard blocks, like minecraft.
I'm using 8 bit displacement texture, so I know this can be the cause (maybe).
But how to fix that? Someone have any idea?
Or the only way to fix it is using a 16bit texture in the displacement?
Looks great. I haven't done much microdisplacement, but it definitely looks like the 8bit textures could be the problem. Have you tried the 16bit displacement maps yet? I know I have trouble with using 8bit maps for puddle maps. They just don't have enough information to make an even transition when I crunch the values.
Yes, it's like Philip said and you already suspected.
This is exactly what you get when using 8 bit textures for displacement.
That's why it's recommended to always use 16 bit Displacement textures, to avoid this 'banding' effect.
Maybe a little explanation is necessary...
With an 8 bit grayscale picture you 'only' have 256 values from black to white. This looks smooth enough as an image, but when you use that as height information, you will see the 'steps'.
With 16 bit, you'll have 65536 different values and although there is still stepping in the heights, you won't see it any more.
Like when an image is pixelated, you increase the resolution so that it looks smooth.