Cycles Needs More Bumpmap Depth for Outdoor Enviroments

Serengeti (Rhino WIP)
#1

Cycles renderer, as implemented is coming along fine, and I feel that in most cases it can easily replace Legacy renderer, but one. I’ve found that bumpmapping is not large deep enough for outdoor environments. I feel that the ability to have a deep bumpmap is handy for doing more-realistic terrain.

Having such bumpmaps may also be used to keep cityscapes manageable while making them realistic. Entire building facades can receive simulate light effects with the addition of a simple bumpmap. I would guess that presently, in the current bumpmap is limited to 2"-4" or about 50mm-100mm, perhaps less.

I also did a test, in which I found that Legacy renderer could do a deep enough bumpmap to make nice water, but Cycles, currently can not. I feel that having this bumpmap capability may help keep people who make boats and ships in Rhino. In my test, I found that a simple texture can make a pleasing water effect, where a 34 million triangles barely equals it. It also took quite some means to create a manageable mesh, created from block’ed submeshes.

Thank you for reading this far.

#2

This is due to limited bump map strength ,logged a feature request for UI in v7 PBR material:

https://mcneel.myjetbrains.com/youtrack/issue/RH-57447

2 Likes
#3

Thank you, @nathanletwory.

In the past, I’ve have had issues with it being too strong, and had to lower the contrast on some material bumps as well.

Perhaps the perceived value, would be logarithmic? exponential? Or for extra credit perhaps even in units.

I understand that the bitmap is only 8-bit, and there is only 255 levels of depth, and so it would seem that it’s a little tricky to get right.

Would a stepped gradient calibration texture help?

#4

Or use a 32-bit image, with all data in floats you’ll get already much better control.

#5

Photoshop can use 16-bit grayscale images, but not everyone would be comfortable using them.

[Let’s see… In the same drawing, I have paint-streaks which are about .0625" or even .03125" * 255, would be only 7.968" , so 8-bits would be exhausted with a linear scale, if trying to do 12" of perceived bump.]

[In Quake 1,2, the walls were made about 16 inches/units to avoid z-fighting/HOM, from shallow z-buffer sorting depth available on the early GPUs. It wasn’t an esthetic thing : ) ]

#6

TIFF supports 32-bit data. EXR as well.