Hi,
Recently I have played with “scattered guides”, it's new fur feature in Houdini11. And I have faced strange results of calculation “guideorigin” in cvex shader. Bug does not appear every time and is random for each computer. I have created simple scene for checking. I have tried to calculate «guideorigin» in different ways.
In the first way, I have used sop method and result is always correct.
In the second way, I have used cvex shader and result is sometimes wrong. You can open scene and you will see some colored tubes (guides) and around of them a lot of colored fur – it's visualization of «guideorigin». If you change «density» parameter in fur_shader operator a little bit, between 0 and 0.5 then you will see a lot of white fur (if you look in «Details View” for prim., you will see a lot of zeroes for guidorigin attr.). Values for «density» is different for each computer and you should find it (for me it's 0.4 and less)
You can save scene and open again, result of calculations doesn’t change. To see right result – you should set 0 in global_switch operator. Below I have attached some images for illustration purposes. The code of cvex shader is very simple – just read “rest” or “hairroot”.
What's happen with calculations?
