Bump mapping - does a 128 grey colour produce the same as if the bump were off?

[DPS]

As per the title. I did a few quick tests and there doesn't seem to be a lot of difference in render time between my test scene with no bump maps, and bump map enabled but with 128 flat vray colour. Just wondered how it works?

Thinking of using a multisubtex to switch bump on/off for certain objects.

[vlado]

It will work fine... There is some speed difference, but it will be very minor.

Best regards,
Vlado

[DPS]

Cool, thanks.

[Dariusz Makowski (Dadal)]

Ignore. Bad post.

[DPS]

Another question regarding bump maps and compositing them together...

I've always struggled to layer procedural bumps on top of each other - sometimes they work and sometimes I get results that I wouldn't expect. Some maps don't seem to work properly when making adjustment to bump colour despite the preview looking correct.

So my question is (and I'm sorry it's quite a broad one) - would it be possible for someone to highlight some of the maps that don't affect the bump channel? I'm not sure whether this is vray specific - I was using mr until recently.

And regarding vray colourtobump map - does this overcome any problems related to the above?

I've not had chance to test this properly yet.

[Dariusz Makowski (Dadal)]

Can you please submit a test example scene ?

Thanks, bye.

[maxedesa]

You can put vrayColor2Bump at the end of composite or procedural bumps, for example a mix with multiple bitmaps inputs.

Does anybody know why procedural maps such as noise don't viewport display correctly? Is there a solution? That has always been so frustrating.

[viscorbel]

Does anybody know why procedural maps such as noise don't viewport display correctly? Is there a solution? That has always been so frustrating.

A couple of things you can do - first is to go to material editor options and set the "Render Sample Size" to 25 instead of 300. This should fix the size difference issues between mat editor, viewport and render.
The mapping will still be incorrect, but at least the size will be closer.

The second thing is TexMapPreview script from SoulburnScripts collection (free). Gives a very fast render of the object showing only the selected map (if you have a noise map selected in mat editor, it will render just that noise as diffuse on the object) So far this has been the only way I've found to get a decent preview...