Hello everyone,

I have a strange thing going on while rendering grass using the Fur tool: the strands always rendering black, and I don't know how to solve this! I took some screenshots when the problem occured:

• In the beginning of the rendering process, the grass looks fine (image 'fur 1')
• Once it gets into the progressive sampling, the grass turns black (image 'fur 2')
• It stays like this when the render is finished... (image 'fur 3').

I tried changing the material (Vray material, Sketchup material, just a plain color, ...). Only when it has no material whatsoever, it renders white (image 'fur 4'), in all other cases: black.

I noticed when I create a fur object in a different file and paste it into my project, this object renders fine, but not always (or only for a while).
I have had this problem several times over the past weeks with various projects, so it is not linked to this specific Sketchup file.

Anyone has an idea how to solve this??

greetings,
Ana

Hello everyone!

concerning UVW mapping of materials in Vray for Sketchup, I have two questions:

• while customizing materials, I came across the option to choose a UV channel/set in the 'texture placement' menu. By default, this is set to 1 but you can change to any number up to 99.
  My question is, where can you define these different channels?
  It would be extremely handy to have different channels with different sizes, in order avoid tiling on large surfaces etc...

• I read that in 3ds max there is the possibility to somehow randomize your UVW mapping, so that copies of the same object (eg wooden planks of a book shelve...) do not look exactly the same. Is there a similar option in Sketchup?
  Right now, my solution is to manually manipulate the texture of every object by moving and rotating it, but as you can image this quite time consuming when it comes to making 50 fence poles look good...

Hopefully, somebody can shed some light on this!
A very grateful thank you!

Ana

@andybot said:

Unfortunately, you're limited to the one channel that SU uses, so additional maps can only be mapped relative that that channel (you can use the UVW transforms like scale and rotation.) There's no way to add additional mapping per material.

So, if I get this right: in the 'texture placement' menu, you can choose a UV channel/set (by default set to 1), but there is no way to assign and use these different channels?
Does this make sense to anyone else?

Hi Flordelis,

I was facing the same problem: trying to mask out the background through glass with complicated shapes (trees...) in the foreground.
In my search I came up with this solution, which is not perfect but did the trick for me:

• glass material: in the refraction menu, set 'affect channels' to 'all channels', set refraction color slider to the right (completely white)
• add 'background' to your render elements, this can be then be used in postproduction to mask out your background, also through glass

As you can see, it is not the perfect solution since it only seems to work when the refraction color is set to white, but maybe it can be of any help!

Good luck!

You are right, that was the problem...

thank a lot for your quick and useful reply!!

Hi everyone!

i am a relatively new 'Vray for Sketchup' user.
Since yesterday I encountered a problem that didn't occur before:
when I render my model, all render elements come out fine EXCEPT for the MaterialID which turns out completely black and the ObjectID which turns out completely white. Strange!
I tried rendering a model already I rendered before (with all passes turning out just fine back then) with the same result: completely black MaterialID and white ObjectID.

Anyone recognizes this problem or/and knows how to solve this?
My gratitude will be yours forever! ​

I am using Vray for Sketchup 3.40.04 and Sketchup Pro 2017 (version 17.2.2555) on a windows laptop.

Thanks!
Ana