Texture fun

After reporting my texture problems since nearly a year I was hoping for some fixtures in the Rhino 7 version, but apparently it becomes worse with every new update.

What’s new is that textures are displayed wrong in ray tracing view but correct in rendered view, or vice versa like in the example below:

Rendered view (in the small picture to the left you see the original)

Ray traced view

This behavior is so inconsistent that I cannot think of any explanation.
Thanks for your help
Cyana

On what service release are you at the moment?

With @Jussi_Aaltonen we have been looking quite a lot at your problematic models, but I was under the impression we managed to fix at least most of them.

For the pipes that are marked wrong in the Raytraced view I believe I had given some instructions on how to do the texture mapping better in such a way that they are correct in both Rendered and Raytraced view.
Did you try that setup?

Hi Nathan,

thank you for your reply. My release is Version 7 SR8 (7.8.21196.5001, 2021-07-15)

For the pipes that are marked wrong in the Raytraced view I believe I had given some instructions on how to do the texture mapping better in such a way that they are correct in both Rendered and Raytraced view.

I’ve reported part of the problem in May here and uploaded a file on your request, however did not receive an answer since. I might have missed it somehow, but at least in that thread there was no reply. If you or Jussi have a solution/instruction how to get around this, I’d be most grateful to follow.

thanks a lot
Cyana

Hmm, I have the distinct memory typing some instructions regarding your texture mapping usage, but I can’t find the post anywhere. I must have not sent it at some point. I’ll re-type the findings I had made at the time and post them this time properly.

Thanks Nathan.

What’s new to the problem I reported in May is that since one of the last updates now also the uppermost pipe is displayed wrong in rendered view. No changes were made to this pipe meanwhile, actually it’s a generic material with a slightly weathered white texture used throughout the project for thousands of objects.

thanks
Cyana

Ok, seems that the dog ate the instructions.

I’ve updated the AMD driver to the recently issued version, this fixes the newly encountered material/texture problem.

However the issue reported here is still up.

thanks
Cyana

Ah yes. I was supposed to type them instructions. I don’t have a dog, so I have only myself to blame for not typing them in again and send them.

The thing that stood out most to me was your use of texture mapping. For instance with the tubes you use Cylindrical mapping, which in itself is a good thing. Except in some cases you have the cylindrical mapping placed such a way that essentially the cylinder and your tube are at a 90°.

Also, you’re using the Ray projection, which doesn’t really work in Raytraced/Rhino Render.

Orienting the texture mapping properly, more closely matching the geometry you’re mapping on, and uisng closest point projection should yield you results that work for both Rendered mode and Raytraced/Rhino Render.

In the shot below I made a copy of the original vertical pipe, moved that to the back, and redid the texture mapping on the one in the foreground. It has now a cylindrical mapping that is closer to what the geometry is, and closest point is used. You can see that the Rendered and Raytraced viewports now agree.

Apologies for dropping the ball on this.

Addendum: I forgot to say that since your textures are only simple lines you can do your pipes even with simple planar mapping. If you then want to optimize the texture you could make it just one pixel high or wide as well, since the pixels just repeat in that direction

And a version with just the simple planar mapping,ever so slightly faster (simpler math)

Hi Nathan,

thanks a lot for your extensive and helpful reply!

Except in some cases you have the cylindrical mapping placed such a way that essentially the cylinder and your tube are at a 90°

I think this is because I applied the texture to the whole, initially horizontal cylinder to get the correct proportions and then split it and rotated the vertical portion upward. I was not aware that this is a forbidden technique.

For the horizontal part, switching from Ray to Single Point projection does the trick. However I have to confess that I’m not sure how you fixed the vertical portion. Did you delete the original mapping and then assigned a cylindrical mapping from the scratch and rotated the UVW to 0,0,-90 ?

And a version with just the simple planar mapping,ever so slightly faster (simpler math)

Wow, thanks a lot! Did not know this would work.
Best greetings and thanks!
Cyana

Ah, I forgot one step. I indeed deleted the original mapping, created a new cylindrical mapping. But the easiest to control this was to have a duplicate of the material, and then rotate the texture.

  1. delete original mapping
  2. add new cylindrical mapping
  3. duplicate material
  4. assign duplicated material to pipe
  5. select duplicated material
  6. select texture in duplicated material
  7. set rotation in texture mapping section, I believe it was set to 270°

In the end I think using the planar mapping in your case is going to be easier for these pipes. And as said you could save a few bytes by making these simple textures just the one pixel high (or wide, I forget which way around the stripes go)

Hi Nathan,

again, thanks a lot for your helpful advice! I’ve now reduced the width of the textures to 1 pixel, and replaced the material. Is there an advantage of planar over cylindrical mapping? - the new texture works perfect with the original cylindrical mapping, too.

thanks
Cyana

In Raytraced the rendering is the tinies bit faster. There is not much difference. But use the one that fits your needs best :slight_smile:

:wink: Ok. Since I’m lazy, I leave it as is. However, there are still some pipes left, who need to be textured, where I will try the planar approach.

best greetings and thanks
Cyana