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toonafish
10-06-2006, 06:50 PM
why do I get such a terrible texture quality in Mental Ray. I tried looking everywhere for some filter or anything else that's active but I couldn't find any setting that improves the quality.

Here's a link to a sceengrab, on the left you see the original quality, on the right you see what I get in the render region.
http://www.toonafish.nl/clients/texturequality.jpg

any tips ?

thanks

toonafish
10-06-2006, 09:17 PM
Did a little check, this is what I get in Modo with the same texture, object and UV map. There seems to be some filter screwing up the texture in Mental Ray.

Anyone ??

http://www.toonafish.nl/clients/texturemodo.jpg

ndog
10-07-2006, 05:06 AM
Can you apply the same texture to a sphere in the same scene and not have it mess up?

Atyss
10-07-2006, 05:08 AM
I think lighting your scene would be a good starting point. Also, using a blinn or phong instead of lambert would definitely help.


Cheers
Bernard

elfdestruct
10-07-2006, 05:59 AM
That sort of blockiness is usually what you see at the render region default settings, just try cranking the slider along the border of the region.

To get more precise, go directly into Render > Region > Options and tinker with the AA levels, drop the Threshold & experiment w/ the Filtering to get a sharper look, similar to your initial tex & without the blocking.

There's a plethora of official documentation, I suggest you go over it before dropping such descriptors as "terrible." Also, I'd rather not go into more minutiae right now, it's Friday night. :)

toonafish
10-07-2006, 08:57 AM
elfdestruct: thanks, but I tried upping the aliasing settings, tweaking image filters and tried to find something in the docs that might help. That's not the problem, it's really the texture that's rendered blocky. What's wrong with teh word "terrible" ?

Atyss: It's a phong shader, but why do you think changing the shader and lighting the scene will remove the blockyness of my texture ?

Per-Anders
10-07-2006, 09:07 AM
It looks very like a strange subpixel sampling problem (almost like the subpixel algorithm has the pixel blending algorithm back to front) though those blocks are larger than a pixel. If you're using a MIP map or any other style of texture alias smoothing effect maybe try without or drastically reduce the sample distances (delta) used.

toonafish
10-07-2006, 09:15 AM
I just remember that I used the copy/paste UV in the texture editor, I think that might have something to do with that. I just checked the UV's and they are screwed up.

This is what I did. I imported an lwo with Pointoven. It failed to import the UV's, so I loaded an OBJ of the same geometry and used the copy/paste UV's to copy the UV's from one object to another. At first sight the UV's looked okay and in Open GL the texture did too, so I did not bother to check.

Could it be copy/paste UV's is buggy ?

Saturn
10-07-2006, 10:04 AM
Do you use eliptical filtering ? Did you uncheck the bilinear interpolation ?

toonafish
10-07-2006, 12:11 PM
I used Gator to transfer the UVs now, and the texture looks much better. I have to fix some seams manualy Gator wasn't able to transfer now, but at least I can move on.

Looks like copy/paste UV's is not working.

Thanks for the help peeps.

Atyss
10-07-2006, 02:39 PM
Sorry I missed the initial point completely (slapping myself on head).

It seems you are using JPG. Have you tried PIC, TGA, or uncompressed TIF?


Cheers
Bernard

toonafish
10-07-2006, 03:01 PM
Sorry I missed the initial point completely (slapping myself on head).

It seems you are using JPG. Have you tried PIC, TGA, or uncompressed TIF?


Cheers
Bernard

I initialy used JPG, but then converted the image to TGA. That's why XSI named the clip JPG, but it's actualy a TGA file. Didn't make a difference though, it was a UVmap problem ( see posting obove )

Thanks for the help though.

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