File Filtering?

#21

The EXRs output by imf_copy are viewable in the file node and the viewport (I can’t run 2.0 on this machine but don’t use that anyway even when I can)

But keep in mind this is most beneficial for large textures so loading it in the viewport might become expensive.

As for extreme close-ups of a texture showing artifacts, that’s to be expected. Textures at the lowest pyramid level are their base (original) resolution, which may be ineffective when close. That’s the same as blowing up an image and seeing pixels. Filtering cannot create data where there isn’t any.

However, mipmapped/tiled textures can be very large in size/resolution and handled efficiently when rendered so you can use a higher resolution image to begin with that will hold up to a close-up.

#22

I’m aware they are, but I don’t think they should be. I still should be able to use filtering, exactly for close up.
You need to load the plugin, OpenEXR, then you can see them in the render view.

Als

#23

Awesome work once again :beer:
Please keep doing these articles when you can, they really are fundamentally important !

#24

I still should be able to use filtering, exactly for close up.

Filtering for a close-up would actually blur or destroy information that should be visible. I would suggest using a high resolution texture instead or procedural that has no fixed limit.

#25

With Maya Software, filter was used to do blurring of an image.

With Mental Ray, that way will no longer work:

http://download.autodesk.com/global/docs/maya2013/en_us/index.html?url=files/GUID-F27DAC8B-B359-4A1B-BF30-53915272634C.htm,topicNumber=d30e535558

http://download.autodesk.com/global/docs/maya2013/en_us/index.html?url=files/mrfMS_High_Quality_elliptical.htm,topicNumber=d30e661912

What we need is an actual compositing node to do blurring inside Hypershade. :wip:

#26

I’m a little confused by this post, the docs you post say that filtering does in fact work with mental ray but that the pre-filter option is not supported. (Filtering happens but the pre-filter has no effect on increasing or decreasing blur)

Also, elliptical filtering (as discussed in the Elemental Ray blog) is your best option and it is a mental ray feature.

Take a look again here for the method we (and nVidia) recommends: http://elementalray.wordpress.com/2012/04/17/texture-publishing-to-mental-ray/

Also, ray differentials (a separate string option) in mental ray can also improve the filtering seen in a secondary raytraced effect.

#27

@enzym: I also must disagree with you. File texture filtering is not intended to “blur” an image file texture, but to clarify and clean it up. To reduce or eliminate moire patterns, and to above all reduce aliasing when possible in the texture itself, as opposed to edge antialiasing in the rendering engine.

The blurring you’re used to from using quadratic filtering on low-res textures is a byproduct of improper filtering.

#28

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