Distance Blend Shader?

[modjtaba]

Hi
Is there any feature like Distance Blend Shader which is similar to what vray and corona have?
any osl?

Thanks

[modjtaba]

I would be thankful for any help.
Default attribtransfer needs lots of vertexes to make accurate distance blend color data.
Its possibly like AO map but with a list that says which objects cast AO shadow.
Thanks

[juanjgon]

Sorry, I'm not aware of a shader like that in Octane, but perhaps another user could know a workaround, or perhaps even an OSL shader to make something like that. Perhaps you could ask this question in the general support forum.

Thanks,
-Juanjo

[frankmci]

I'm not a Houdini guy, so take this with a big pinch of salt. If I understand what you are looking to do, though, and assuming the basic mechanics of texturing are universal and apply to Houdini, then you can DIY.

It takes a little bit of setup, but it's pretty simple. Just build your own grayscale ramp appropriately projected in scene space to define the distance, then use that to drive the blend between your materials. Most of the time, a simple linear 2D ramp is enough. If you want to get fancy about it, you can use a 2D circular or (super fancy!) 3D spherical volumetric ramp attached to, and centered on your camera.

This example happens to be C4D, but it would work essentially the same in most 3D tools I've used over the last 25 years.

Ramp is grayscale and projected in world space.
Checker and clouds materials use object UV space (or local projections etc.)
Mix material uses the ramp to drive the blend between the two.
(I'm repeating the gradient and miss-aligning it with true distance here to make it more obvious.)

Back in the early days, we used to manually build and render our own, crude, 8 bit Z-Buffer passes for compositing this way.

I hope that makes sense.