DASD

Is it possible to use HLSL?
And more precisely, is possible to turn HLSL displacement code into geometry deformation in Houdini?

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My research so far:
GLSL is used for viewport rendering in Houdini and it is possible to write custom viewport shaders in GLSL. (https://www.sidefx.com/docs/houdini/shade/glsl.html)

The docs indicate, that GLSL can also be used for rendering. I suppose this would make it possible to bake the shader to geometry.
(https://www.sidefx.com/docs/houdini/shade/glsl.html)

There seems to be at least one HLSL to GLSL converter.

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But this looks like a really terrible idea for a pipeline. So is there something more direct?

Bump. Any ideas?

Gomo
I want to have ability to tweak LOD screenSizes or other parameters for all instances of given HDA class without using Houdini, just parameters in Unreal.

I think that is not currently possible. If you want a change across all instances of an HDA you have to do that in the HDA definition in Houdini.

However, in recent releases of Unreal you get a Python API, so I guess you might make a tool that will be able to select HDAs in your scene and change their parameters. But to my understanding this will be overkill and rather useless. I would suggest to figure such things out once and then lock them in in the HDA. Even in worst case scenario, the amount of times to tweak such things can probably be counted on one hand…

I am not sure whether it is part of your issue, but you can give every exposed parameter on your HDA a reasonable preset value that will be prefilled when you put down the HDA (in Unreal or anywhere).

You can also do things with additional parameters that are not exposed, so maybe all the instances of the HDA in Unreal would be able to keep their settings, but you have an offset in the Definition that you can tweak if necessary that changes the final value.

I do see potential for global controls, though. It's probably worth an RFE. Though there are much more pressing issues that should be fixed first (like the ability to set arbitrary Unreal attributes - which might help create workarounds for this issue.)