Better support for Bump and Opacity maps

[rita_sobral]

Hello guys,
I know these have been asked about previously but with no solid plans announced I would like to ask what are you plans for properly supporting Bump and Opacity in Vray material. Currently, they are very limited and force users to neglect them in their renders or try hacky workarounds which don't always get you what you want or is impossible to replicate another way.

Recap of their limitations and some use cases which current implementation causes issues. I understand the desire for optimization, mainly in opacity but I believe we should get the choice as a bare minimum so we can actually deliver the work we need without workarounds or simply not being able to include it in the final output.

Bump
Limited to purely bitmap textures
Does not support any type of procedural maps which are very common in assets created for Vray along with compositing different procedural textures which again is very common using mix, composite maps etc.
Currently does not support UVWRandomizer fully

Opacity
Only supports black and white values.
Limited to purely bitmap textures
Cannot create fog cards or cloud cards. Need to use refraction hack workaround which has its own issues.
Does not support any other type of map in the slot which would be used for creating effects such as holograms. Holograms cannot be created using the refraction workaround. You need to use the falloff map which when used in a refraction slot, black == no refraction (solid) whereas black in opacity means completely transparent.

Thanks

[npg]

These have significant performance implications (in some cases even if not used), so this is why we were avoiding them, ever since the first versions and first RTX cards. With Blackwell approaching, maybe we could reconsider, we now have much better speed than in 2018 (HW and SW improvements)...

[rita_sobral]

Yes I have no doubt that in the future this will change given advancements in GPU power, but I was curious to know what the plans were, if any, as these are issues I find myself up against on a semi-regular basis.

[vladimir.nedev]

Can you send us some sample scenes to test with ?

Greetings,
Vladimir Nedev

[hill_lam]

These have significant performance implications (in some cases even if not used), so this is why we were avoiding them, ever since the first versions and first RTX cards. With Blackwell approaching, maybe we could reconsider, we now have much better speed than in 2018 (HW and SW improvements)...

When I encounter some procedural maps that Vantage does not support, for example the Gradient Ramp in 3DsMax, I will right-click on the procedural map and select "Render Map..." in the Slate Editor, render it as a bitmap, save as, and then use this bitmap to replace the procedural map node.
When I need to adjust the parameters of the Gradient Ramp, I have to re-render the map, save it, and replace it.

Is it possible, for example, to connect a special node after the procedural map, let's call it "procedural2bitmap". VRay will ignore it, but Vantage will automatically help me render the procedural map, save it to the cache, and use this bitmap to replace the procedural node....All is done in the background.
I hope we can connect this node when we really want Vantage to render some procedural maps and don't mind sacrificing speed.

[vladimir.nedev]

When I encounter some procedural maps that Vantage does not support, for example the Gradient Ramp in 3DsMax, I will right-click on the procedural map and select "Render Map..." in the Slate Editor, render it as a bitmap, save as, and then use this bitmap to replace the procedural map node.
When I need to adjust the parameters of the Gradient Ramp, I have to re-render the map, save it, and replace it.

Is it possible, for example, to connect a special node after the procedural map, let's call it "procedural2bitmap". VRay will ignore it, but Vantage will automatically help me render the procedural map, save it to the cache, and use this bitmap to replace the procedural node....All is done in the background.
I hope we can connect this node when we really want Vantage to render some procedural maps and don't mind sacrificing speed.

We can do this internally, no need for a procedural2bitmap node.
However, this approach has a lot of limitations
- you have to use "explicit map channel" for the UV coordinate mode of the map (and you need to have proper UVs on the mesh)
- you can't use textures that depend on view direction (like falloff), object/world position, etc.
- if the procedural texture is infinite (like noise), baking it in a [1,1] uv square will show tiling outside of that [1,1] uv square.
- requires additional GPU memory compared to a real procedural texture (we will have to add a "bake resolution" option somewhere).

Greetings,
Vladimir Nedev

[vladimir.nedev]

Holograms cannot be created using the refraction workaround. You need to use the falloff map which when used in a refraction slot, black == no refraction (solid) whereas black in opacity means completely transparent.

I don't quite understand this part.
You can use the falloff map in a refraction slot, however Vantage won't evaluate the falloff map for shadow rays.
The same limitation will be present when we implement stochastic opacity.

The shadow ray intersections are implemented in special shaders that cannot evaluate procedural textures.
Dropping this limitation will probably make the shadow rays much much slower.

Greetings,
Vladimir Nedev