3d/2d Displacement issue. Wet asphalt/puddles

[DanSHP]

Hey

I'm throwing together a wet asphalt material but I've run into an issue...

I have a blend material.

Base: Asphalt
Coat1: General surface water
Coat2: Puddles - Stucco texture - mask

I decided to separate the surface water from the puddles for better control.

I have an asphalt displacement texture set up and working correctly, kind of.

In order for the displacement texture of the asphalt to work correctly in this instance, it should not also displace the puddle map!
So, in order to ensure this doesn't happen, I have an instanced version of the stucco map sat in a composite map with the displacement map. The stucco map is on top and set to subtract, so in essence telling the displacement map not to displace here.

Now, this all works splendidly using 3d displacement mapping mode, the problem with that though is, I cannot get a render to start at all (using this specific material) when using it in any of my scenes (they are usually large/complex and 5-6k )as max bombs/hangs. 2d displacement renders out but there is a difference, in that the displacement ignores my subtracted puddle/stucco map and displaces them too.

See images attached.
Set in a simple scene so no issues using 3d displacement

Whats the best way to get around this? Is this a bug?

[glorybound]

What if you subdivide your plane?

[DanSHP]

What if you subdivide your plane?

Yeah always a must with displacement, its fully subdivided.

[joconnell]

I always do debug things like this by putting the displacement map into a vray extratex to see what's happening - are you using a stacked map directly in the modifier slot or are you using the displace slot in each material?

[DanSHP]

I always do debug things like this by putting the displacement map into a vray extratex to see what's happening - are you using a stacked map directly in the modifier slot or are you using the displace slot in each material?

Yes it's a stacked displacement map.

[vaya_studio]

As far as I remember 2d displacement doesn't work with procedural maps with world or object mapping. It works if the texture's mapping is set to Explicit Map Chanel.

[DanSHP]

As far as I remember 2d displacement doesn't work with procedural maps with world or object mapping. It works if the texture's mapping is set to Explicit Map Chanel.

So, using 2d displacement, I've set my water stucco mask to explicit map Chanel no 2 and added another UVW map to the object on Chanel no 2.
Still not getting any joy.

Anyone from Chaos group want to chime in?

[DanSHP]

This also happens with bitmaps

[Vizioen]

It sounds overall quite complex for what you're trying to achieve imho. I couldn't tell heads from tails from the explanation (some visual aid would be helpfull). So I have no idea if what I'm about to say is actually the case, but if you have a composite map in displacement mod you have to use 3Ddisplacement afaik.

[fixeighted]

Found this post which may help. It seems simple enough to me but I can't test it right now.

https://forums.chaosgroup.com/forum/...lacement-decal

[DanSHP]

It sounds overall quite complex for what you're trying to achieve imho. I couldn't tell heads from tails from the explanation (some visual aid would be helpfull). So I have no idea if what I'm about to say is actually the case, but if you have a composite map in displacement mod you have to use 3Ddisplacement afaik.

It's pretty simple really.

I'm using displacement for an asphalt material. A blend material (water) is used to layer puddles on top with a procedural stucco mask. The puddles mask, is also instanced via composite map to subtract displacement from the asphalt displacement map, so that it doesn't apply displacement to areas where the puddles are. Right?

In 3d displacement, this works as intended (Image2). The problem is, its too intensive to use on my everyday scene.
In 2d displacement, it does not work as intended(image1). The subtracted stucco map is ignored, and displacement occurs where I have determined it should not.

If its as simple as 2d displacement not working with procedurals then that's all good.

[DanSHP]

Found this post which may help. It seems simple enough to me but I can't test it right now.

https://forums.chaosgroup.com/forum/...lacement-decal

Interesting. Thanks for this!

[Vizioen]

If its as simple as 2d displacement not working with procedurals then that's all good.

Indeed, that's always been the case afaik.