Vector Displacement??

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Is there Vector Displacement material somewhere. I have been trying to look for it but I can't find it anywhere. Simple Displace material seems to be only basic displace options. And if there is nothing. Is it possible. to build one. I'm not a programmer at all but I like to do something sometimes. It would nice to know if that's possible. Maybe give a direction where to go.

By the way. This program is amazing. I just spended 99 dollars for HD version. I really like this program so far.
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I've never tried to make a vector displace per say, but you can probably go inside the Basic Displace and change it to your tastes.

Go to shops, select your basic displace, hit enter to go inside, then select the displacement vop. You can add nodes in to the network to get the desired effect. If you also have a Shader View instead of looking at the viewport, you can see your changes in real time.
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The default Displacement shaders do a displace by normal. In VOPs this is the Displace Along Normal VOP. It can also be thought of as displace by vector.

To test this you can add point normals and warp them. Try in the Point SOP's Normal parameters:
$NX + fit01(rand($PT+1.001), -1,1)*0.5
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Thanks so much for that information. Here is a update. Good thing that you can see displace. And also good thing is that it's not only up and down but every direction. Bad thing is
that it dosen't look any how it should look like. Here is a picture

I'm not sure what P and nN means in displace node. I tried to understand that
P would be surface postition and nN would be the vector which direction I want to take my P position but it dosen't seem to work like that.

Attachments:
render.jpg (200.8 KB)

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Now it is working. If someone likes to try I can put it here on the forum. Now houdini works perfectly with this program.

http://www.3d-coat.com/texturing_sculpting.php?un=5814 [3d-coat.com]
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Hi,

Please post your setup so everyone can try and learn.

Thanks!

Cheers!
steven
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Here is a node tree. I added Normal map. My only consern is that did I add Normal maps normals right way or not. In this node I'm just adding the Displacement normal and Normal map texture normal together. If there is any better way do it If anybody can help.





I know that I'm doing something wrong because I get these black lines in my render.

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Do you have Displacement Bounds setup? Go to the little gear icon on your object node, choose Edit Rendering Parameters. Then under Mantra9.5->Shading, add Displacement bounds to your object by clicking on the right pointing arrow and click accept.
Set you Displacement Bounds to the same value you have in the “scale” parameter of your shader.
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Thanks silvina. That was one part of solution. I have been working with psyborgue who is a user of 3d-coat forum. And he was able to fix this material and now it working corretly. Everybody who wants this material can download it from:

http://www.3d-coat.com/forum/index.php?showtopic=2383&st=20&start=20 [3d-coat.com]
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Hey guys

Has anyone noticed that the shader setup doesnt do negative displacement correctly, it always displaces in a positive direction? Im trying to solve this issue just now but i cant see where its going wrong.

Related to this very useful shader, Im also working on a vector displacement baker from within houdini. Theres no tracing involved so its pretty quick and should be accurate to.

Once we have a fully working shader and I get my baking tool finished up, I think it be a great addition to add this to the houdini exchange.

Cheers
Nick
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As for negative displacements from a texture map that goes from 0-1 (all positive values) you will have to rework the texture map values before it goes in to the Displace Along Normal (which does exactly what the name states: pull surface along the surface normal direction).

See the existing displacement by texture material for one method. I believe there is a menu option for displacement direction.
There's at least one school like the old school!
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yes,

the simple displacement material that is on the material palette has options for displacing:

up
down
both
Stephen Tucker
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The problem isnt quite todo with remapping/fitting our image to between -1 and 1 etc.

For example
If I use just the blue channel to displace with the displacement direction is correct i.e it works positively and negatively , but as soon as we use the normal direction defined by the the rgb values in tangent space the displacement direction is always positive.

The results of the displacement look correct for the “positive” direction which is why the examples shown work, the only problem is the inverse direction of the down displacement creating more positive displacement.

This looks more like a normal direction issue rather then a simple texture remap that defines the amount of displacement.

Just to be sure I tested this with that same up down set up as in the “simple displacement material” and there's no change in the direction.

Any ideas why the tangent space normal direction would be doing this? Im still trying to figure this one out. If I get any further I will lets you know.

Cheers
Nick
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Heres an image of the problem to help clear up my last post.

Attachments:
vectorDisplacement.jpg (142.4 KB)

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I have been suggested by a colleague to try and negate the normal direction if the blue channel is a negative value. If this works as we expect I will post a new shader here. Still unsure why we would need todo this.

Cheers
Nick
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Hi Nick

Been trying to get my head around this one as well. If I'm succesful, I will post

regards

Erik
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Hey guys
Looks like the negate of the normals sorts the normal direction problem I will do a proper vector displacement test and make sure the displacements are correctly offset and theres nothing odd is happening due to this, but my up down texture test works so far.
Cheers
Nick
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Afew more tweaks and I will post the shader update, im currently trying to figure out the best approach when using exr maps that are black = 0 and maps that use 50% grey as 0.

Cant quite get the exact values i need from it, its close but not quite right. From what i read in the 3dcoat forum, the 50% grey = 0 image maps are normalised and will make it trickier to get the displacement amount. these need the usual offsets as well.

but the black = 0 maps aren't normalised so should just need scaled down …. but doesnt seem the case with my modo test displacement files. These exr files support negative values and dont need offset like the 50% grey image maps.

Almost there.
Nick
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Hi Nick

Any chance of posting your node tree so far?

regards

erik
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Sure no problem. I will clean up the file and post it on here at some point today.
Cheers
Nick
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