Getting "experimental" true displacement to work

Question

I have been trying to achieve a true mesh displacement on meshes for quite some time, without ever getting it to work.

If I understand it correctly, this experimental feature would allow me to easily displace the vertices of a mesh - or to create new mesh vertexes where needed - to get a displaced mesh in the result, based off an image, but without using a bump map (simpler, faster?).

This all sounds very exciting in theory, but I am having a really hard time finding examples or tutorials that are both recent and whose links function. So I think there is the need for a question here which will call upon detailed and recent answers to bridge that gap.

I'll start with a simple ico sphere:

Then, following Aldrik's answer here, I will change the Feature Set to the Experimental one:

I then add a pink granite image to the mesh:

Mark Seams, Unwrap, add image in the UV Editor:

and finally, in the Object Data panel, change the Displacement method from Bump to True as explained in Aldrik's answer:

no result yet:

if I click "Use Subdivision" this is what I get (so I won't click it right now):

Looking into the Node Editor, nothing seems to have changed with the Displacement of the mesh:

so I tried to replicate the node setup seen in the first image of this similar question (Linear isn't an option, Clip, Single and Repeat are):

... but the result is a white ICO Sphere, similar to Image 1.

So, can the "Experimental Feature Set" be used to create actual displacement, and modify a mesh?

This is what I'm trying to obtain - but with the image of the texture actually displaying on the mesh (image from here):

.blend file:

Answer 1

A UV Sphere is a better mesh to try this feature on (is made out of quads, and not triangles like the Ico Sphere and should subdivide better).

You need to plug the displacement texture to the displacement socket on the material output.

Render Feature set has to be in Experimental.

Displacement in the mesh section has to be set to True or Both.

To preview, you have to be in Rendered Mode in the 3D viewport. Other Shading modes will not reflect the displacement. Any changes made on the settings will not refresh in real time, you have to exit Rendered Mode (go to Solid or Wireframe Mode) and re-enter Rendered Mode to update (alternatively you can press the Tab key twice).

The more subdivisions you have on your mesh, the more detailed the displacement, but it will also have an impact on the performance of your computer.

Remember that this is still an "experimental" feature, so expect some unexpected results...

click on the image to enlarge

In my opinion, given that this feature is largely experimental, I'd still use a displace modifier. Is more predictable, responsive and easier to control. The results can be previewed in real time in solid and texture mode as well. Also, setting some subsurf modifiers in the right order can make things a lot nicer looking, and with a lot more control on the number of subdivisions. You can always apply the modifiers to make the displacement permanent, which you couldn't do using the displacement node.

Here's the same displacement, but with a displace modifier instead:

click on the image to enlarge

UPDATE: The option was under the Mesh properties at Blender version 2.76 but in more recent versions it has been moved to Material Properties > Settings > Displacement.

Answer 2

Time for update ... True Displacement (called also micro-displacement) ... you make it work in Blender in three steps ...

1. Render Engine

... is still available for Cycles render engine and still under Experimental Feature Set ... Dicing Rate specify details in pixels.

2. Modifier

Add Subdivision Surface modifier and enable Adaptive Subdivision this feature is available (appears) only for modifier stacked as last (if there is more modifiers).

3. Material

Under Material Properties > Settings > Surface switch from Bump to Displacement ...

... and under Shader Editor > Add > Vector > Displacement node ... for input socket use your height map or procedural texture ... output socket plug into Material Output > Displacement socket.