36
$\begingroup$

What are some techniques for procedurally generating wear (chips, cracks, dents, etc.) on a mesh object?

For example, what are some ways I could do something like this:

enter image description here

but with more dents and detail? (and without having to manually duplicate objects everywhere)


The image above was created by duplicating some smooth shaded spheres with displace modifiers and intersecting with a boolean modifier.

$\endgroup$
  • $\begingroup$ Would a displacement map work? $\endgroup$ – Gunslinger Oct 15 '13 at 10:22
  • $\begingroup$ @Gunslinger If you can get it to take small to large chunks out of the object (maybe more on sharp edges?) I guess it would ;) $\endgroup$ – gandalf3 Oct 15 '13 at 18:43
  • $\begingroup$ I'd love to see you answering this yourself. I was thinking about generating an image based on this blender.stackexchange.com/questions/3370/…. Then create vertex weight from it (use for distributing particles). Or generating a texture map directly. I never got around to it (my real computer have gone missing temporarily. $\endgroup$ – Gunslinger Oct 17 '13 at 18:43
  • $\begingroup$ This guy shows how to model imperfection using dynamic paint. youtube.com/… $\endgroup$ – MarcClintDion Oct 19 '13 at 21:24
  • $\begingroup$ @Gunslinger I tried using a vertex group generated from a baked vertex color to distribute particles, but it didn't seem to be working. I then tried making the particles real and doing a Boolean intersection with the object, however that gave an error. I'll play around with using vertex colors mixed with procedurals and see if I can get any nice results $\endgroup$ – gandalf3 Oct 21 '13 at 0:56
33
$\begingroup$

A completely different way of simulating wear on an object, with the benefit of using only Modifiers, is Decimate in conjunction with Subsurf. The attached screenshot shows the default cube simply run through Remesh, Decimate->Collapse, Decimate->Un-Subdivide, then Subsurf. There is a lot of flexibility in this approach; changing almost any of the parameters in any of the modifiers subtly alters the distortions on the cube.

Simulating Wear Using Decimate

$\endgroup$
13
$\begingroup$

Using the Displacement feature in Nodes with an appropriate Texture:

  • If you don't care about actually displacing the mesh, this Nodes setup is certainly one simple way to create something like what you've displayed:Bump Displacement

  • If you need to displace the mesh, change the Object Data tab's Displacement setting to True. Just know that you will need a tremendous mesh resolution and/or Subdivision to get the equivalent sorts of bumps:True Displacement

$\endgroup$
7
$\begingroup$

If you set this object to be a Dynamic Paint Canvas, then you can use particles or other objects to damage this Canvas object by using an animation. Under the Dynamic Paint Canvas options, set the Surface Type to displace. This drop-down menu is found under Dynamic Paint Advanced.

Next add plane and rotate it to face the object that is to be damaged. Add a particle system to this plane and increase the value in the Normal field for Emitter Geometry which is under the Velocity header. This will cause the particles to shoot away from the plane instead of dribbling off.

Next, set this particle emitting plane to also be a Dynamic Paint Brush. Under the header for Dynamic Paint Source you should see a drop-down menu which is labeled Paint Source, change this to Particle System and below this you must also choose whatever name you gave to the particle system.

Now when you run the animation (alt-A), the particles should displace the mesh surface of the object that you want to show wear, so long as it's subdivided enough.

At this point, the particles will likely cause deformations to both sides of the affected mesh, to correct this you can set the object which is to be deformed to be a Collision object as well. Now the particles should bounce off of the object instead of passing through and influencing both sidessimple example.

$\endgroup$

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.