Jump to content

Creating impossibly sharp ridges


Recommended Posts

Hello. Another C4D-inspired post, from here.

 

To tackle this, a displacement shader can do an excellent job at render time, using standard geometry, that would otherwise require unreasonably high poly counts, if modeled.

 

The below image, rendered in Mantra, uses a curve (rather than a texture), to define the displacement area, and the shader can use a ramp to create the falloff.

 

Mantra might be slow, but the quality it produces is evident from the extremely clean displacement it generated. I'm not fully comfortable with Karma, but I believe I can reproduce a similar image with it.

 

If you inspect the attached scene, you'll see a bog-standard setup with the geometry. All the magic happens in the material shader, where you can query the distance between two objects (at render time), and then drive a displacement with that information.

 

 

ridges.png

Displacement Shader with XYZDist (Mantra).hiplc

Link to comment
13 minutes ago, Cerbera said:

Well that's all very clever and reassuringly smooth.... for those of us without Houdini, can we have a wireframe screenie ?

 

CBR

 

Not much to see in the wireframe. Just a standard sphere and a curve projected onto it.

 

image.thumb.png.7182777340939012b34ddd91ab5e32d3.png

Link to comment
1 hour ago, eikonoklastes said:

 

Not much to see in the wireframe. Just a standard sphere and a curve projected onto it.

 

image.thumb.png.7182777340939012b34ddd91ab5e32d3.png

Thanks for this cool file. I see the displacement stuff in materialbuilder1 so it seems like render time displacement is being processed. Is there any way to visualize the polygon count if all the material displacement were baked in? As if baked for export?  I think that's what people mean when they ask to see the wireframe.

Link to comment

Super stuff, EIKONOKLASTES. Looking fwd to jumping into this more soon. I did start on a VBD cloud in Houdini today. Baby steps.

 

This makes me think about what Octane does with Vectron, where it's not relying on polygons at all.

Link to comment
8 hours ago, MJV said:

Is there any way to visualize the polygon count if all the material displacement were baked in? As if baked for export?  I think that's what people mean when they ask to see the wireframe.

 

Rendering tech is possibly my weakest area, so I might be entirely wrong here, but I don't believe that you can convert a displacement shader into geometry. The renderer is working in camera space, and translating the displacement data into micropolygons and mapping them to screen pixels. It does not build a 3D object.

 

The only way to visualise it would be to actually model it, and it would be impractical to do that, because the poly counts on such a sharp ridge apex would need to be astronomically large to resolve cleanly.

 

Again, I might be talking far out my ass here, so any rendering gurus, please do chime in. 

Link to comment
  • Recently Browsing   0 members

    • No registered users viewing this page.
  • LATEST ACTIVITIES

    1. 7

      Draw primitives on surface of existing objects?

    2. 0

      Nodes Modifier result isn't updated anymore

    3. 220

      Scene Nodes | Capsules file pit

    4. 3

      Flipped clones in multi-segments curve

    5. 2

      How to create continuous UV texture for irregular wall like shapes ?

×
×
  • Create New...

Copyright Core 4D © 2023 Powered by Invision Community