Difference between revisions of "Live 2022.08.23"

Revision as of 12:09, 9 September 2022

Shading techniques for Solaris, USD and MaterialX

Scene File

Get the Houdini scene here: data_disk_sim_007.hiplc

Summary

Building a shader from scratch in Solaris with MaterialX. The color values are retrieved from the geometry "Cd" attribute and the displacement pattern is generated using MaterialX math nodes to remap the surface position to a waffle grid-like bumpy pattern.

Below is the MaterialX shading network.

Video On Demand

00:00 Solaris LOP Stage introduction
02:50 LOP node concepts
09:10 Making a MaterialX shader
14:30 Using geometry attributes in MaterialX
15:30 Using other geometry properties to generate patterns
24:10 Enabling ACES through the SideFX Labs menu
34:40 Modeling a blobby shape
45:10 Adjusting lights and materials for the blobby shape
1:00:00 Looking at the structure of USD files
1:03:00 Adding studio backdrop geometry
1:16:00 Adjusting camera composition and render settings

Additional Scene Files

data_disk_sim_001.hiplc

data_disk_sim_002.hiplc

data_disk_sim_003.hiplc

@@ Line 8: / Line 8: @@
 == Summary ==
-Simple setup where a particle simulation is driven by pyro velocity field.  The geometry in the particle simulation is continuously resampled using a sop solver to maintain evenly spaced line segments and prevent some spiking artifacts.
+Building a shader from scratch in Solaris with MaterialX.  The color values are retrieved from the geometry "Cd" attribute and the displacement pattern is generated using MaterialX math nodes to remap the surface position to a waffle grid-like bumpy pattern.
-I use some simple VEX code to only allow velocities in the vel field in areas above a certain threshold.  This helps keep some parts of the line structure rigid and intact while other areas above the threshold are free to move.
+Below is the MaterialX shading network.
-<syntaxhighlight lang='C'>
-v@vel *= length(@vel)>.005;
-</syntaxhighlight>
-After the simulation, the curves get their normal by sampling the velocity field from the pyro sim.  This gives you a consistent (non-flickering) orientation of the curves when you render them.
 [[File:Screenshot_at_2022-09-09_13-00-32.png | 900px]]