Sunday, October 7, 2012

Particles aren't Particularly Pretty

This week, I explored the Particles tab of the Geometry context. I had very high expectations about particles; I know that particle effects can be very impressive, and I know that Houdini animators are in high demand precisely because of the software's great support for particles.

This short list of nodes has a great potential.
Or does it?

Well, I was quite disappointed.


The main problem with particles, in my opinion, is the tradeoff between control and randomness. When creating particles, the default is to create particles at each point in the geometry, in the order of the point numbers. This causes the particles to appear in rank and file, which doesn't look right. By randomizing the point numbers (using the Sort node), the particles look much better, but we lose a lot of control. The particles appear at different positions and move in different directions, which leads to some regions ending up cluttered, and others ending up empty. Not having any control over which regions is really annoying, because that has a big effect on the visual organization of the scene.

Left: Particles created in an orderly fashion are predictable, but look boring.
Right: Particles created randomly look much better, but are less predictable.


I hope that those problems are partly due to the fact that I am using particle operators in a Geometry context instead of a Particle context. The 6 geometry nodes I have explored today are a bit limited, but there are still 67 more particle-related nodes to explore in the Particle context! Allow me to explain.

Houdini has a few different kinds of networks, which are used for different purposes. The one I most want to learn is the Geometry context, which is used to manipulate the shape of the objects in the scene. I still have 189 nodes to explore there. Other contexts are used to define which materials they are painted with, how they move, and how they interact with each other. One of those, the Particle context, is entirely dedicated to particles. I expect that learning the 67 nodes from that context would allow me to create better-looking results than the mediocre trinkets I managed to create this week.

6 down, 189 to go!
I'll do better next time.

67 nodes doesn't look so big compared with the number of Geometry nodes I still have to learn, but for once, I'll try to finish what I have started!