(Blender 2.62) I’m using an Emitter particle system, with No Physics, to create and position vegetation. (It’s set to render particles as instances of a plant mesh object.) The Jittered distribution with Even Distribution turned off is working well for this – plants aren’t getting placed close enough to each other to intersect each other, which is good.
The problem I’m having is with the “Randomize rotation phase” setting. I want my plants to be randomly rotated around the up axis so they don’t all look the same. As I increase the Random setting for the rotation phase to its maximum value of 1, the resulting random rotations I’m getting only vary between 0 and 180 degrees, rather than the full 0 to 360 degree range.
This is quite visible in the rendered result because, for example, the largest leaf on my plant instances always points in a direction within 90 degrees of north for every plant, and never in a direction within 90 degrees of south.
Is this a bug? Or is there a better way to do what I’m trying to do?
(Edit: The workaround I initially described here works, but there’s a better technique described later in the thread.
I think I found a different way to get what I want, but it’s a bit complicated, and I’d like to find something simpler. I selected Boids Physics for the particle system and let the particles (plants) rotate themselves around randomly for a while and then freeze. I used these settings:
- only allow the boids to move on Land
- set Max Land Speed = 0 so the particles don’t move away from their initial “Jittered” positions
- crank up the Max Land Angular Velocity
- set Banking = 0 so they don’t wobble
- set Height = 0 so they stay on the ground
- just have one Rule in the Boid Brain section: Average Speed, with its Wander set to 1 which causes the particles to rotate around randomly.
Then set the particle Lifetime to something like 600 frames or so and set the system to render Died particles. Then run the animation. At the end of the 600 frame “warmup” period, the particles will be pretty randomly oriented and they’ll die and stop moving but they won’t disappear.)