I am learning to use particles and have set up a simple experiment. The disk is the emitter and a sphere with some projections is the particle.
I have managed to control the number of particles and to randomize the size, but I cannot randomize their orientation on their z axis. I have tried every control I can and none of them will allow me to do that.
Thanks for any clues.
PARTICLE Z ROTATION.blend (1.9 MB)You should be able to click where it says “Orientation Axis” and change it to either Global or Local Z axis. Then, the Randomize slider should work to add randomness. Take a look at the manual page here for more info: https://docs.blender.org/manual/en/latest/physics/particles/emitter/rotation.html#rotation
You are right - that is how it should work, but it doesn’t. I uploaded the file (above just below the photo). It would be interesting to know if it works for you if you would not mind running that experiment. Whatever control I try, the slider produces irrational rotations.
So, here are some things. Particle rotation worked like a charm for me. Now, I do see that you have the Particle Type chosen as Hair in your screenshot. I’m not sure what you ultimately want to do, but it doesn’t really look like you are making hair or grass with your project, so choosing Emitter is probably the better option. Next, be sure that you aren’t relying on the Angular Velocity setting under rotation to provide that random rotation you want when the particles are born. Go ahead and make those adjustments, and let me know if it starts working the way you want. See the image below for hints:
I think what you want is phase, don’t know why. Set the axis, then play with phase and randomize phase.
SOLUTION: Hair works for me, but emitter shows nothing, so I need to use hair. Global Z is the right setting. But then I need to select the particle (not the emitter) and tab into edit mode and select the entire object and rotate it until it appears upright on the emitter. Then, while still in edit mode, I need to move it until the origin point is at the bottom of the object. The result is that the object ends up lying on its side, but the particles are standing upright on the emitter - very strange, but developers move in mysterious ways and I never complain about Blender developers. Then to rotate it on the Z axis, I need to use the Random Phase slider as suggested by a59303.
Result, as you can see by this new photo is random size, random rotation - just what I wanted. Thank you for your suggestions.
Thanks to both Hunkadoodle and to a59303 for your help.
@John_Howard1, I’m glad you got it to work the way you want. Far be it from me to tell an artist how to make art, but you may be limiting yourself by using Hair instead of Emitter.
Learning a bit more about how particle systems work can help. Understanding how particle are born during emission, they have a lifetime, and that they die can make it easier to get them do what you want.
If you want all your particles visible at one time, there are a few things you could do. You could set your Frame Start and End values to 1. This will make all your particles emit during frame 1. (Relevant manual page: https://docs.blender.org/manual/en/latest/physics/particles/emitter/emission.html) That means all the particles die at the same time unless you had a lifetime randomness value set. If you needed your particles to have different lifetimes, this might not be the best option. You could still have your particles emitted over a longer span of frames while still being able to see your particles at frame 1 by telling Blender to render Unborn particles. This means that even before particles are born, they are visible in the viewport and in renders. If you don’t want your particles to disappear when they die, tell Blender that you want to render dead particles. (Relevant manual page for rendering Unborn and Dead particles: https://docs.blender.org/manual/en/latest/physics/particles/emitter/render.html#extra)
Hope this helps!
Hunkadoodle, Does it have an advantage to use Emitter rather than Hair? (when Emitter is not used for animation of course)
Great question, @moonboots! I guess it is one of those right tool for the job kind of answers. We’d need to have an idea of what @John_Howard1 intends to do other than 1) emit particles and 2) rotate them randomly. You asked about advantages “when Emitter is not used for animation of course.” I think you mean, that animating particles using the Emitter option is a clear advantage over Hair, is that right?
So, though rendering an animation with animated particles is an advantage of using Emitter, some people may want to render a still that includes particles that have been emitted using Blender’s unified physics system.
Additionally, Blender’s UI often removes options that are not available with the current context or selections. When you choose Emitter, you have some unique settings for particles that aren’t available when you select Hair - and vice versa.
Emitter:
Hair:
If you don’t need hair, you have better, more specific settings when you select Emitter. Those settings are simply hidden if you don’t select Emitter. Right tool for the job, I guess.
yes so I was wondering what were the tools you’d have access to when you choose Emitter instead of Hair, I thought you could do the same except animation, I’ll check that, thanks
