Particle System Issues and Suggestions

[Sergeant]

I've been playing around with the particle system in order to explore all aspects of the Love's capabilities. The particle system seems a little bit broken. setSpread() doesn't appear to do anything at all. If it's zero, then particles shoot out in a straight line. If it's greater than zero, then they shoot out in all directions. There's no in between anywhere. Even if I tinker with the particle demo included in the Love download it does the same thing. Is there something I'm missing?

Secondly, I was hoping to make a suggestion or two to the particle system for possible further enhancement since the documentation lists nothing similar.

Radius: This would determine the actual spawn point of the particles from the emitter's center. Ideally it would have two values so one could make an ellipsoid shape if they wanted (or even a straight line if you set one value to 0). This would result in a halo effect.

Radial Aperture: Determines the aperture around the radius particles would spawn, so you could have anything from a single point emitting to a quarter circle, half-circle, etc. of particles being emitted.

Orbit: Would be a value between 0 and 360 to rotate the particles emitted around the Radius, but not actually rotate the emitter itself. This way you could have, for example, a single particle point orbiting in an ellipse shape around something and potentially leave a trail.

Rotation: Rotates the entire emitter. Say you have a line of particles and you need it to be rotated in a certain way.

Radial Emission Direction: 0 for outward away from the emitter, 1 for traveling to the center of the emitter and disappearing.

Target: One could set up a movable target for particles to travel from one location to another, with some variation for different effects.

Stencil Blend Mode: This would be used for any image drawn on the screen, not just particles. There would be all sorts of uses for this effect, but my immediate idea is a portal effect. Essentially based on a sprite, image or particle alpha, a background texture of some sort would show through. One would be able to control everything about the stencil image so one might have an animation going on. One could have a global stencil background that would be the default for the stencil mode, and then there could be other backgrounds that images could be set to show instead of the global one.

[Robin]

setSpread() doesn't appear to do anything at all. If it's zero, then particles shoot out in a straight line. If it's greater than zero, then they shoot out in all directions. There's no in between anywhere. Even if I tinker with the particle demo included in the Love download it does the same thing. Is there something I'm missing?

I'm not an expert on particle systems, but have you tried values as 0.1 etc.? The value is in radians, not in degrees, if that's what you thought.

[Sergeant]

I'm not an expert on particle systems, but have you tried values as 0.1 etc.? The value is in radians, not in degrees, if that's what you thought.

Thank you. Given how late it was for me while messing around with that I don't know why I didn't think of using fractions. After tinkering about and using an extremely large number of particles (not recommended due to it being really bloody slow in computers without appropriate rendering speeds), I found that 6.3 is a full 360-degree distribution of particles. Going any higher than that number will just cause the distribution to overlap onto itself. Going lower in 0.1 (or less) increments will start concentrating the particles toward the set direction and leaving an appropriate gap.

[bartbes]

6.3, hmm.. that sounds awfully close to 2*pi...

[Robin]

6.3, hmm.. that sounds awfully close to 2*pi...

Well, duh.

[Sergeant]

6.3, hmm.. that sounds awfully close to 2*pi...

I didn't notice. Honestly some math just zooms right past me. And until I went digging I'd never even given a second thought to radians versus degrees or that 2Pi is 360 degrees. A few things my past schooling never taught me proper.