Create enum EmitterShape to allow for emitters other than circles #33
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| let rotation = Quat::from_rotation_z(angle); | ||
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| Transform::from_translation(rotation * vec3(0.0, distance, 0.0)) | ||
| .with_rotation(rotation) |
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I think this causes us to not correctly respect rotate_to_movement_direction if it is false. So I think we don't want to set transform rotation here (or for CircleSegment) and let the code in the spawn system do it after we return this transform.
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It should get accounted for in the particle_spawner system in Line 142 and the following, where I override the transform.rotation if rotate_to_movement_direction is false. My thinking behind doing it that way, was that we need some way of communicating the movement direction of the particle from the EmitterShape back to the system, because the system does not really have a way of determining it. So some information about direction has to be communicated back from .sample anyways.
So the rotation of that transform basically describes the direction of movement, and not necessarily the rotation of the particle.
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Ahhh, ok, I see it now. Perfect!
| let rotation = Quat::from_rotation_z(angle); | ||
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| Transform::from_translation(rotation * vec3(0.0, distance, 0.0)) | ||
| .with_rotation(rotation) |
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Ahhh, ok, I see it now. Perfect!
Co-authored-by: Abnormal Brain Studios <102993888+abnormalbrain@users.noreply.github.com>
I quickly threw this together for a project of mine, and thought I could as well ask if this is something that could be integrated into the upstream library.
I ran into a situation where I needed particles to be emitted from a line (think Clouds in the background e.g) and found no easy way to do this with this library, so I bundled the three
spawn_radius,emitter_shapeandemitter_angleproperties of theParticleSystemtogether into an enumEmitterShape::CircleSegment. Another variant of this enum isEmitterShape::Linewhich has similar fields that describe a line with a given length - possibly at an angle.This enum has an impl with the
samplefunction, which returns a random point on the shape of the emitter, which gets used by theparticle_spawnersystem to determine the position and orientation of a newly spawned particle.I also updated all the examples to account for this (breaking) change.