Particles don't care about frame time

[einarf]

On some systems particles are :

• Not moving smoothly
• Have a longer or shorter lifespan based on framerate
• Fades faster or slower based on framerate

Looking at this briefly it's clearly realted to update() methods in sprite and spritelist.

Frametime was probable hardcoded because update don't have frametime parameter:

arcade/arcade/particle.py

Lines 101 to 104 in a0213ac

	def update(self):
	"""Advance the Particle's simulation"""
	super().update()
	self.lifetime_elapsed += 1 / 60

We do have an on_update method now that takes a frame time. The whole update vs on_update siutation should probably be resolved in the next major version of arcade. For now I think moving the logic to on_update and calling that from update with hardcoded delta time is a possible fix. The Emitter should be changed to call on_update and we need to somehow find a delta time to pass in without breaking anything.

[pushfoo]

This is still a valid ticket as of 2023.

[einarf]

Yes. It's a general frame time issue in arcade. I put it on 3.0 milestone for a reason. We need to solve this before release I think. It's very imporant.

Arcade currently works with ticks assuming 60fps. This is how sprite and sprite velocity also works now. We should make a thread about this on discord and figure something out.

[DragonMoffon]

could be fixed with issue #1795.

[einarf]

Fixed in #2288