Confusion over GPUParticles3D > Local Coords

[acarx]

Godot Version

v4.6.stable

Question

Based on its description, setting local_coords to false should ignore node transform (rotation/position). But in my experience node position and rotation affect particles regardless of what this property is set to.

After some investigation, I’ve narrowed down the problem to particle shader EMISSION_TRANSFORM. Removing this from transforms in shader code will make local_coords property work as described.

My question is, is it ParticlesProcessMaterial that’s bugged or am I doing something wrong?

[normalized]

@acarx

Based on its description, setting local_coords to false should ignore node transform (rotation/position)

It doesn’t ignore node transform, it just doesn’t parent the particle to the node after it’s been created. The particle emitter will still emit relative to the node.

[acarx]

If local_coords is true, will EMISSION_TRANSFORM in particle shader be an identity matrix then?

[normalized]

@acarx

If local_coords is true, will EMISSION_TRANSFORM in particle shader be an identity matrix then?

Likely.