3D particles

particles3d is a 3D emitter: one quad on the node, drawn once per live particle in a single call.

• direction and gravity are world-space vectors, and size and size_end are world units. spread_degrees reaches 180, which scatters every way.
• billboard turns each particle to the camera. Off, they lie in the node's own plane, turned by rotation_degrees and spun by angular_speed_degrees.
• texture, material, light_layers, render_layers and the overlay keys apply as on a multimesh3d. cast_shadow is off by default.
• A color_end with a lower alpha fades the particles, because a translucent instance sends its node to the transparent pass.
• Live particles are renderer state seeded from the node, and a one-shot burst says finished on the fixed step, as the 2D emitter does.
• The 2D emitter beside it is particles2d. Godot's CPUParticles3D and GPUParticles3D import as particles3d.

[nodes.particles3d]
rate = 120.0
speed = 3.0
spread_degrees = 20.0
size = 0.15
gravity = [0.0, -4.0, 0.0]
color_end = [1.0, 1.0, 1.0, 0.0]