Interface ParticleEmitterOptions

alpha at birth and at death, or a curve of the particle's age - see scale

emission direction in radians; the default sprays in every direction

A per-frame wobble on the scale, between 0 and 1: each frame every particle's scale is multiplied by a seeded draw in [1 - flicker, 1], so a flame's size jumps instead of sliding. 1 lets it drop to nothing, which with a scale curve of (t) => 1 - t is a torch spark. Dropped under reduced motion, like the travel and the spin.

A texture sequence each particle walks across its own life - the four frames of a flame, the puff of smoke - taken in preference to texture, whose place it takes. Chosen by the particle's age rather than the emitter's, so a burst does not flick through the frames in lockstep.

constant acceleration, world units per second squared - the default falls nowhere

seconds a particle lives

how many particles can live at once. The pool is allocated once at this size and never grows

particles emitted per second while start()ed; 0 makes the emitter burst-only

scale at birth and at death, interpolated across a particle's life, or a curve of it

where in local space particles are born; without one they all start at the origin

initial speed, world units per second

rotation change in radians per second

drawn per particle; omit for a pure simulation that renders nothing (tests, headless)

Multiplied into every particle sprite, either one colour for the whole emitter or a [from, to] pair each particle draws its own colour from, channel by channel - water with a depth to it rather than one flat tint. Ignored without a texture.