I essentially want to emit confetti particles. Each particle is the same shape, however, I want each particle to be a random colour from a selection of colors I specify.
Is there a way for each emitted particle to have a random color or do I need a separate emitter for each particle color?
You can use single emitter to achieve what you want:
EDIT:
Try changing duration of wait action to get different results.
You can play with color ramp too (in particle editor) to achieve the same effect:
Or you can use particleColorSequence and SKKeyframeSequence in order to change particle color over its lifetime. Hope this helps.