If - transparent is specified, then this option means that the colors will be mixed using an additive color model, as if the qixes were projected light. This is the default. If - transparent is specified, then this option means that the colors will be mixed using a subtractive color model, as if the qixes were translucent filters. Three will yield triangles, and so on. Whether there should be downward attraction.
Gravity is off by default.
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