– The greater the “Random Size” value, the greater the variation of the radius of the particles.
– Random Size = 0 means no variation, all particles have the same radius.
– Random Size = 1 means maximum of variation: radius assigned to the particles can vary from 0 to the value you set in Size.
– In this example Random Size = 1
– On the right you can see how particles with differen radius (randomly assigned) interact with another particle system.