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Increasing/decreasing number of particles dynamically by Key Up&Down.
Five simultaneous particle systems.
Easing curves to control particle:
1)Top-Left: Linear curve for decreasing the size of particles.
2)Top-Right: Linear curve for increasing the size of particles.
3)Bottom-Left: Linear curve for decreasing the velocity amplitude.
4)Bottom-Right: Quadratic easing in/out curve for changing the size and the velocity amplitude of particles.
5)Center: Cubic easing in/out curve for changing the rotation of particles.