Varying Properties Over Time
Many of the numeric properties of particles or even the whole system can be varied over time. Unity provides several different methods of specifying how the variation will happen:-
• Constant: The property’s value is fixed throughout its lifetime.
• Curve: The value is specified by a curve/graph.
• Random between two constants: Two constant values define the upper and lower bounds for the value; the actual value varies randomly over time between those bounds.
• Random between two curves: Two curves define the upper and lower bounds of the the value at a given point in its lifetime; the current value varies randomly between those bounds.
For color properties, such as Color over lifetime, there are two separate options:
• Gradient: The color value is taken from a gradient.
• Random between two gradients: Two gradients define upper and lower “bounds” on the color value at a given time; the value used is a randomly weighted average of the two bound colors.