t property
The keyframe for this GradientPacket for retrieving the properties
of these respective a & b Gradients using an appropriate lerp()
method.
A value of t == 0 means this packet will return the properties of
Gradient a, while t == 1 has this packet return the properties
of Gradient b.
A t somewhere between 0..1 returns properties via this
GradientPacket's getters that represent the mixture of the respective
property from a & b at a ratio where t is interpreted as
a percentage between a..b.
Implementation
final double t;