IC Python API:Basic Math
From Reallusion Wiki!
- Main article: RL Python Samples.
This article will go over some basic math formulae for common numerical operations.
Required Modules
We'll need the standard Reallusion Python API to access the RMath class to perform certain types of calculations.
import RLPy
Lerp
Linearly interpolates between a and b by t.
def lerp(a, b, t):
return a + (b-a) * RLPy.RMath.Clamp(t, 0, 1)
Examples
print(lerp(25, 100, 0.5)) # 62.5
print(lerp(0, 50, 0.25)) # 12.5
Inverse Lerp
Calculates the linear parameter t that produces the interpolant value within the range [a, b].
def inverse_lerp(a, b, value):
if a != b:
return RLPy.RMath.Clamp((value - a) / (b - a), 0, 1)
return 0
Examples
print(inverse_lerp(0, 100, 50)) # 0.5
print(inverse_lerp(0, 3, 0.345)) # 0.11500000208616257
Repeat
Loops the value t, so that it is never larger than length and never smaller than 0.
def repeat(t, length):
return RLPy.RMath.Clamp(t - RLPy.RMath.Floor(t / length) * length, 0, length)
Examples
print(repeat(24, 10)) # 4
print(repeat(3, 12)) # 3
Ping Pong
PingPongs the value t, so that it is never larger than length and never smaller than 0.
def pingpong(t, length):
t = repeat(t, length * 2)
return length - abs(t-length)
Examples
print(pingpong(-150, 10)) # 10
print(pingpong(4, 1)) # 0
print(pingpong(30, 20)) # 10
