NAME
lerp - returns linear interpolation of two scalars or vectors based on a weight
SYNOPSIS
float lerp(float a, float b, float w); float1 lerp(float1 a, float1 b, float1 w); float2 lerp(float2 a, float2 b, float2 w); float3 lerp(float3 a, float3 b, float3 w); float4 lerp(float4 a, float4 b, float4 w); float1 lerp(float1 a, float1 b, float w); float2 lerp(float2 a, float2 b, float w); float3 lerp(float3 a, float3 b, float w); float4 lerp(float4 a, float4 b, float w); half lerp(half a, half b, half w); half1 lerp(half1 a, half1 b, half1 w); half2 lerp(half2 a, half2 b, half2 w); half3 lerp(half3 a, half3 b, half3 w); half4 lerp(half4 a, half4 b, half4 w); half1 lerp(half1 a, half1 b, half w); half2 lerp(half2 a, half2 b, half w); half3 lerp(half3 a, half3 b, half w); half4 lerp(half4 a, half4 b, half w); fixed lerp(fixed a, fixed b, fixed w); fixed1 lerp(fixed1 a, fixed1 b, fixed1 w); fixed2 lerp(fixed2 a, fixed2 b, fixed2 w); fixed3 lerp(fixed3 a, fixed3 b, fixed3 w); fixed4 lerp(fixed4 a, fixed4 b, fixed4 w); fixed1 lerp(fixed1 a, fixed1 b, fixed w); fixed2 lerp(fixed2 a, fixed2 b, fixed w); fixed3 lerp(fixed3 a, fixed3 b, fixed w); fixed4 lerp(fixed4 a, fixed4 b, fixed w);PARAMETERS
- a
Vector or scalar to weight; returned with w is one.
- b
Vector or scalar to weight; returned with w is zero.
- w
Vector or scalar weight.
DESCRIPTION
Returns the linear interpolation of a and b based on weight w.
a and b are either both scalars or both vectors of the same length. The weight w may be a scalar or a vector of the same length as a and b. w can be any value (so is not restricted to be between zero and one); if w has values outside the [0,1] range, it actually extrapolates.
lerp returns a when w is one and returns b when w is zero.
REFERENCE IMPLEMENTATION
lerp for float3 vectors for a and b and a float w could be implemented like this:
float3 lerp(float3 a, float3 b, float w) { return a + w*(b-a); }PROFILE SUPPORT
lerp is supported in all profiles.
SEE ALSO