void LerpFunc(PaintJob j, int idx, ref object val, float r)
{
BrushData bd = val as BrushData;
var s = j.stream;
Vector3 pos = j.GetPosition(idx);
pos = j.renderer.localToWorldMatrix.MultiplyPoint(pos);
pos.x *= bd.frequency;
pos.y *= bd.frequency;
pos.z *= bd.frequency;
float noise = 0.5f * (0.5f * ShaderLib.VertexPainter.SimplexNoise.Noise.Generate(pos.x, pos.y, pos.z) + 0.5f);
noise += 0.25f * (0.5f * ShaderLib.VertexPainter.SimplexNoise.Noise.Generate(pos.y * 2.031f, pos.z * 2.031f, pos.x * 2.031f) + 0.5f);
noise += 0.25f * (0.5f * ShaderLib.VertexPainter.SimplexNoise.Noise.Generate(pos.z * 4.01f, pos.x * 4.01f, pos.y * 4.01f) + 0.5f);
noise *= bd.amplitude;
// lerp the noise in
Color c = s.colors[idx];
c.r = Mathf.Lerp(c.r, noise, r);
c.g = Mathf.Lerp(c.g, noise, r);
c.b = Mathf.Lerp(c.b, noise, r);
s.colors[idx] = c;
}
