carpaint_basic.sl

[index]

7th November 2008   3:18pm 35sec
P:\~SCAD\Renderman1\shader_src\carpaint_basic.sl

carpaint basic with basic Spec and Rough Spec

surface
carpaint_basic(
                color inputcolor = color (0.337,0.521,0.933);
                float Kd = .6;
                
                float refLevel = 0.8;                //reflection layer settings
                color upperClamp = 0.9;
                float refShellacOffset = 0.0;
                
                color shellacLevel = 0.6;             //"shellac" spec settings
                float shellacRoughness = 0.2;
                
                float paintChipTiling = 1000;        //"rough spec" settings
                float specRoughnessMult = 1;
                float K_RoughGlowSpecMult = 0.4;)
  
{
//set clamping values
color minC = color(0,0,0);
color maxC = color(1,1,1);
  
//set up normals, vectors etc
normal    n = normalize(N);
vector i = normalize(-I);
normal    nf = faceforward(n, I);
float fr = abs(n.normalize(I)); //calc facing ratio
  
color diffuseValue = Kd * diffuse(nf); //add in some diffuse
color finalDiffuse = inputcolor * fr * diffuseValue;
vector rRay = reflect(i*N,N); //get reflected vector
color calcEnvColor = environment("uffizi.tex", rRay); //use the env function to calc env reflection
color envColor = color clamp(color calcEnvColor, minC, upperClamp); //clamp it
  
color calcRefShellac = (refLevel * envColor * (1-fr)) - refShellacOffset; //shellac layer calc
color finalRefShellac = color clamp(color calcRefShellac, minC, maxC); //clamp it
  
//"shellac" layer:
color specShellac = specular(nf, i, shellacRoughness);
color finalSpecShellac = specShellac * shellacLevel * fr;
  
//"rough spec" layer:
float proceduralRoughness = noise(s*paintChipTiling,t*paintChipTiling);
color roughSpec = specular(nf, i, proceduralRoughness / specRoughnessMult);
color clampedRoughSpec = color clamp(color roughSpec, minC, maxC);
color finalRoughSpec = clampedRoughSpec * fr * K_RoughGlowSpecMult;
  
Oi = Os;
Ci = Oi * Cs * finalDiffuse + finalRefShellac + finalSpecShellac + finalRoughSpec; //final maths
}