/**
* Framework function for debugging.
* @param traceObj
* @private
*/
#if DEBUG
static void debug(TraceObj traceObj)
{
if (debugFunction != null)
{
if (traceObj.canPrint)
{
debugFunction(traceObj.toString());
}
}
loggerFunction?.Invoke(traceObj);
}
bool Scatter(ref RaycastHit hit, ref Ray ray, ref TraceObj obj, out Color atten, out Ray scatter, out Color light, ref int rayCount)
{
var mat = obj.mat;
light = Color.black;
atten = default(Color);
scatter = default(Ray);
switch (mat.type)
{
case MaterialWrap.Type.Lambert:
var hitpos = hit.point;
var target = hitpos + hit.normal + Random.insideUnitSphere;
scatter = new Ray(hitpos, (target - hitpos).normalized);
atten = mat.albedo;
return(true);
case MaterialWrap.Type.Metal:
var reflect = Vector3.Reflect(ray.direction, hit.normal);
scatter = new Ray(hit.point, (reflect
+ mat.roughness * Random.insideUnitSphere).normalized); // 随机发射，模拟粗糙的表面
atten = mat.albedo;
return(Vector3.Dot(reflect, hit.normal) > 0);
case MaterialWrap.Type.Dielectric:
atten = Color.white;
float nint;
Vector3 normal;
float cosine;
if (Vector3.Dot(ray.direction, hit.normal) > 0)
{
normal = -hit.normal;
nint = mat.ri;
cosine = mat.ri * Vector3.Dot(ray.direction, hit.normal);
}
else
{
normal = hit.normal;
nint = 1 / mat.ri;
cosine = -Vector3.Dot(ray.direction, hit.normal);
}
float reflProb;
Vector3 refracted;
if (Refract(ray.direction, normal, nint, out refracted))
{
reflProb = Schlick(cosine, mat.ri);
}
else
{
reflProb = 1;
}
if (Random.Range(0, 1.0f) < reflProb)
{
scatter = new Ray(hit.point, Vector3.Reflect(ray.direction, hit.normal));
}
else
{
scatter = new Ray(hit.point, refracted.normalized);
}
break;
default:
return(false);
}
return(true);
}
