public double[] ColorReflection(IMaterial material, Vector3d normal, Vector3d input, Vector3d output, ReflectionComponent comp)
{
if (!(material is PhongMaterial))
{
return(null);
}
PhongMaterial mat = (PhongMaterial)material;
int bands = mat.Color.Length;
double[] result = new double[bands];
bool viewOut = Vector3d.Dot(output, normal) > 0.0;
double coef;
if (input.Equals(Vector3d.Zero)) // ambient term only..
{
// dim ambient light if viewer is inside
coef = viewOut ? mat.Ka : (mat.Ka * mat.Kt);
for (int i = 0; i < bands; i++)
{
result[i] = coef * mat.Color[i];
}
return(result);
}
// directional light source:
input.Normalize();
double cosAlpha = Vector3d.Dot(input, normal);
bool lightOut = cosAlpha > 0.0;
double ks = mat.Ks;
double kd = mat.Kd;
double kt = mat.Kt;
Vector3d r = Vector3d.Zero;
coef = 1.0;
if (viewOut == lightOut) // viewer and source are on the same side..
{
if ((comp & ReflectionComponent.SPECULAR_REFLECTION) != 0)
{
double cos2 = cosAlpha + cosAlpha;
r = normal * cos2 - input;
if (!lightOut && // total reflection check
-cosAlpha <= mat.cosTotal)
{
if ((ks += kt) + kd > 1.0)
{
ks = 1.0 - kd;
}
}
}
}
else // opposite sides => use specular refraction
{
if ((comp & ReflectionComponent.SPECULAR_REFRACTION) != 0)
{
r = Geometry.SpecularRefraction(normal, mat.n, input);
}
coef = kt;
}
double diffuse = (comp & ReflectionComponent.DIFFUSE) == 0 ? 0.0 : coef *kd *Math.Abs(cosAlpha);
double specular = 0.0;
if (r != Vector3d.Zero)
{
double cosBeta = Vector3d.Dot(r, output);
if (cosBeta > 0.0)
{
specular = coef * ks * Arith.Pow(cosBeta, mat.H);
}
}
for (int i = 0; i < bands; i++)
{
result[i] = diffuse * mat.Color[i] + specular;
}
return(result);
}
public double[] ColorReflection( IMaterial material, Vector3d normal, Vector3d input, Vector3d output, ReflectionComponent comp )
{
if ( !(material is PhongMaterial) ) return null;
PhongMaterial mat = (PhongMaterial)material;
int bands = mat.Color.Length;
double[] result = new double[ bands ];
bool viewOut = Vector3d.Dot( output, normal ) > 0.0;
double coef;
if ( input.Equals( Vector3d.Zero ) ) // ambient term only..
{
// dim ambient light if viewer is inside
coef = viewOut ? mat.Ka : (mat.Ka * mat.Kt);
for ( int i = 0; i < bands; i++ )
result[ i ] = coef * mat.Color[ i ];
return result;
}
// directional light source:
input.Normalize();
double cosAlpha = Vector3d.Dot( input, normal );
bool lightOut = cosAlpha > 0.0;
double ks = mat.Ks;
double kd = mat.Kd;
double kt = mat.Kt;
Vector3d r = Vector3d.Zero;
coef = 1.0;
if ( viewOut == lightOut ) // viewer and source are on the same side..
{
if ( (comp & ReflectionComponent.SPECULAR_REFLECTION) != 0 )
{
double cos2 = cosAlpha + cosAlpha;
r = normal * cos2 - input;
if ( !lightOut && // total reflection check
-cosAlpha <= mat.cosTotal )
if ( (ks += kt) + kd > 1.0 )
ks = 1.0 - kd;
}
}
else // opposite sides => use specular refraction
{
if ( (comp & ReflectionComponent.SPECULAR_REFRACTION) != 0 )
r = Geometry.SpecularRefraction( normal, mat.n, input );
coef = kt;
}
double diffuse = (comp & ReflectionComponent.DIFFUSE) == 0 ? 0.0 : coef * kd * Math.Abs( cosAlpha );
double specular = 0.0;
if ( r != Vector3d.Zero )
{
double cosBeta = Vector3d.Dot( r, output );
if ( cosBeta > 0.0 )
specular = coef * ks * Arith.Pow( cosBeta, mat.H );
}
for ( int i = 0; i < bands; i++ )
result[i] = diffuse * mat.Color[i] + specular;
return result;
}
public double[] ColorReflection(Intersection intersection, Vector3d input, Vector3d output, ReflectionComponent comp)
{
return(ColorReflection(intersection.Material, intersection.Normal, input, output, comp));
}
public double[] ColorReflection( Intersection intersection, Vector3d input, Vector3d output, ReflectionComponent comp )
{
return ColorReflection( intersection.Material, intersection.Normal, input, output, comp );
}
