public Color Lighting(RTObject obj, ILight light, Point position, Vector eyev, Vector normalv, double intensity)
{
Color color;
if (Pattern != null)
{
color = Pattern.PatternAtObject(obj, position);
}
else if (obj.Parent != null)
{
color = obj.Parent.Material.Lighting(obj.Parent, light, position, eyev, normalv, intensity);
}
else
{
color = Color;
}
var effectiveColor = color * light.Intensity;
var ambient = effectiveColor * Ambient;
var samples = light.SamplePoints();
Color sum = Color.Black;
foreach (var sample in samples)
{
Color diffuse;
Color specular;
var lightV = (new Vector(sample - position)).Normalize;
var lightDotNormal = lightV.Dot(normalv);
if ((lightDotNormal < 0) || intensity.IsEqual(0.0))
{
diffuse = Color.Black; // inShadow ? Color.Green : Color.Black;
specular = Color.Black; // inShadow ? Color.Green : Color.Black;
}
else
{
diffuse = effectiveColor * Diffuse * lightDotNormal;
var reflectV = (-lightV).Reflect(normalv);
var reflectDotEye = reflectV.Dot(eyev);
if (reflectDotEye <= 0)
{
specular = Color.Black;
}
else
{
var factor = Math.Pow(reflectDotEye, Shininess);
specular = light.Intensity * Specular * factor;
}
}
sum += diffuse;
sum += specular;
}
return(ambient + ((sum / light.Samples) * intensity));
}