public static Color ColorInfo2Color(ColorInfo color)
{
return(Color.FromArgb((int)(color.R * 255), (int)(color.G * 255), (int)(color.B * 255)));
}
public static Color PhongeIllumination(Vector <double> position, Vector <double> normal,
ColorInfo colorInfo, SurfaceInfo surface, List <Light> lights)
{
ColorInfo outcome = new ColorInfo {
R = 0, G = 0, B = 0
};
//ambient
outcome.R += colorInfo.R * surface.Ka;
outcome.G += colorInfo.G * surface.Ka;
outcome.B += colorInfo.B * surface.Ka;
foreach (var light in lights)
{
if (!light.IsOn)
{
continue;
}
double spotlightFactor = 1;
var l = light.CalculateLVector(position);
if (light.IsSpotLight)
{
var cos = (-light.ProcessedDirection).DotProduct(l);
if (cos > 0)
{
spotlightFactor = Math.Pow(cos, light.P);
}
else
{
spotlightFactor = 0;
}
}
//diffuse
var lightNormalAngle = normal.DotProduct(l);
var diffuseR = surface.Kd * lightNormalAngle * spotlightFactor;
if (lightNormalAngle < 0)
{
continue;
}
outcome.R += colorInfo.R * diffuseR;
outcome.G += colorInfo.G * diffuseR;
outcome.B += colorInfo.B * diffuseR;
//sepcular
var v = (-position).Normalize(2);
var r = 2 * lightNormalAngle * normal - l;
r = r.Normalize(2);
var cameraRAngle = r.DotProduct(v);
if (cameraRAngle < 0)
{
continue;
}
var specularR = surface.Ks * Math.Pow(cameraRAngle, surface.N_shiny) * spotlightFactor;
outcome.R += specularR;
outcome.G += specularR;
outcome.B += specularR;
}
if (outcome.R > 1)
{
outcome.R = 1;
}
if (outcome.G > 1)
{
outcome.G = 1;
}
if (outcome.B > 1)
{
outcome.B = 1;
}
return(ColorInfo2Color(outcome));
}
