/// <summary>
/// The Phong Shader uses the Phong Reflection model to generate colors.
/// https://en.wikipedia.org/wiki/Phong_reflection_model
/// </summary>
/// <param name="Material">Surface material.</param>
/// <param name="Ambient">Ambient intensity.</param>
/// <param name="LightSources">Light sources.</param>
public PhongShader(PhongMaterial Material, PhongIntensity Ambient,
params PhongLightSource[] LightSources)
{
this.ambientReflectionConstantFront = Material.AmbientReflectionConstantFront;
this.diffuseReflectionConstantFront = Material.DiffuseReflectionConstantFront;
this.specularReflectionConstantFront = Material.SpecularReflectionConstantFront;
this.shininessFront = Material.ShininessFront;
this.ambientReflectionConstantBack = Material.AmbientReflectionConstantBack;
this.diffuseReflectionConstantBack = -Material.DiffuseReflectionConstantBack;
this.specularReflectionConstantBack = Material.SpecularReflectionConstantBack;
this.shininessBack = Material.ShininessBack;
this.distance = 0;
this.sources = LightSources;
this.nrSources = LightSources.Length;
if (this.nrSources == 1)
{
this.source = LightSources[0];
this.sourcePosition = this.source.TransformedPosition;
PhongIntensity I = this.source.Diffuse;
this.sourceDiffuseRed = I.Red;
this.sourceDiffuseGreen = I.Green;
this.sourceDiffuseBlue = I.Blue;
this.sourceDiffuseAlpha = I.Alpha;
I = this.source.Specular;
this.sourceSpecularRed = I.Red;
this.sourceSpecularGreen = I.Green;
this.sourceSpecularBlue = I.Blue;
this.sourceSpecularAlpha = I.Alpha;
}
this.ambientRedFront = this.ambientReflectionConstantFront * Ambient.Red;
this.ambientGreenFront = this.ambientReflectionConstantFront * Ambient.Green;
this.ambientBlueFront = this.ambientReflectionConstantFront * Ambient.Blue;
this.ambientAlphaFront = this.ambientReflectionConstantFront * Ambient.Alpha;
this.ambientRedBack = this.ambientReflectionConstantBack * Ambient.Red;
this.ambientGreenBack = this.ambientReflectionConstantBack * Ambient.Green;
this.ambientBlueBack = this.ambientReflectionConstantBack * Ambient.Blue;
this.ambientAlphaBack = this.ambientReflectionConstantBack * Ambient.Alpha;
}
/// <summary>
/// The Phong Shader uses the Phong Reflection model to generate colors.
/// https://en.wikipedia.org/wiki/Phong_reflection_model
/// </summary>
/// <param name="Material">Surface material.</param>
/// <param name="Ambient">Ambient intensity.</param>
/// <param name="LightSources">Light sources.</param>
public PhongShader(PhongMaterial Material, PhongIntensity Ambient,
params PhongLightSource[] LightSources)
{
this.material = Material;
this.ambient = Ambient;
this.sources = LightSources;
this.ambientReflectionConstant = Material.AmbientReflectionConstant;
this.diffuseReflectionConstant = Material.DiffuseReflectionConstant;
this.specularReflectionConstant = Material.SpecularReflectionConstant;
this.hasSpecularReflectionConstant = this.specularReflectionConstant != 0;
this.shininess = Material.Shininess;
this.nrSources = LightSources.Length;
this.singleSource = this.nrSources == 1;
if (this.singleSource)
{
this.source = LightSources[0];
this.sourcePosition = this.source.Position;
PhongIntensity I = this.source.Diffuse;
this.sourceDiffuseRed = I.Red;
this.sourceDiffuseGreen = I.Green;
this.sourceDiffuseBlue = I.Blue;
this.sourceDiffuseAlpha = I.Alpha;
I = this.source.Specular;
this.sourceSpecularRed = I.Red;
this.sourceSpecularGreen = I.Green;
this.sourceSpecularBlue = I.Blue;
this.sourceSpecularAlpha = I.Alpha;
}
this.ambientRed = this.ambientReflectionConstant * Ambient.Red;
this.ambientGreen = this.ambientReflectionConstant * Ambient.Green;
this.ambientBlue = this.ambientReflectionConstant * Ambient.Blue;
this.ambientAlpha = this.ambientReflectionConstant * Ambient.Alpha;
if (this.ambientAlpha < 255 ||
this.sourceDiffuseAlpha < 255 ||
this.sourceSpecularAlpha < 255)
{
this.opaque = false;
}
else
{
this.opaque = true;
foreach (PhongLightSource Source in this.sources)
{
if (!Source.Opaque)
{
this.opaque = false;
break;
}
}
}
}