public FloatColour Shade(Tracer tracer, Ray tRay, float fDistance, int nDepth)
{
// declare return colour
FloatColour tColour = new FloatColour(0, 0, 0);
// get surface normal at point of intersection
Vector3 tIntersection = tRay.Position + tRay.Direction * fDistance;
Vector3 tNormal = CalculateNormal(tIntersection);
// calculate reflected ray
Ray tReflectedRay;
tReflectedRay.Direction = Vector3.Reflect(tRay.Direction, tNormal);
tReflectedRay.Position = tIntersection;
// add lighting components
foreach (Light light in tracer.Scene.Lights)
{
// get vector from surface to light
Vector3 tSurfaceToLight = light.GetDirectionToLight(tIntersection);
float fDistanceToLight = tSurfaceToLight.Length();
tSurfaceToLight.X /= fDistanceToLight;
tSurfaceToLight.Y /= fDistanceToLight;
tSurfaceToLight.Z /= fDistanceToLight;
// check whether point is in shadow
Ray tRayToLight;
tRayToLight.Position = tIntersection;
tRayToLight.Direction = tSurfaceToLight;
float fLightFactor;
if (tracer.IsShadowed(this, tRayToLight, fDistanceToLight))
{
// shadowed - little bit of ambient light
fLightFactor = 0.1f;
}
else
{
// get amount of light diffuse at intersection point
fLightFactor = Vector3.Dot(tSurfaceToLight, tNormal);
if (fLightFactor < 0)
{
fLightFactor = 0;
}
}
// calculate specular component
float fSpecular = Vector3.Dot(tRayToLight.Direction, tReflectedRay.Direction);
if (fSpecular > 0)
{
float Shininess = 100.0f;
float SpecularCoefficient = 1.0f;
fSpecular = (float)Math.Pow(fSpecular, Shininess) * SpecularCoefficient;
}
else
{
fSpecular = 0;
}
// add light effect to colour
tColour += (Material.GetColour(tIntersection) * fLightFactor + new FloatColour(fSpecular)) * light.Colour;
}
// calculate reflection colour (if needed)
if (Reflectivity != 0)
{
// calculate the reflected colour
FloatColour tReflectedColour = tracer.TraceRay(this, tReflectedRay, nDepth + 1);
// calculate total colour components
tColour += tReflectedColour * Reflectivity;
}
if (tColour.R > 255)
{
tColour.R = 255;
}
if (tColour.G > 255)
{
tColour.G = 255;
}
if (tColour.B > 255)
{
tColour.B = 255;
}
return(tColour);
}
public FloatColour Shade(Tracer tracer, Ray tRay, float fDistance, int nDepth)
{
// declare return colour
FloatColour tColour = new FloatColour(0, 0, 0);
// get surface normal at point of intersection
Vector3 tIntersection = tRay.Position + tRay.Direction * fDistance;
Vector3 tNormal = CalculateNormal(tIntersection);
// calculate reflected ray
Ray tReflectedRay;
tReflectedRay.Direction = Vector3.Reflect(tRay.Direction, tNormal);
tReflectedRay.Position = tIntersection;
// add lighting components
foreach (Light light in tracer.Scene.Lights)
{
// get vector from surface to light
Vector3 tSurfaceToLight = light.GetDirectionToLight(tIntersection);
float fDistanceToLight = tSurfaceToLight.Length();
tSurfaceToLight.X /= fDistanceToLight;
tSurfaceToLight.Y /= fDistanceToLight;
tSurfaceToLight.Z /= fDistanceToLight;
// check whether point is in shadow
Ray tRayToLight;
tRayToLight.Position = tIntersection;
tRayToLight.Direction = tSurfaceToLight;
float fLightFactor;
if (tracer.IsShadowed(this, tRayToLight, fDistanceToLight))
{
// shadowed - little bit of ambient light
fLightFactor = 0.1f;
}
else
{
// get amount of light diffuse at intersection point
fLightFactor = Vector3.Dot(tSurfaceToLight, tNormal);
if (fLightFactor < 0) fLightFactor = 0;
}
// calculate specular component
float fSpecular = Vector3.Dot(tRayToLight.Direction, tReflectedRay.Direction);
if (fSpecular > 0)
{
float Shininess = 100.0f;
float SpecularCoefficient = 1.0f;
fSpecular = (float) Math.Pow(fSpecular, Shininess) * SpecularCoefficient;
}
else
{
fSpecular = 0;
}
// add light effect to colour
tColour += (Material.GetColour(tIntersection) * fLightFactor + new FloatColour(fSpecular)) * light.Colour;
}
// calculate reflection colour (if needed)
if (Reflectivity != 0)
{
// calculate the reflected colour
FloatColour tReflectedColour = tracer.TraceRay(this, tReflectedRay, nDepth + 1);
// calculate total colour components
tColour += tReflectedColour * Reflectivity;
}
if (tColour.R > 255) tColour.R = 255;
if (tColour.G > 255) tColour.G = 255;
if (tColour.B > 255) tColour.B = 255;
return tColour;
}
