private static Lighting GetIntensity(IMaterial material, Tuple4 lightDirection, double intensity, Tuple4 eyeVector, Tuple4 pointOnSurface, Tuple4 surfaceNormal)
{
var diffuse = 0.0;
var specular = 0.0;
var cosine = Tuple4.DotProduct(lightDirection, surfaceNormal);
if (cosine >= 0)
{
diffuse = cosine * material.Diffuse;
if (material.IsShining())
{
// var reflected = Tuple4.Subtract(Tuple4.Scale(surfaceNormal, 2 * Tuple4.DotProduct(surfaceNormal, lightDirection)), lightDirection);
var reflected = Tuple4.Reflect(Tuple4.Negate(lightDirection), surfaceNormal);
var reflectedDotDir = Tuple4.DotProduct(reflected, eyeVector);
if (reflectedDotDir > 0)
{
specular = material.Specular * Math.Pow(reflectedDotDir / (reflected.Length() * eyeVector.Length()), material.Shininess);
}
}
}
return(diffuse, specular, intensity);
}
public void TupleNegateTest()
{
var t1 = new Tuple4(1, 7, 3, TupleFlavour.Vector);
var expected = new Tuple4(-1, -7, -3, TupleFlavour.Vector);
Assert.Equal(expected, Tuple4.Negate(t1));
}
public void Then_scale_scalar(string a, double t1, double t2, double t3, double t4)
{
var c = Tuple4.Negate(cache[a]);
Assert.True(Constants.EpsilonCompare(t1, c.X));
Assert.True(Constants.EpsilonCompare(t2, c.Y));
Assert.True(Constants.EpsilonCompare(t3, c.Z));
Assert.True(Constants.EpsilonCompare(t4, c.W));
}
public virtual HitResult[] AllHits(Tuple4 origin, Tuple4 dir)
{
var intersections = GetIntersections(new Ray(origin, dir));
if (intersections == null)
{
return(new HitResult[] { HitResult.NoHit });
}
var result = new HitResult[intersections.Length];
for (int i = 0; i < intersections.Length; ++i)
{
var figure = intersections[i].figure;
var distance = intersections[i].t;
var pointOnSurface = Tuple4.Geometry3D.MovePoint(origin, dir, distance); // orig + dir*dist
// TODO: Remove this cast to BaseFigure
(var surfaceNormal, var objectPoint) = ((BaseFigure)figure).GetTransformedNormal(figure, pointOnSurface, intersections[i].u, intersections[i].v);
var eyeVector = Tuple4.Negate(dir);
var isInside = false;
if (Tuple4.DotProduct(surfaceNormal, eyeVector) < 0)
{
isInside = true;
surfaceNormal = Tuple4.Negate(surfaceNormal);
}
var pointOverSurface = Tuple4.Add(pointOnSurface, Tuple4.Scale(surfaceNormal, Constants.Epsilon));
var pointUnderSurface = Tuple4.Subtract(pointOnSurface, Tuple4.Scale(surfaceNormal, Constants.Epsilon));
var reflectionVector = Tuple4.Reflect(dir, surfaceNormal);
result[i] = new HitResult(true,
figure,
distance,
intersections[i].u,
intersections[i].v,
objectPoint,
pointOnSurface,
pointOverSurface,
pointUnderSurface,
surfaceNormal,
eyeVector,
reflectionVector,
isInside);
}
return(result);
}