public void HelperClassForProducingSphereWithGlassyMaterial_ShouldExist()
{
var s = new GlassSphere();
Assert.Equal(Matrix.Identity, s.Transform, MatrixComparer);
Assert.Equal(1.0, s.Material.Transparency);
Assert.Equal(1.5, s.Material.RefractiveIndex);
}
public void SchlickApproximationWithSmallAngleAndN2GreaterThanN1_ShouldBeSignificant()
{
var shape = new GlassSphere();
var r = new Ray(new Point(0, 0.99, -2), new Vector(0, 0, 1));
var xs = new List <Intersection> {
new Intersection(1.8589, shape)
};
var comps = xs[0].PrepareComputations(r, xs);
Assert.Equal(0.48873, comps.Schlick(), 4);
}
public void SchlickApproximationWithPerpendicularViewingAngle_ShouldBeSmall()
{
var shape = new GlassSphere();
var r = new Ray(new Point(0, 0, 0), new Vector(0, 1, 0));
var xs = new List <Intersection> {
new Intersection(-1, shape), new Intersection(1, shape)
};
var comps = xs[1].PrepareComputations(r, xs);
Assert.Equal(0.04, comps.Schlick(), 2);
}
public void SchlickApproximationUnderTotalInternalReflection_ShouldReturn1()
{
var shape = new GlassSphere();
var r = new Ray(new Point(0, 0, Math.Sqrt(2) / 2), new Vector(0, 1, 0));
var xs = new List <Intersection> {
new Intersection(-Math.Sqrt(2) / 2, shape), new Intersection(Math.Sqrt(2) / 2, shape)
};
var comps = xs[1].PrepareComputations(r, xs);
Assert.Equal(1.0, comps.Schlick());
}
public void WhenCalculatingUnderPoint_ShouldOffsetBelowTheSurface()
{
var r = new Ray(new Point(0, 0, -5), new Vector(0, 0, 1));
var shape = new GlassSphere();
shape.Transform = Transformation.Translation(0, 0, 1);
var i = new Intersection(5, shape);
var xs = new List <Intersection> {
i
};
var comps = i.PrepareComputations(r, xs);
Assert.True(comps.UnderPoint.z > EPSILON / 2);
Assert.True(comps.Point.z < comps.UnderPoint.z);
}
public void FindingN1AndN2AtVariousIntersections_ShouldWork()
{
var A = new GlassSphere();
A.Transform = Transformation.Scaling(2, 2, 2);
A.Material.RefractiveIndex = 1.5;
var B = new GlassSphere();
B.Transform = Transformation.Translation(0, 0, -0.25);
B.Material.RefractiveIndex = 2.0;
var C = new GlassSphere();
C.Transform = Transformation.Translation(0, 0, 0.25);
C.Material.RefractiveIndex = 2.5;
var r = new Ray(new Point(0, 0, -4), new Vector(0, 0, 1));
var x0 = new Intersection(2, A);
var x1 = new Intersection(2.75, B);
var x2 = new Intersection(3.25, C);
var x3 = new Intersection(4.75, B);
var x4 = new Intersection(5.25, C);
var x5 = new Intersection(6, A);
var xs = new List <Intersection> {
x0, x1, x2, x3, x4, x5
};
var comps0 = x0.PrepareComputations(r, xs);
var comps1 = x1.PrepareComputations(r, xs);
var comps2 = x2.PrepareComputations(r, xs);
var comps3 = x3.PrepareComputations(r, xs);
var comps4 = x4.PrepareComputations(r, xs);
var comps5 = x5.PrepareComputations(r, xs);
Assert.Equal(1.0, comps0.n1);
Assert.Equal(1.5, comps0.n2);
Assert.Equal(1.5, comps1.n1);
Assert.Equal(2.0, comps1.n2);
Assert.Equal(2.0, comps2.n1);
Assert.Equal(2.5, comps2.n2);
Assert.Equal(2.5, comps3.n1);
Assert.Equal(2.5, comps3.n2);
Assert.Equal(2.5, comps4.n1);
Assert.Equal(1.5, comps4.n2);
Assert.Equal(1.5, comps5.n1);
Assert.Equal(1.0, comps5.n2);
}