public void Hit()
{
var sphere = new Sphere();
var intersection1 = new Intersection(1, sphere);
var intersection2 = new Intersection(2, sphere);
var intersections = new Intersections(intersection1, intersection2);
Assert.Equal(intersection1, intersections.Hit());
intersection1 = new Intersection(-1, sphere);
intersection2 = new Intersection(1, sphere);
intersections = new Intersections(intersection1, intersection2);
Assert.Equal(intersection2, intersections.Hit());
intersection1 = new Intersection(-2, sphere);
intersection2 = new Intersection(-1, sphere);
intersections = new Intersections(intersection1, intersection2);
Assert.Null(intersections.Hit());
intersection1 = new Intersection(5, sphere);
intersection2 = new Intersection(7, sphere);
var intersection3 = new Intersection(-3, sphere);
var intersection4 = new Intersection(2, sphere);
intersections = new Intersections(intersection1, intersection2, intersection3, intersection4);
Assert.Equal(intersection4, intersections.Hit());
}
public void HitWhenAllDistancesNegative()
{
var s = new Sphere();
var i1 = new Intersection(-2, s);
var i2 = new Intersection(-1, s);
var xs = new Intersections(i1, i2);
var h = xs.Hit();
Assert.AreEqual(null, h);
}
public void HitWhenAllDistancesPositive()
{
var s = new Sphere();
var i1 = new Intersection(1, s);
var i2 = new Intersection(2, s);
var xs = new Intersections(i1, i2);
var h = xs.Hit();
Assert.AreEqual(i1, h);
}
public void HitIsAlwaysLowestNonNegativeIntersection()
{
var s = new Sphere();
var i1 = new Intersection(5, s);
var i2 = new Intersection(7, s);
var i3 = new Intersection(-3, s);
var i4 = new Intersection(2, s);
var xs = new Intersections(i1, i2, i3, i4);
var h = xs.Hit();
Assert.AreEqual(i4, h);
}
public void TheHitWhenAllIntersectionsHaveNegativeT()
{
var s = new Sphere();
var i1 = new Intersection(-1, s);
var i2 = new Intersection(-2, s);
var xs = new Intersections(new List <Intersection> {
i2, i1
});
var i = xs.Hit();
Assert.IsNull(i);
}
public void TheHitWhenSomeIntersectionsHaveNegativeT()
{
var s = new Sphere();
var i1 = new Intersection(-1, s);
var i2 = new Intersection(1, s);
var xs = new Intersections(new List <Intersection> {
i2, i1
});
var i = xs.Hit();
Assert.AreEqual(i2, i);
}
public void TheHitWhenAllIntersectionsHavePositiveT()
{
var s = new Sphere();
var i1 = new Intersection(1, s);
var i2 = new Intersection(2, s);
var xs = new Intersections(new List <Intersection> {
i2, i1
});
var i = xs.Hit();
Assert.AreEqual(i1, i);
}
public void LightingSpherePictureTest()
{
int size = 400;
var rayOrigin = Helper.CreatePoint(0, 0, -5);
double wallZ = 10;
double wallSize = 7;
var pixelSize = wallSize / size;
var half = wallSize / 2;
var canvas = new Canvas(size, size);
var sphere = Helper.Sphere();
sphere.Material.Pattern = new SolidPattern(new Color(1, 0.2, 1));
var light = new PointLight(Helper.CreatePoint(-10, 10, -10), Color.White);
for (int y = 0; y < size; y++)
{
double worldY = half - pixelSize * y;
for (int x = 0; x < size - 1; x++)
{
// compute the world x coordinate (left = -half, right = half)
double worldX = -half + pixelSize * x;
// describe the point on the wall that the ray will target
var position = Helper.CreatePoint(worldX, worldY, wallZ);
var ray = Helper.Ray(rayOrigin, (position - rayOrigin).Normalize());
var intersections = new Intersections();
sphere.Intersect(ref ray.Origin, ref ray.Direction, intersections);
var hit = intersections.Hit();
if (hit != null)
{
var point = ray.Position(hit.T);
var hitObject = hit.Object;
var normal = hitObject.NormalAt(point);
var eye = -ray.Direction;
var color = hitObject.Material.Lighting(light, ref point, ref eye, ref normal, 1);
canvas.SetPixel(x, y, color);
}
}
}
var tmpFile = Path.GetTempFileName();
var ppmFile = Path.ChangeExtension(tmpFile, "ppm");
canvas.SavePPM(ppmFile);
// Helper.Display(ppmFile);
File.Delete(tmpFile);
File.Delete(ppmFile);
}
public void GivenIntersectionHit_WhenAllIntersectionsHaveNegativeTimeValue_ThenReturnLowestPositiveIntersection()
{
// Arrange
var sphere = new Sphere();
var i1 = new Intersection(-2, sphere);
var i2 = new Intersection(-1, sphere);
var intersections = new Intersections(i1, i2);
// Act
var hit = intersections.Hit();
// Assert
Assert.Null(hit);
}
public void TheHitIsAllwaysTheLowestNonNegativeIntersection()
{
var s = new Sphere();
var i1 = new Intersection(5, s);
var i2 = new Intersection(7, s);
var i3 = new Intersection(-3, s);
var i4 = new Intersection(2, s);
var xs = new Intersections(new List <Intersection> {
i1, i2, i3, i4
});
var i = xs.Hit();
Assert.AreEqual(i4, i);
}
public void TestHitAllNegativeDistance()
{
var sphere = new Sphere();
var i1 = new Intersection(-1, sphere);
var i2 = new Intersection(-2, sphere);
var intersections = new Intersections
{
i2,
i1
};
Assert.IsNull(intersections.Hit()?.Shape);
}
public void TestHitNegativeDistance()
{
var sphere = new Sphere();
var i1 = new Intersection(-1, sphere);
var i2 = new Intersection(1, sphere);
var intersections = new Intersections
{
i2,
i1
};
Assert.AreEqual(i2, intersections.Hit());
}
public void GivenIntersectionHit_WhenIntersectionsHaveMixedTimeValue_ThenReturnLowestPositiveIntersection()
{
// Arrange
var sphere = new Sphere();
var i1 = new Intersection(5, sphere);
var i2 = new Intersection(7, sphere);
var i3 = new Intersection(-3, sphere);
var i4 = new Intersection(2, sphere);
var intersections = new Intersections(i1, i2, i3, i4);
// Act
var hit = intersections.Hit();
// Assert
Assert.Equal(i4, hit);
}
public void TestHitMultiple()
{
var sphere = new Sphere();
var i1 = new Intersection(5, sphere);
var i2 = new Intersection(7, sphere);
var i3 = new Intersection(-2, sphere);
var i4 = new Intersection(3, sphere);
var intersections = new Intersections
{
i1,
i2,
i3,
i4
};
Assert.AreEqual(i4, intersections.Hit());
}
private void SpherePictureTest(Matrix transform)
{
int size = 400;
var rayOrigin = Helper.CreatePoint(0, 0, -5);
double wallZ = 10;
double wallSize = 7;
var pixelSize = wallSize / size;
var half = wallSize / 2;
var canvas = new Canvas(size, size);
var color = new Color(1, 0, 0);
var sphere = Helper.Sphere();
sphere.Transform = transform;
for (int y = 0; y < size; y++)
{
double worldY = half - pixelSize * y;
for (int x = 0; x < size - 1; x++)
{
// compute the world x coordinate (left = -half, right = half)
double worldX = -half + pixelSize * x;
// describe the point on the wall that the ray will target
var position = Helper.CreatePoint(worldX, worldY, wallZ);
var r = Helper.Ray(rayOrigin, (position - rayOrigin).Normalize());
var intersections = new Intersections();
sphere.Intersect(ref r.Origin, ref r.Direction, intersections);
if (intersections.Hit() != null)
{
canvas.SetPixel(x, y, color);
}
}
}
var tmpFile = Path.GetTempFileName();
var ppmFile = Path.ChangeExtension(tmpFile, "ppm");
canvas.SavePPM(ppmFile);
// Helper.Display(ppmFile);
File.Delete(tmpFile);
File.Delete(ppmFile);
}
