public void CanInsersectPolygon_Square_NearTopRight()
{
// Arrange
var points = new List<Vector>() { new Vector(0, 0, 0), new Vector(1, 0, 0), new Vector(1, 1, 0), new Vector(0, 1, 0) };
var poly = new Polygon(points, new Vector(0, 0, 1));
var ray = new Ray() { Start = new Vector(0.9, 0.9, 0.5), Direction = new Vector(0, 0, -1) };
// Act
var isect = poly.Intersect(ray);
// Assert
Assert.NotNull(isect);
Assert.AreEqual(0.5, isect.Distance);
Assert.AreEqual(poly, isect.Element);
}
public void CanFindPointOfIntersection()
{
// Arrange
var points = new List<Vector>() { new Vector(0, 0, 0), new Vector(1, 0, 0), new Vector(1, 1, 0), new Vector(0, 1, 0) };
var poly = new Polygon(points, new Vector(0, 0, 1));
var ray = new Ray() { Start = new Vector(0.5, 0.5, 0.5), Direction = new Vector(0, 0, -1) };
// Act
var isect = poly.GetPointOfIntersectionWithPlane(ray);
// Assert
Assert.NotNull(isect);
Assert.AreEqual(0.5, isect.X);
Assert.AreEqual(0.5, isect.Y);
}
public void CanFailToInsersectTheBackFaceOfAPolygon()
{
// Arrange
var points = new List<Vector>() { new Vector(0, 0, 0), new Vector(1, 0, 0), new Vector(1, 1, 0), new Vector(0, 1, 0) };
var poly = new Polygon(points, new Vector(0, 0, 1));
var ray = new Ray() { Start = new Vector(0.5, 0.5, -0.5), Direction = new Vector(0, 0, 1) };
// Act
var isect = poly.Intersect(ray);
// Assert
Assert.IsNull(isect);
}
public void CanFailToIntersectPlaneWithParallelRay()
{
// Arrange
var points = new List<Vector>() { new Vector(0, 0, 0), new Vector(1, 0, 0), new Vector(1, 1, 0), new Vector(0, 1, 0) };
var poly = new Polygon(points, new Vector(0, 0, 1));
var ray = new Ray() { Start = new Vector(1, 0, 0.5), Direction = new Vector(1, 0, 0) };
// Act
var isect = poly.GetPointOfIntersectionWithPlane(ray);
// Assert
Assert.IsNull(isect);
}
public void CanFailToInsersectPolygon_Square_NegativeMiss()
{
// Arrange
var points = new List<Vector>() { new Vector(0, 0, 0), new Vector(1, 0, 0), new Vector(1, 1, 0), new Vector(0, 1, 0) };
var poly = new Polygon(points, new Vector(0, 0, 1));
var ray = new Ray() { Start = new Vector(-0.5, 0.5, 0.5), Direction = new Vector(0, 0, -1) };
// Act
var isect = poly.Intersect(ray);
// Assert
Assert.IsNull(isect);
}