public void TestFromAngle()
{
AssertAreEqual(new UnitVector(1, 0), UnitVector.FromAngle(0));
AssertAreEqual(new UnitVector(0, 1), UnitVector.FromAngle(Math.PI / 2));
AssertAreEqual(new UnitVector(-1, 0), UnitVector.FromAngle(Math.PI));
AssertAreEqual(new UnitVector(0, -1), UnitVector.FromAngle((Math.PI / 2) * 3));
AssertAreEqual(new UnitVector(1, 0), UnitVector.FromAngle(Math.PI * 2));
AssertAreEqual(new UnitVector(0, 1), UnitVector.FromAngle(Math.PI * 2 + Math.PI / 2));
AssertAreEqual(new UnitVector(0, -1), UnitVector.FromAngle(-Math.PI / 2));
AssertAreEqual(new UnitVector(-1, 0), UnitVector.FromAngle(-Math.PI));
AssertAreEqual(new UnitVector(0, 1), UnitVector.FromAngle(-(Math.PI / 2) * 3));
AssertAreEqual(new UnitVector(1, 0), UnitVector.FromAngle(-Math.PI * 2));
AssertAreEqual(new UnitVector(0, -1), UnitVector.FromAngle(-Math.PI * 2 - Math.PI / 2));
}
public void TestSignedAngle()
{
var u = (new Vector(1, 0.5)).Unit;
var a = u.ToAngle();
AssertAreEqual(u, UnitVector.FromAngle(a));
u = (new Vector(1, -0.5)).Unit;
a = u.ToAngle();
AssertAreEqual(u, UnitVector.FromAngle(a));
u = (new Vector(-1, 0.5)).Unit;
a = u.ToAngle();
AssertAreEqual(u, UnitVector.FromAngle(a));
u = (new Vector(-1, -0.5)).Unit;
a = u.ToAngle();
AssertAreEqual(u, UnitVector.FromAngle(a));
}
public void TestRotate()
{
var pt1 = new Point(1, 1);
var pt2 = new Point(2, 2);
var pt1_1 = pt1.Rotate(UnitVector.FromAngle(Math.PI / 4), Point.Zero);
var pt2_1 = pt2.Rotate(UnitVector.FromAngle(Math.PI / 4), Point.Zero);
var a1 = (pt2_1 - pt1_1).Unit.ToAngle();
var pt1_2 = pt1.Rotate(UnitVector.FromAngle(Math.PI / 8), Point.Zero);
var pt2_2 = pt2.Rotate(UnitVector.FromAngle(Math.PI / 8), Point.Zero);
pt2_2 = pt2_2.Rotate(UnitVector.FromAngle(Math.PI / 8), pt1_2);
var a2 = (pt2_2 - pt1_2).Unit.ToAngle();
Assert.AreEqual(a1, a2, Tol);
}