public void Trivial()
{
// Convention is UnitZ forward, UnitX right, UnitY up in local space.
var mat = FMatrix4x4.RotationLookAtRH(Vector3.Zero, Vector3.UnitZ, Vector3.UnitY);
AssertAlike(mat.Transform(Vector3.UnitZ), Vector3.UnitZ);
AssertAlike(mat.Transform(Vector3.UnitX), Vector3.UnitX);
AssertAlike(mat.Transform(Vector3.UnitY), Vector3.UnitY);
}
public void RotationLookAt() => Trials(1000, r => {
var a = RandomVector3(r);
var b = RandomVector3(r);
var c = RandomVector3(r);
// Rotation lookat RH is lookat LH with flipped Z
var la = Matrix4x4.CreateLookAt(b, a, c);
// And additionally, no translation
la.M41 = la.M42 = la.M43 = 0.0f;
// LookAt is meant for camera. Does the opposite motion of what we want,
// so invert (orthonormal matrix, so transpose equivalent)
la = Matrix4x4.Transpose(la);
AssertAlike(FMatrix4x4.RotationLookAtRH(a, b, c), la);
});
public void Turn111()
{
// Convention is UnitZ forward, UnitX right, UnitY up in local space.
var mat = FMatrix4x4.RotationLookAtRH(Vector3.Zero, Vector3.One, Vector3.UnitY);
output.WriteLine(mat.ToStringNewline());
AssertAlike(mat.Transform(Vector3.UnitZ), Vec3(1, 1, 1).Normalize());
output.WriteLine(mat.Transform(Vector3.UnitY).ToString());
Assert.True(mat.Transform(Vector3.UnitY).Dot(Vector3.UnitX) < 0);
Assert.True(mat.Transform(Vector3.UnitY).Dot(Vector3.UnitY) > 0);
Assert.True(mat.Transform(Vector3.UnitY).Dot(Vector3.UnitZ) < 0);
output.WriteLine(mat.Transform(Vector3.UnitX).ToString());
Assert.True(mat.Transform(Vector3.UnitX).Dot(Vector3.UnitX) > 0);
Assert.True(mat.Transform(Vector3.UnitX).Dot(Vector3.UnitY) >= 0);
Assert.True(mat.Transform(Vector3.UnitX).Dot(Vector3.UnitZ) < 0);
}