Hopefully this is properly implemented and properly named. On the other
hand, having length everywhere (vectors, quaternions, complex numbers)
and norm only at one place is inconsistent.
It's now possible to conveniently transform 2D vectors and points with
3x3 matrices and 3D vectors/points with 4x4 matrices. Previous most
low-level solution:
Matrix4 m;
Vector3 v;
Vector3 a = (m*Vector4(v, 1.0f)).xyz();
Vector4 b = (m*Vector4(v, 0.0f)).xyz();
Another, more generalized solution for points was with Point2D/Point3D,
adding a lot of confusion (what is that class and what does .vector()?):
Vector3 a = (m*Point3D(v)).vector();
And the worst solution was with generic 2D/3D code (WTF!):
auto a = (m*typename DimensionTraits::PointType(v)).vector();
Now it is just this, similar for both dimensions:
Vector3 a = m.transformPoint(v);
Vector3 b = m.transformVector(v);
Note that transformation three-component vectors with 3x3 matrices or
four-component vectors with 4x4 matrices is easy enough so it doesn't
need any special convenience functions whatsoever:
Vector3 c = m.rotation()*v;
Vladimír Vondruš