Function B2Vec2Mat22Mul

CommonB2Math.go:511–513

Multiply a matrix times a vector. If a rotation matrix is provided, then this transforms the vector from one frame to another.

(A B2Mat22, v B2Vec2)

/// Multiply a matrix times a vector. If a rotation matrix is provided,
/// then this transforms the vector from one frame to another.
func B2Vec2Mat22Mul(A B2Mat22, v B2Vec2) B2Vec2 {
	return MakeB2Vec2(A.Ex.X*v.X+A.Ey.X*v.Y, A.Ex.Y*v.X+A.Ey.Y*v.Y)
}

/// Multiply a matrix transpose times a vector. If a rotation matrix is provided,
/// then this transforms the vector from one frame to another (inverse transform).