From aea9ceca71b59358248be94fdf272fd4791ca990 Mon Sep 17 00:00:00 2001
From: Mikko Rasa <tdb@tdb.fi>
Date: Tue, 4 Jun 2019 14:11:45 +0300
Subject: [PATCH] Add more public methods to Transform

---
 source/transform.cpp | 42 ++++++++++++++++++++++++++++++++----------
 source/transform.h   |  4 ++++
 2 files changed, 36 insertions(+), 10 deletions(-)

diff --git a/source/transform.cpp b/source/transform.cpp
index 9660c2c4..4b67bf91 100644
--- a/source/transform.cpp
+++ b/source/transform.cpp
@@ -9,6 +9,23 @@ Transform::Transform():
 	scale(1.0f, 1.0f, 1.0f)
 { }
 
+Transform Transform::from_matrix(const Matrix &matrix)
+{
+	Transform trn;
+	trn.position = matrix.column(3).slice<3>(0);
+
+	trn.euler.z = Geometry::atan2<float>(matrix(1, 0), matrix(0, 0));
+	Matrix m = Matrix::rotation(-trn.euler.z, Vector3(0.0f, 0.0f, 1.0f))*matrix;
+	trn.euler.y = Geometry::atan2<float>(m(2, 0), m(0, 0));
+	m = Matrix::rotation(-trn.euler.y, Vector3(0.0f, 1.0f, 0.0f))*m;
+	trn.euler.x = Geometry::atan2<float>(m(2, 1), m(1, 1));
+	m = Matrix::rotation(-trn.euler.x, Vector3(1.0f, 0.0f, 0.0f))*m;
+
+	trn.scale = Vector3(m(0, 0), m(1, 1), m(2, 2));
+
+	return trn;
+}
+
 void Transform::set_position(const Vector3 &p)
 {
 	position = p;
@@ -19,6 +36,16 @@ void Transform::set_euler(const AngleVector3 &e)
 	euler = e;
 }
 
+void Transform::set_rotation(const Angle &angle, const Vector3 &axis)
+{
+	euler = from_matrix(Matrix::rotation(angle, axis)).euler;
+}
+
+void Transform::set_scale(float s)
+{
+	set_scale(Vector3(s, s, s));
+}
+
 void Transform::set_scale(const Vector3 &s)
 {
 	scale = s;
@@ -48,32 +75,27 @@ Transform::Loader::Loader(Transform &t):
 
 void Transform::Loader::position(float x, float y, float z)
 {
-	obj.position = Vector3(x, y, z);
+	obj.set_position(Vector3(x, y, z));
 }
 
 void Transform::Loader::euler(float x, float y, float z)
 {
-	obj.euler = AngleVector3(Angle::from_degrees(x), Angle::from_degrees(y), Angle::from_degrees(z));
+	obj.set_euler(AngleVector3(Angle::from_degrees(x), Angle::from_degrees(y), Angle::from_degrees(z)));
 }
 
 void Transform::Loader::rotation(float a, float x, float y, float z)
 {
-	Matrix matrix = Matrix::rotation(Angle::from_degrees(a), Vector3(x, y, z));
-	obj.euler.z = Geometry::atan2<float>(matrix(1, 0), matrix(0, 0));
-	matrix = Matrix::rotation(-obj.euler.z, Vector3(0.0f, 0.0f, 1.0f))*matrix;
-	obj.euler.y = Geometry::atan2<float>(matrix(2, 0), matrix(0, 0));
-	matrix = Matrix::rotation(-obj.euler.y, Vector3(0.0f, 1.0f, 0.0f))*matrix;
-	obj.euler.x = Geometry::atan2<float>(matrix(2, 1), matrix(1, 1));
+	obj.set_rotation(Angle::from_degrees(a), Vector3(x, y, z));
 }
 
 void Transform::Loader::scale_uniform(float s)
 {
-	obj.scale = Vector3(s, s, s);
+	obj.set_scale(s);
 }
 
 void Transform::Loader::scale(float x, float y, float z)
 {
-	obj.scale = Vector3(x, y, z);
+	obj.set_scale(Vector3(x, y, z));
 }
 
 } // namespace GL
diff --git a/source/transform.h b/source/transform.h
index ee821ce1..01c783bd 100644
--- a/source/transform.h
+++ b/source/transform.h
@@ -39,8 +39,12 @@ private:
 public:
 	Transform();
 
+	static Transform from_matrix(const Matrix &);
+
 	void set_position(const Vector3 &);
 	void set_euler(const AngleVector3 &);
+	void set_rotation(const Angle &, const Vector3 &);
+	void set_scale(float);
 	void set_scale(const Vector3 &);
 	const Vector3 &get_position() const { return position; }
 	const AngleVector3 &get_euler() const { return euler; }
-- 
2.43.0