From d37b685df9334043a9f8170f377abf10ac1ead78 Mon Sep 17 00:00:00 2001
From: josh <josh@stepbro.wtf>
Date: Thu, 1 Feb 2024 21:02:18 -0500
Subject: [PATCH] Implement Matrix3x3 FromScale and ScaleBy

---
 include/J3ML/LinearAlgebra/Matrix3x3.h | 24 +++++----------
 include/J3ML/LinearAlgebra/Matrix4x4.h |  5 +++
 src/J3ML/LinearAlgebra/Matrix3x3.cpp   | 42 ++++++++++++++++++++++++--
 3 files changed, 53 insertions(+), 18 deletions(-)

diff --git a/include/J3ML/LinearAlgebra/Matrix3x3.h b/include/J3ML/LinearAlgebra/Matrix3x3.h
index 3596cb9..8d18501 100644
--- a/include/J3ML/LinearAlgebra/Matrix3x3.h
+++ b/include/J3ML/LinearAlgebra/Matrix3x3.h
@@ -61,16 +61,7 @@ namespace LinearAlgebra {
         void SetColumn(int i, const Vector3& vector);
         void SetAt(int x, int y, float value);
 
-        void Orthonormalize(int c0, int c1, int c2)
-        {
-            Vector3 v0 = GetColumn(c0);
-            Vector3 v1 = GetColumn(c1);
-            Vector3 v2 = GetColumn(c2);
-            Vector3::Orthonormalize(v0, v1, v2);
-            SetColumn(c0, v0);
-            SetColumn(c1, v1);
-            SetColumn(c2, v2);
-        }
+        void Orthonormalize(int c0, int c1, int c2);
 
         static Matrix3x3 LookAt(const Vector3& forward, const Vector3& target, const Vector3& localUp, const Vector3& worldUp);
 
@@ -90,8 +81,8 @@ namespace LinearAlgebra {
 
         /// Creates a new transformation matrix that scales by the given factors.
         // This matrix scales with respect to origin.
-        static Matrix3x3 Scale(float sx, float sy, float sz);
-        static Matrix3x3 Scale(const Vector3& scale);
+        static Matrix3x3 FromScale(float sx, float sy, float sz);
+        static Matrix3x3 FromScale(const Vector3& scale);
 
         /// Returns the main diagonal.
         Vector3 Diagonal() const;
@@ -124,10 +115,11 @@ namespace LinearAlgebra {
         Vector2 Transform(const Vector2& rhs) const;
         Vector3 Transform(const Vector3& rhs) const;
 
-        Vector3 operator[](int row) const
-        {
-            return Vector3{elems[row][0], elems[row][1], elems[row][2]};
-        }
+
+        Matrix3x3 ScaleBy(const Vector3& rhs);
+        Vector3 GetScale() const;
+
+        Vector3 operator[](int row) const;
 
         Vector3 operator * (const Vector3& rhs) const;
         Matrix3x3 operator * (const Matrix3x3& rhs) const;
diff --git a/include/J3ML/LinearAlgebra/Matrix4x4.h b/include/J3ML/LinearAlgebra/Matrix4x4.h
index 54d213d..5fa9bd9 100644
--- a/include/J3ML/LinearAlgebra/Matrix4x4.h
+++ b/include/J3ML/LinearAlgebra/Matrix4x4.h
@@ -118,6 +118,11 @@ namespace LinearAlgebra {
         Vector3 GetRow3(int index) const;
         Vector3 GetColumn3(int index) const;
 
+        Vector3 GetScale() const
+        {
+
+        }
+
         float &At(int row, int col);
         float At(int x, int y) const;
 
diff --git a/src/J3ML/LinearAlgebra/Matrix3x3.cpp b/src/J3ML/LinearAlgebra/Matrix3x3.cpp
index 3f32c48..0fd58d1 100644
--- a/src/J3ML/LinearAlgebra/Matrix3x3.cpp
+++ b/src/J3ML/LinearAlgebra/Matrix3x3.cpp
@@ -313,16 +313,54 @@ namespace LinearAlgebra {
     }
 
     Matrix3x3 Matrix3x3::FromRS(const Quaternion &rotate, const Vector3 &scale) {
-        return Matrix3x3(rotate) * Matrix3x3::Scale(scale);
+        return Matrix3x3(rotate) * Matrix3x3::FromScale(scale);
     }
 
     Matrix3x3 Matrix3x3::FromRS(const Matrix3x3 &rotate, const Vector3 &scale) {
-        return rotate * Matrix3x3::Scale(scale);
+        return rotate * Matrix3x3::FromScale(scale);
     }
 
     Matrix3x3 Matrix3x3::FromQuat(const Quaternion &orientation) {
         return Matrix3x3(orientation);
     }
 
+    Matrix3x3 Matrix3x3::ScaleBy(const Vector3 &rhs) {
+        return *this * FromScale(rhs);
+    }
+
+    Vector3 Matrix3x3::GetScale() const {
+        return Vector3(GetColumn(0).Length(), GetColumn(1).Length(), GetColumn(2).Length());
+    }
+
+    Vector3 Matrix3x3::operator[](int row) const {
+        return Vector3{elems[row][0], elems[row][1], elems[row][2]};
+    }
+
+    Matrix3x3 Matrix3x3::FromScale(const Vector3 &scale) {
+        Matrix3x3 m;
+        m.At(0,0) = scale.x;
+        m.At(1,1) = scale.y;
+        m.At(2,2) = scale.z;
+        return m;
+    }
+
+    Matrix3x3 Matrix3x3::FromScale(float sx, float sy, float sz) {
+        Matrix3x3 m;
+        m.At(0,0) = sx;
+        m.At(1,1) = sy;
+        m.At(2,2) = sz;
+        return m;
+    }
+
+    void Matrix3x3::Orthonormalize(int c0, int c1, int c2) {
+        Vector3 v0 = GetColumn(c0);
+        Vector3 v1 = GetColumn(c1);
+        Vector3 v2 = GetColumn(c2);
+        Vector3::Orthonormalize(v0, v1, v2);
+        SetColumn(c0, v0);
+        SetColumn(c1, v1);
+        SetColumn(c2, v2);
+    }
+
 }