Implement by-Reference operators

CMakeLists.txt

@@ -57,7 +57,11 @@ add_library(J3ML SHARED ${J3ML_SRC}
         include/J3ML/Geometry/AABB2D.h
         src/J3ML/Geometry/Polygon.cpp
         include/J3ML/Geometry/Polyhedron.h
-        src/J3ML/Geometry/Polyhedron.cpp)
+        src/J3ML/Geometry/Polyhedron.cpp
+        include/J3ML/Algorithm/RNG.h
+        src/J3ML/Algorithm/RNG.cpp
+        include/J3ML/Algorithm/Spring.h
+        include/J3ML/Algorithm/DifferentialSolvers.h)
 set_target_properties(J3ML PROPERTIES LINKER_LANGUAGE CXX)
 
 install(TARGETS ${PROJECT_NAME} DESTINATION lib/${PROJECT_NAME})

include/J3ML/Algorithm/DifferentialSolvers.h

@@ -0,0 +1,36 @@
+//
+// Created by dawsh on 2/8/24.
+//
+
+namespace J3ML::Algorithm
+{
+    /// Implementations for a variety of Differential Equation Solving algorithms
+    namespace Solvers
+    {
+
+        // Consider a differential equation
+        // dy/dx = (x + y + xy)
+        float eq(float x, float y)
+        {
+            return (x + y + x*y);
+        }
+
+        float euler(float x0, float y, float h, float x)
+        {
+            float temp = -0.f;
+            // Iterating till the point at which we need approximation
+            while (x0 < x) {
+                temp = y;
+                y = y + h * eq(x0, y);
+                x0 = x0 + h;
+            }
+            return y;
+        }
+
+        class EulerMethodSolver {};
+        class SemiImplicitEulerMethodSolver {};
+        class GaussSeidelMethodSolver {};
+        class GradientDescentSolver {};
+        class VerletIntegrationSolver {};
+    }
+}

include/J3ML/Algorithm/RNG.h

@@ -0,0 +1,99 @@
+#pragma once
+
+
+#include "J3ML/J3ML.h"
+
+namespace J3ML::Algorithm
+{
+/** @brief A linear congruential random number generator.
+
+	Uses D.H. Lehmer's Linear Congruential Method (1949) for generating random numbers.
+	Supports both Multiplicative Congruential Method (increment==0) and
+	Mixed Congruential Method (increment!=0)
+	It is perhaps the simplest and fastest method to generate pseudo-random numbers on
+	a computer. Per default uses the values for Minimal Standard LCG.
+	http://en.wikipedia.org/wiki/Linear_congruential_generator
+	http://www.math.rutgers.edu/~greenfie/currentcourses/sem090/pdfstuff/jp.pdf
+
+	Pros:
+	<ul>
+	    <li> Easy to implement.
+	    <li> Fast.
+	</ul>
+
+	Cons:
+	<ul>
+	    <li> NOT safe for cryptography because of the easily calculatable sequential
+	        correlation between successive calls. A case study:
+	        http://www.cigital.com/papers/download/developer_gambling.php
+
+	    <li> Tends to have less random low-order bits (compared to the high-order bits)
+	         Thus, NEVER do something like this:
+
+	           u32 numBetween1And10 = 1 + LCGRand.Int() % 10;
+
+	         Instead, take into account EVERY bit of the generated number, like this:
+
+	           u32 numBetween1And10 = 1 + (int)(10.0 * (double)LCGRand.Int()
+	                                                      /(LCGRand.Max()+1.0));
+	         or simply
+
+	           u32 numBetween1And10 = LCGRand.Float(1.f, 10.f);
+	</ul> */
+
+
+    class RNG {
+    public:
+        /// Initializes the generator from the current system clock.
+        RNG();
+        RNG(u32 seed, u32 multiplier = 69621,
+            u32 increment = 0, u32 modulus = 0x7FFFFFFF) // 2^31 - 1
+        {
+            Seed(seed, multiplier, increment, modulus);
+        }
+        /// Reinitializes the generator to the new settings.
+        void Seed(u32 seed, u32 multiplier, u32 increment, u32 modulus = 0x7FFFFFFF);
+        /// Returns a random integer picked uniformly in the range [0, MaxInt()]
+        u32 Int();
+        /// Returns the biggest number the generator can yield. [modulus - 1]
+        u32 MaxInt() const { return modulus - 1;}
+        /// Returns a random integer picked uniformly in the range [0, 2^32-1].
+        /// @note The configurable modulus and increment are not used by this function, but are always increment == 0, modulus=2^32
+        u32 IntFast();
+        /// Returns a random integer picked uniformly in the range [a, b]
+        /// @param a Lower bound, inclusive.
+        /// @param b Upper bound, inclusive.
+        /// @return A random integer picked uniformly in the range [a, b]
+        int Int(int a, int b);
+
+        /// Returns a random float picked uniformly in the range [0, 1].
+        float Float();
+
+        /// Returns a random float picked uniformly in the range [0, 1].
+        /// @note this is much slower than Float()! Prefer that function if possible.
+        float Float01Incl();
+
+        /// Returns a random float picked uniformly in the range ]-1, 1[.
+        /// @note This function has one more bit of randomness compared to Float(), but has a theoretical bias
+        /// towards 0.0, since floating point has two representations for 0 (+0, and -0).
+        float FloatNeg1_1();
+
+        /// Returns a random float picked uniformly in the range [a, b[.
+        /// @param a Lower bound, inclusive.
+        /// @param b Upper bound, exclusive.
+        /// @return A random float picked uniformly in the range [a, b[
+        /// @note This function is slower than RNG::FloatIncl(). If you don't care about the open/closed interval, prefer that function.
+        float Float(float a, float b);
+
+        /// Returns a random float picked uniformly in the range [a, b].
+        /// @param a Lower bound, inclusive.
+        /// @param b Upper bound, inclusive.
+        /// @return A random float picked uniformly in the range [a, b]
+        float FloatIncl(float a, float b);
+
+        u32 multiplier;
+        u32 increment;
+        u32 modulus;
+        u32 lastNumber;
+    };
+}

include/J3ML/Algorithm/Spring.h

@@ -0,0 +1,21 @@
+//
+// Created by dawsh on 2/8/24.
+//
+
+namespace J3ML::Algorithm
+{
+    // Numerical model of a "Spring" object
+    // Simulates any oscillating system i.e. a mass suspended from a spring.
+    class Spring
+    {
+        float Dampening;
+        float Stiffness;
+        float Goal;
+        float RestLength = 1.f;
+
+        bool Overdamped() const;
+        bool Undamped() const;
+        bool Underdamped() const;
+        bool CriticallyDamped() const;
+    };
+}

include/J3ML/Geometry.h

@@ -3,9 +3,9 @@
 
 #pragma once
 
-namespace Geometry {
-    using Vector2 = LinearAlgebra::Vector2;
-    using Vector3 = LinearAlgebra::Vector3;
+namespace J3ML::Geometry {
+    using Vector2 = J3ML::LinearAlgebra::Vector2;
+    using Vector3 = J3ML::LinearAlgebra::Vector3;
 
     class LineSegment2D
     {

include/J3ML/Geometry/AABB.h

@@ -22,9 +22,8 @@
 
 
 
-namespace Geometry
+namespace J3ML::Geometry
 {
-
     using namespace LinearAlgebra;
     // A 3D axis-aligned bounding box
     // This data structure can be used to represent coarse bounds of objects, in situations where detailed triangle-level
@@ -35,36 +34,74 @@ namespace Geometry
     // be arbitrarily oriented in the space with respect to each other.
     // If you need to represent a box in 3D space with arbitrary orientation, see the class OBB. */
 
-    class AABB
-    {
-        static AABB FromCenterAndSize(const Vector3 FromSize);
-        float MinX();
-        // Returns the smallest sphere that contains this AABB.
-        // This function computes the minimal volume sphere that contains all the points inside this AABB
+    class AABB {
+    public:
+        Vector3 minPoint;
+        Vector3 maxPoint;
+
+        static int NumFaces() { return 6; }
+
+        static int NumEdges() { return 12; }
+
+        static int NumVertices() { return 8; }
+
+        static AABB FromCenterAndSize(const Vector3 &center, const Vector3 &size);
+
+        float MinX() const;
+
+        float MinY() const;
+
+        float MinZ() const;
+
+        float MaxX() const;
+
+        float MaxY() const;
+
+        float MaxZ() const;
+
+        /// Returns the smallest sphere that contains this AABB.
+        /// This function computes the minimal volume sphere that contains all the points inside this AABB
         Sphere MinimalEnclosingSphere() const;
-        // Returns the largest sphere that can fit inside this AABB
-        // This function computes the largest sphere that can fit inside this AABB.
+
+        Vector3 HalfSize() const;
+
+        /// Returns the largest sphere that can fit inside this AABB
+        /// This function computes the largest sphere that can fit inside this AABB.
         Sphere MaximalContainedSphere() const;
-        Vector3 GetCentroid() const;
+
+        bool IsFinite() const;
+
+        Vector3 Centroid() const;
+
+        Vector3 Size() const;
+
         // Quickly returns an arbitrary point inside this AABB
         Vector3 AnyPointFast() const;
 
         Vector3 PointInside(float x, float y, float z) const;
+
         // Returns an edge of this AABB
         LineSegment Edge(int edgeIndex) const;
-        Vector3 CornerPoint(int cornerIndex);
-        Vector3 ExtremePoint(const Vector3& direction) const;
-        Vector3 ExtremePoint(const Vector3& direction, float projectionDistance);
+
+        Vector3 CornerPoint(int cornerIndex) const;
+
+        Vector3 ExtremePoint(const Vector3 &direction) const;
+
+        Vector3 ExtremePoint(const Vector3 &direction, float &projectionDistance);
+
         Vector3 PointOnEdge(int edgeIndex, float u) const;
+
         Vector3 FaceCenterPoint(int faceIndex) const;
+
         Vector3 FacePoint(int faceIndex, float u, float v) const;
+
         Vector3 FaceNormal(int faceIndex) const;
-        Plane FacePlane(int faceIndex);
-        static AABB MinimalEnclosingAABB(const Vector3* pointArray, int numPoints);
-        Vector3 GetSize();
-        Vector3 GetVolume();
-        float GetVolumeCubed();
-        float GetSurfaceArea();
+
+        Plane FacePlane(int faceIndex) const;
+
+        static AABB MinimalEnclosingAABB(const Vector3 *pointArray, int numPoints);
+        float GetVolume() const;
+        float GetSurfaceArea() const;
         Vector3 GetRandomPointInside();
         Vector3 GetRandomPointOnSurface();
         Vector3 GetRandomPointOnEdge();
@@ -96,5 +133,26 @@ namespace Geometry
         TriangleMesh Triangulate(int numFacesX, int numFacesY, int numFacesZ, bool ccwIsFrontFacing) const;
         AABB Intersection(const AABB& rhs) const;
         bool IntersectLineAABB(const Vector3& linePos, const Vector3& lineDir, float tNear, float tFar) const;
+
+
+        void SetFrom(const Vector3 *pVector3, int i);
+
+        void SetFromCenterAndSize(const Vector3 &center, const Vector3 &size);
+
+        void SetFrom(const OBB &obb);
+
+        void SetFrom(const Sphere &s);
+
+        Vector3 GetRandomPointInside() const;
+
+        void SetNegativeInfinity();
+
+        void Enclose(const Vector3 &point);
+
+        void Enclose(const Vector3 &aabbMinPt, const Vector3 &aabbMaxPt);
+
+        void Enclose(const LineSegment &lineSegment);
+
+        void Enclose(const OBB &obb);
     };
 }

include/J3ML/Geometry/AABB2D.h

@@ -2,7 +2,7 @@
 
 #include <J3ML/LinearAlgebra/Vector2.h>
 
-namespace Geometry
+namespace J3ML::Geometry
 {
     using LinearAlgebra::Vector2;
     // CaveGame AABB

include/J3ML/Geometry/Capsule.h

@@ -3,7 +3,7 @@
 #include "LineSegment.h"
 #include <J3ML/LinearAlgebra/Vector3.h>
 
-namespace Geometry
+namespace J3ML::Geometry
 {
     using namespace LinearAlgebra;
     class Capsule
@@ -13,10 +13,10 @@ namespace Geometry
         // Specifies the radius of this capsule
         float r;
 
-        Capsule() {}
+        Capsule();
         Capsule(const LineSegment& endPoints, float radius);
         Capsule(const Vector3& bottomPt, const Vector3& topPt, float radius);
-        bool IsDegenerate()const;
+        bool IsDegenerate() const;
         float Height() const;
         float Diameter() const;
         Vector3 Bottom() const;

include/J3ML/Geometry/Frustum.h

@@ -6,9 +6,11 @@
 #include "Plane.h"
 #include <J3ML/LinearAlgebra/CoordinateFrame.h>
 
-namespace Geometry
+namespace J3ML::Geometry
 {
 
+    using J3ML::LinearAlgebra::CoordinateFrame;
+
     enum class FrustumType
     {
         Invalid,

include/J3ML/Geometry/LineSegment.h

@@ -2,11 +2,14 @@
 
 #include <J3ML/LinearAlgebra/Vector3.h>
 
-namespace Geometry
+namespace J3ML::Geometry
 {
     using LinearAlgebra::Vector3;
     class LineSegment
     {
+    public:
+        LineSegment();
+        LineSegment(const Vector3& a, const Vector3& b);
         Vector3 A;
         Vector3 B;
     };

include/J3ML/Geometry/OBB.h

@@ -5,7 +5,7 @@
 #include <J3ML/Geometry/LineSegment.h>
 #include <J3ML/Geometry/Polyhedron.h>
 
-namespace Geometry {
+namespace J3ML::Geometry {
     class OBB
     {
     public:

include/J3ML/Geometry/Plane.h

@@ -1,13 +1,18 @@
 #pragma once
 #include <J3ML/LinearAlgebra/Vector3.h>
 
-using namespace LinearAlgebra;
 
-class Plane
+
+namespace J3ML::Geometry
 {
-public:
-    Vector3 Position;
-    Vector3 Normal;
-    float distance = 0.f;
+    using J3ML::LinearAlgebra::Vector3;
 
-};
+    class Plane
+    {
+    public:
+        Vector3 Position;
+        Vector3 Normal;
+        float distance = 0.f;
+
+    };
+}

include/J3ML/Geometry/Polygon.h

@@ -1,6 +1,6 @@
 #pragma once
 
-namespace Geometry {
+namespace J3ML::Geometry {
     class Polygon {
 
     };

include/J3ML/Geometry/Polyhedron.h

@@ -1,6 +1,6 @@
 #pragma once
 
-namespace Geometry
+namespace J3ML::Geometry
 {
     class Polyhedron {
 

include/J3ML/Geometry/QuadTree.h

@@ -5,7 +5,7 @@
 #include <J3ML/LinearAlgebra/Vector2.h>
 #include "AABB2D.h"
 
-namespace Geometry {
+namespace J3ML::Geometry {
 
 
     using LinearAlgebra::Vector2;

include/J3ML/Geometry/Ray.h

@@ -6,7 +6,7 @@
 
 #include <J3ML/LinearAlgebra/Vector3.h>
 
-namespace Geometry
+namespace J3ML::Geometry
 {
     using LinearAlgebra::Vector3;
     class Ray

include/J3ML/Geometry/Sphere.h

@@ -1,9 +1,15 @@
 #pragma once
 
-namespace Geometry
+#include "J3ML/Geometry.h"
+
+namespace J3ML::Geometry
 {
     class Sphere
     {
+    public:
+        Sphere(const Vector3& pos, float radius)
+        {
 
+        }
     };
 }

include/J3ML/Geometry/Triangle.h

@@ -1,6 +1,6 @@
 #pragma once
 
-namespace Geometry
+namespace J3ML::Geometry
 {
     class Triangle
     {

include/J3ML/Geometry/Triangle2D.h

@@ -1,8 +1,10 @@
-//
-// Created by dawsh on 1/25/24.
-//
+#pragma once
 
-#ifndef J3ML_TRIANGLE2D_H
-#define J3ML_TRIANGLE2D_H
 
-#endif //J3ML_TRIANGLE2D_H
+namespace J3ML::Geometry
+{
+    class Shape2D {};
+    class Triangle2D {
+    public:
+    };
+}

include/J3ML/Geometry/TriangleMesh.h

@@ -1,6 +1,6 @@
 #pragma once
 
-namespace Geometry
+namespace J3ML::Geometry
 {
     class TriangleMesh
     {

include/J3ML/LinearAlgebra.h

@@ -6,7 +6,7 @@
 #include <functional>
 
 
-namespace Math
+namespace J3ML::Math
 {
     const float Pi = M_PI;
     inline float Radians(float degrees) { return degrees * (Pi/180.f); }
@@ -29,7 +29,7 @@ namespace Math
 
 
 // Dawsh Linear Algebra Library - Everything you need for 3D math
-namespace LinearAlgebra {
+namespace J3ML::LinearAlgebra {
     class Vector2; // A type representing a position in a 2-dimensional coordinate space.
     class Vector3; // A type representing a position in a 3-dimensional coordinate space.
     class Vector4; // A type representing a position in a 4-dimensional coordinate space.

include/J3ML/LinearAlgebra/Angle2D.h

@@ -2,7 +2,7 @@
 
 #include <J3ML/LinearAlgebra.h>
 
-namespace LinearAlgebra {
+namespace J3ML::LinearAlgebra {
     class Angle2D {
     public:
         float x;

include/J3ML/LinearAlgebra/AxisAngle.h

@@ -3,7 +3,7 @@
 #include <J3ML/LinearAlgebra.h>
 #include <J3ML/LinearAlgebra/Vector3.h>
 
-namespace LinearAlgebra
+namespace J3ML::LinearAlgebra
 {
 
     /// Transitional datatype, not useful for internal representation of rotation

include/J3ML/LinearAlgebra/CoordinateFrame.h

@@ -3,7 +3,7 @@
 #include <J3ML/LinearAlgebra.h>
 #include <J3ML/LinearAlgebra/Vector3.h>
 
-namespace LinearAlgebra
+namespace J3ML::LinearAlgebra
 {
     /// The CFrame is fundamentally 4 vectors (position, forward, right, up vector)
     class CoordinateFrame

include/J3ML/LinearAlgebra/EulerAngle.h

@@ -2,7 +2,7 @@
 #include <J3ML/LinearAlgebra.h>
 #include <J3ML/LinearAlgebra/Vector3.h>
 
-namespace LinearAlgebra {
+namespace J3ML::LinearAlgebra {
 
 // Essential Reading:
 // http://www.essentialmath.com/GDC2012/GDC2012_JMV_Rotations.pdf

include/J3ML/LinearAlgebra/Matrix2x2.h

@@ -3,7 +3,7 @@
 #include <J3ML/LinearAlgebra.h>
 #include <J3ML/LinearAlgebra/Vector2.h>
 
-namespace LinearAlgebra {
+namespace J3ML::LinearAlgebra {
     class Matrix2x2 {
     public:
         enum { Rows = 3 };

include/J3ML/LinearAlgebra/Matrix3x3.h

@@ -5,7 +5,7 @@
 #include <J3ML/LinearAlgebra/Vector3.h>
 #include <J3ML/LinearAlgebra/Quaternion.h>
 
-namespace LinearAlgebra {
+namespace J3ML::LinearAlgebra {
     /// A 3-by-3 matrix for linear transformations of 3D geometry.
     /* This can represent any kind of linear transformations of 3D geometry, which include
      * rotation, scale, shear, mirroring, and orthographic projection.
@@ -44,6 +44,7 @@ namespace LinearAlgebra {
         Vector3 GetRow(int index) const;
         Vector3 GetColumn(int index) const;
 
+        float &At(int row, int col);
         float At(int x, int y) const;
 
         void SetRotatePart(const Vector3& a, float angle);
@@ -60,23 +61,11 @@ 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);
 
-        static Matrix3x3 FromQuat(const Quaternion& orientation)
-        {
-            return Matrix3x3(orientation);
-        }
+        static Matrix3x3 FromQuat(const Quaternion& orientation);
 
         Quaternion ToQuat() const;
 
@@ -86,20 +75,14 @@ namespace LinearAlgebra {
         // Transforming a vector v using this matrix computes the vector
         // v' == M * v == R*S*v == (R * (S * v)) which means the scale operation
         // is applied to the vector first, followed by rotation, and finally translation
-        static Matrix3x3 FromRS(const Quaternion& rotate, const Vector3& scale)
-        {
-            return Matrix3x3(rotate) * Matrix3x3::Scale(scale);
-        }
-        static Matrix3x3 FromRS(const Matrix3x3 &rotate, const Vector3& scale)
-        {
-            return rotate * Matrix3x3::Scale(scale);
-        }
+        static Matrix3x3 FromRS(const Quaternion& rotate, const Vector3& scale);
+        static Matrix3x3 FromRS(const Matrix3x3 &rotate, const Vector3& scale);
 
 
         /// 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;
@@ -133,6 +116,11 @@ namespace LinearAlgebra {
         Vector3 Transform(const Vector3& rhs) const;
 
 
+        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;
 

include/J3ML/LinearAlgebra/Matrix4x4.h

@@ -3,7 +3,7 @@
 #include <J3ML/LinearAlgebra.h>
 #include <J3ML/LinearAlgebra/Quaternion.h>
 
-namespace LinearAlgebra {
+namespace J3ML::LinearAlgebra {
 
     /// A 4-by-4 matrix for affine transformations and perspective projections of 3D geometry.
     /* This matrix can represent the most generic form of transformations for 3D objects,
@@ -12,7 +12,7 @@ namespace LinearAlgebra {
      * The elements of this matrix are
      *  m_00, m_01, m_02, m_03
      *  m_10, m_11, m_12, m_13
-     *  m_20, m_21, m_22, am_23,
+     *  m_20, m_21, m_22, m_23,
      *  m_30, m_31, m_32, m_33
      *
      *  The element m_yx is the value on the row y and column x.
@@ -20,6 +20,7 @@ namespace LinearAlgebra {
      */
     class Matrix4x4 {
     public:
+        // TODO: Implement assertions to ensure matrix bounds are not violated!
         enum { Rows = 4 };
         enum { Cols = 4 };
 
@@ -43,9 +44,9 @@ namespace LinearAlgebra {
         /// The elements are specified in row-major format, i.e. the first row first followed by the second and third row.
         /// E.g. The element _10 denotes the scalar at second (index 1) row, first (index 0) column.
         Matrix4x4(float m00, float m01, float m02, float m03,
-            float m10, float m11, float m12, float m13,
-            float m20, float m21, float m22, float m23,
-            float m30, float m31, float m32, float m33);
+                  float m10, float m11, float m12, float m13,
+                  float m20, float m21, float m22, float m23,
+                  float m30, float m31, float m32, float m33);
         /// Constructs the matrix by explicitly specifying the four column vectors.
         /** @param col0 The first column. If this matrix represents a change-of-basis transformation, this parameter is the world-space
             direction of the local X axis.
@@ -57,37 +58,97 @@ namespace LinearAlgebra {
             position of the local space pivot. */
         Matrix4x4(const Vector4& r1, const Vector4& r2, const Vector4& r3, const Vector4& r4);
 
-
         explicit Matrix4x4(const Quaternion& orientation);
 
         /// Constructs this float4x4 from the given quaternion and translation.
         /// Logically, the translation occurs after the rotation has been performed.
         Matrix4x4(const Quaternion& orientation, const Vector3 &translation);
 
+        /// Creates a LookAt matrix from a look-at direction vector.
+        /** A LookAt matrix is a rotation matrix that orients an object to face towards a specified target direction.
+            @param localForward Specifies the forward direction in the local space of the object. This is the direction
+                the model is facing at in its own local/object space, often +X (1,0,0), +Y (0,1,0) or +Z (0,0,1). The
+                vector to pass in here depends on the conventions you or your modeling software is using, and it is best
+                pick one convention for all your objects, and be consistent.
+                This input parameter must be a normalized vector.
+            @param targetDirection Specifies the desired world space direction the object should look at. This function
+                will compute a rotation matrix which will rotate the localForward vector to orient towards this targetDirection
+                vector. This input parameter must be a normalized vector.
+            @param localUp Specifies the up direction in the local space of the object. This is the up direction the model
+                was authored in, often +Y (0,1,0) or +Z (0,0,1). The vector to pass in here depends on the conventions you
+                or your modeling software is using, and it is best to pick one convention for all your objects, and be
+                consistent. This input parameter must be a normalized vector. This vector must be perpendicular to the
+                vector localForward, i.e. localForward.Dot(localUp) == 0.
+            @param worldUp Specifies the global up direction of the scene in world space. Simply rotating one vector to
+                coincide with another (localForward->targetDirection) would cause the up direction of the resulting
+                orientation to drift (e.g. the model could be looking at its target its head slanted sideways). To keep
+                the up direction straight, this function orients the localUp direction of the model to point towards the
+                specified worldUp direction (as closely as possible). The worldUp and targetDirection vectors cannot be
+                collinear, but they do not need to be perpendicular either.
+            @return A matrix that maps the given local space forward direction vector to point towards the given target
+                direction, and the given local up direction towards the given target world up direction. The returned
+                matrix M is orthonormal with a determinant of +1. For the matrix M it holds that
+                M * localForward = targetDirection, and M * localUp lies in the plane spanned by the vectors targetDirection
+                and worldUp.
+            @note The position of (the translation performed by) the resulting matrix will be set to (0,0,0), i.e. the object
+                will be placed to origin. Call SetTranslatePart() on the resulting matrix to set the position of the model.
+            @see RotateFromTo(). */
+        static Matrix4x4 LookAt(const Vector3& localFwd, const Vector3& targetDir, const Vector3& localUp, const Vector3& worldUp);
+
+        /// Returns the translation part.
+        /** The translation part is stored in the fourth column of this matrix.
+            This is equivalent to decomposing this matrix in the form M = T * M', i.e. this translation is applied last,
+            after applying rotation and scale. If this matrix represents a local->world space transformation for an object,
+            then this gives the world space position of the object.
+            @note This function assumes that this matrix does not contain projection (the fourth row of this matrix is [0 0 0 1]). */
         Vector3 GetTranslatePart() const;
-        Matrix3x3 GetRotatePart() const
-        {
-            return Matrix3x3 {
-                At(0, 0), At(0, 1), At(0, 2),
-                At(1, 0), At(1, 1), At(1, 2),
-                At(2, 0), At(2, 1), At(2, 2)
-            };
-        }
+        /// Returns the top-left 3x3 part of this matrix. This stores the rotation part of this matrix (if this matrix represents a rotation).
+        Matrix3x3 GetRotatePart() const;
         void SetTranslatePart(float translateX, float translateY, float translateZ);
         void SetTranslatePart(const Vector3& offset);
         void SetRotatePart(const Quaternion& q);
-        void SetRotatePart(const Matrix3x3& r);
-
+        void Set3x3Part(const Matrix3x3& r);
 
         void SetRow(int row, const Vector3& rowVector, float m_r3);
         void SetRow(int row, const Vector4& rowVector);
         void SetRow(int row, float m_r0, float m_r1, float m_r2, float m_r3);
 
-
         Vector4 GetRow(int index) const;
         Vector4 GetColumn(int index) const;
+        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;
 
+        template <typename T>
+        void Swap(T &a, T &b)
+        {
+            T temp = std::move(a);
+            a = std::move(b);
+            b = std::move(temp);
+        }
+
+
+        void SwapColumns(int col1, int col2);
+
+        /// Swaps two rows.
+        void SwapRows(int row1, int row2);
+        /// Swapsthe xyz-parts of two rows element-by-element
+        void SwapRows3(int row1, int row2);
+
+        void ScaleRow(int row, float scalar);
+        void ScaleRow3(int row, float scalar);
+        void ScaleColumn(int col, float scalar);
+        void ScaleColumn3(int col, float scalar);
+        /// Algorithm from Eric Lengyel's Mathematics for 3D Game Programming & Computer Graphics, 2nd Ed.
+        void Pivot();
+
         /// Tests if this matrix does not contain any NaNs or infs.
         /** @return Returns true if the entries of this float4x4 are all finite, and do not contain NaN or infs. */
         bool IsFinite() const;
@@ -97,23 +158,52 @@ namespace LinearAlgebra {
         bool IsInvertible(float epsilon = 1e-3f) const;
 
         Vector4 Diagonal() const;
-        Vector4 WorldX() const;
-        Vector4 WorldY() const;
-        Vector4 WorldZ() const;
+        Vector3 Diagonal3() const;
+        /// Returns the local +X axis in world space.
+        /// This is the same as transforming the vector (1,0,0) by this matrix.
+        Vector3 WorldX() const;
+        /// Returns the local +Y axis in world space.
+        /// This is the same as transforming the vector (0,1,0) by this matrix.
+        Vector3 WorldY() const;
+        /// Returns the local +Z axis in world space.
+        /// This is the same as transforming the vector (0,0,1) by this matrix.
+        Vector3 WorldZ() const;
 
+        /// Accesses this structure as a float array.
+        /// @return A pointer to the upper-left element. The data is contiguous in memory.
+        /// ptr[0] gives the element [0][0], ptr[1] is [0][1], ptr[2] is [0][2].
+        /// ptr[4] == [1][0], ptr[5] == [1][1], ..., and finally, ptr[15] == [3][3].
+        float *ptr() { return &elems[0][0]; }
+        const float *ptr() const { return &elems[0][0]; }
+
+        float Determinant3x3() const;
         /// Computes the determinant of this matrix.
         // If the determinant is nonzero, this matrix is invertible.
         float Determinant() const;
 
+        #define SKIPNUM(val, skip) (val >= skip ? (val+1) : val)
+
+        float Minor(int i, int j) const;
+
         Matrix4x4 Inverse() const;
 
         Matrix4x4 Transpose() const;
 
+        Vector2 Transform(float tx, float ty) const;
         Vector2 Transform(const Vector2& rhs) const;
+
+
+        Vector3 Transform(float tx, float ty, float tz) const;
         Vector3 Transform(const Vector3& rhs) const;
+
+        Vector4 Transform(float tx, float ty, float tz, float tw) const;
         Vector4 Transform(const Vector4& rhs) const;
 
 
+        Matrix4x4 Translate(const Vector3& rhs) const;
+        static Matrix4x4 FromTranslation(const Vector3& rhs);
+
+
         static Matrix4x4 D3DOrthoProjLH(float nearPlane, float farPlane, float hViewportSize, float vViewportSize);
         static Matrix4x4 D3DOrthoProjRH(float nearPlane, float farPlane, float hViewportSize, float vViewportSize);
         static Matrix4x4 D3DPerspProjLH(float nearPlane, float farPlane, float hViewportSize, float vViewportSize);
@@ -124,12 +214,6 @@ namespace LinearAlgebra {
         static Matrix4x4 OpenGLPerspProjLH(float nearPlane, float farPlane, float hViewportSize, float vViewportSize);
         static Matrix4x4 OpenGLPerspProjRH(float nearPlane, float farPlane, float hViewportSize, float vViewportSize);
 
-        Vector3 GetTranslationComponent() const;
-        Matrix3x3 GetRotationComponent() const;
-
-        Vector4 GetRow() const;
-        Vector4 GetColumn() const;
-
         Vector4 operator[](int row);
 
         Matrix4x4 operator-() const;
@@ -139,9 +223,11 @@ namespace LinearAlgebra {
         Matrix4x4 operator *(float scalar) const;
         Matrix4x4 operator /(float scalar) const;
 
-        Vector2 operator * (const Vector2& rhs) const { return this->Transform(rhs);}
-        Vector3 operator * (const Vector3& rhs) const { return this->Transform(rhs);}
-        Vector4 operator * (const Vector4& rhs) const { return this->Transform(rhs);}
+
+
+        Vector2 operator * (const Vector2& rhs) const;
+        Vector3 operator * (const Vector3& rhs) const;
+        Vector4 operator * (const Vector4& rhs) const;
 
         Matrix4x4 operator * (const Matrix3x3 &rhs) const;
 
@@ -149,23 +235,13 @@ namespace LinearAlgebra {
 
         Matrix4x4 operator * (const Matrix4x4& rhs) const;
 
-        Matrix4x4 &operator = (const Matrix3x3& rhs)
-        {
-            SetRotatePart(rhs);
-            SetTranslatePart(0,0,0);
-            SetRow(3, 0, 0, 0, 1);
-            return *this;
-        }
-        Matrix4x4 &operator = (const Quaternion& rhs)
-        {
-            *this = rhs.ToMatrix4x4();
-            return *this;
-        }
+        Matrix4x4 &operator = (const Matrix3x3& rhs);
+        Matrix4x4 &operator = (const Quaternion& rhs);
         Matrix4x4 &operator = (const Matrix4x4& rhs) = default;
 
     protected:
         float elems[4][4];
 
-        void SetMatrixRotatePart(Matrix4x4 &m, const Quaternion &q);
+
     };
 }

include/J3ML/LinearAlgebra/Quaternion.h

@@ -6,7 +6,7 @@
 #include <J3ML/LinearAlgebra/AxisAngle.h>
 #include <J3ML/LinearAlgebra/Matrix3x3.h>
 
-namespace LinearAlgebra
+namespace J3ML::LinearAlgebra
 {
     class Quaternion : public Vector4 {
     public:

include/J3ML/LinearAlgebra/Transform2D.h

@@ -3,7 +3,7 @@
 #include <J3ML/LinearAlgebra.h>
 #include <J3ML/LinearAlgebra/Matrix3x3.h>
 
-namespace LinearAlgebra {
+namespace J3ML::LinearAlgebra {
     class Transform2D {
     protected:
         Matrix3x3 transformation;

include/J3ML/LinearAlgebra/Vector2.h

@@ -3,10 +3,9 @@
 #include <J3ML/LinearAlgebra.h>
 #include <cstddef>
 
-namespace LinearAlgebra {
+namespace J3ML::LinearAlgebra {
     using namespace J3ML;
 
-
     /// A 2D (x, y) ordered pair.
     class Vector2 {
     public:
@@ -14,6 +13,7 @@ namespace LinearAlgebra {
         Vector2();
         /// Constructs a new Vector2 with the value (X, Y)
         Vector2(float X, float Y);
+        Vector2(float* xyPtr);
         Vector2(const Vector2& rhs);   // Copy Constructor
         //Vector2(Vector2&&) = default;   // Move Constructor
 
@@ -29,13 +29,21 @@ namespace LinearAlgebra {
         void SetX(float newX);
         void SetY(float newY);
 
+        float* ptr()
+        {
+            return &x;
+        }
+
+        Vector2 Abs() const;
+
         bool IsWithinMarginOfError(const Vector2& rhs, float margin=0.001f) const;
 
         bool IsNormalized(float epsilonSq = 1e-5f) const;
         bool IsZero(float epsilonSq = 1e-6f) const;
         bool IsPerpendicular(const Vector2& other, float epsilonSq=1e-5f) const;
 
-        float operator[](std::size_t index);
+        float operator[](std::size_t index) const;
+        float &operator[](std::size_t index);
         bool operator == (const Vector2& rhs) const;
         bool operator != (const Vector2& rhs) const;
 
@@ -70,10 +78,6 @@ namespace LinearAlgebra {
         static float Magnitude(const Vector2& of);
 
 
-
-
-
-
         bool IsFinite() const;
         static bool IsFinite(const Vector2& v);
 
@@ -121,6 +125,10 @@ namespace LinearAlgebra {
         /// Multiplies this vector by a vector, element-wise
         /// @note Mathematically, the multiplication of two vectors is not defined in linear space structures,
         ///	 but this function is provided here for syntactical convenience.
+        Vector2 operator *(const Vector2& rhs) const
+        {
+
+        }
         Vector2 Mul(const Vector2& v) const;
 
         /// Divides this vector by a scalar.
@@ -147,4 +155,9 @@ namespace LinearAlgebra {
         float y = 0;
 
     };
+
+    static Vector2 operator*(float lhs, const Vector2 &rhs)
+    {
+        return rhs * lhs;
+    }
 }

include/J3ML/LinearAlgebra/Vector3.h

@@ -6,7 +6,7 @@
 #include <J3ML/LinearAlgebra/Angle2D.h>
 
 
-namespace LinearAlgebra {
+namespace J3ML::LinearAlgebra {
 
 // A 3D (x, y, z) ordered pair.
 class Vector3 {
@@ -29,6 +29,13 @@ public:
     static const Vector3 Forward;
     static const Vector3 Backward;
     static const Vector3 NaN;
+    static const Vector3 Infinity;
+    static const Vector3 NegativeInfinity;
+
+    float* ptr()
+    {
+        return &x;
+    }
 
     static void Orthonormalize(Vector3& a, Vector3& b)
     {
@@ -37,8 +44,10 @@ public:
         b = b.Normalize();
     }
 
+    Vector3 Abs() const;
 
-    //Returns the DirectionVector for a given angle.
+
+    /// Returns the DirectionVector for a given angle.
     static Vector3 Direction(const Vector3 &rhs) ;
 
 
@@ -75,9 +84,15 @@ public:
     bool IsPerpendicular(const Vector3& other, float epsilonSq=1e-5f) const;
 
     float operator[](std::size_t index) const;
+    float &operator[](std::size_t index);
     bool operator == (const Vector3& rhs) const;
     bool operator != (const Vector3& rhs) const;
 
+    bool IsFinite() const
+    {
+        return std::isfinite(x) && std::isfinite(y) && std::isfinite(z);
+    }
+
     Vector3 Min(const Vector3& min) const;
     static Vector3 Min(const Vector3& lhs, const Vector3& rhs);
 
@@ -87,7 +102,7 @@ public:
     Vector3 Clamp(const Vector3& min, const Vector3& max) const;
     static Vector3 Clamp(const Vector3& min, const Vector3& input, const Vector3& max);
 
-    // Returns the magnitude between the two vectors.
+    /// Returns the magnitude between the two vectors.
     float Distance(const Vector3& to) const;
     static float Distance(const Vector3& from, const Vector3& to);
 
@@ -97,33 +112,33 @@ public:
     float LengthSquared() const;
     static float LengthSquared(const Vector3& of);
 
-    // Returns the length of the vector, which is sqrt(x^2 + y^2 + z^2)
+    /// Returns the length of the vector, which is sqrt(x^2 + y^2 + z^2)
     float Magnitude() const;
     static float Magnitude(const Vector3& of);
 
-    // Returns a float value equal to the magnitudes of the two vectors multiplied together and then multiplied by the cosine of the angle between them.
-    // For normalized vectors, dot returns 1 if they point in exactly the same direction,
-    // -1 if they point in completely opposite directions, and 0 if the vectors are perpendicular.
+    /// Returns a float value equal to the magnitudes of the two vectors multiplied together and then multiplied by the cosine of the angle between them.
+    /// For normalized vectors, dot returns 1 if they point in exactly the same direction,
+    /// -1 if they point in completely opposite directions, and 0 if the vectors are perpendicular.
     float Dot(const Vector3& rhs) const;
     static float Dot(const Vector3& lhs, const Vector3& rhs);
 
-    // Projects one vector onto another and returns the result. (IDK)
+    /// Projects one vector onto another and returns the result. (IDK)
     Vector3 Project(const Vector3& rhs) const;
     static Vector3 Project(const Vector3& lhs, const Vector3& rhs);
 
-    // The cross product of two vectors results in a third vector which is perpendicular to the two input vectors.
-    // The result's magnitude is equal to the magnitudes of the two inputs multiplied together and then multiplied by the sine of the angle between the inputs.
+    /// The cross product of two vectors results in a third vector which is perpendicular to the two input vectors.
+    /// The result's magnitude is equal to the magnitudes of the two inputs multiplied together and then multiplied by the sine of the angle between the inputs.
     Vector3 Cross(const Vector3& rhs) const;
     static Vector3 Cross(const Vector3& lhs, const Vector3& rhs);
 
-    // Returns a copy of this vector, resized to have a magnitude of 1, while preserving "direction"
+    /// Returns a copy of this vector, resized to have a magnitude of 1, while preserving "direction"
     Vector3 Normalize() const;
     static Vector3 Normalize(const Vector3& targ);
 
-    // Linearly interpolates between two points.
-    // Interpolates between the points and b by the interpolant t.
-    // The parameter is (TODO: SHOULD BE!) clamped to the range[0, 1].
-    // This is most commonly used to find a point some fraction of the wy along a line between two endpoints (eg. to move an object gradually between those points).
+    /// Linearly interpolates between two points.
+    /// Interpolates between the points and b by the interpolant t.
+    /// The parameter is (TODO: SHOULD BE!) clamped to the range[0, 1].
+    /// This is most commonly used to find a point some fraction of the wy along a line between two endpoints (eg. to move an object gradually between those points).
     Vector3 Lerp(const Vector3& goal, float alpha) const;
     static Vector3 Lerp(const Vector3& lhs, const Vector3& rhs, float alpha);
 
@@ -136,28 +151,47 @@ public:
     Vector3 Add(const Vector3& rhs) const;
     static Vector3 Add(const Vector3& lhs, const Vector3& rhs);
 
-    // Subtracts two vectors
+    /// Subtracts two vectors
     Vector3 operator-(const Vector3& rhs) const;
     Vector3 Sub(const Vector3& rhs) const;
     static Vector3 Sub(const Vector3& lhs, const Vector3& rhs);
 
-    // Multiplies this vector by a scalar value
+    /// Multiplies this vector by a scalar value
     Vector3 operator*(float rhs) const;
     Vector3 Mul(float scalar) const;
     static Vector3 Mul(const Vector3& lhs, float rhs);
 
-    // Divides this vector by a scalar
+    /// Multiplies this vector by a vector, element-wise
+    /// @note Mathematically, the multiplication of two vectors is not defined in linear space structures,
+    ///	 but this function is provided here for syntactical convenience.
+    Vector3 Mul(const Vector3& rhs) const
+    {
+
+    }
+
+    /// Divides this vector by a scalar
     Vector3 operator/(float rhs) const;
     Vector3 Div(float scalar) const;
     static Vector3 Div(const Vector3& lhs, float rhs);
 
-    // Unary + operator
+
+    /// Divides this vector by a vector, element-wise
+    /// @note Mathematically, the multiplication of two vectors is not defined in linear space structures,
+    /// but this function is provided here for syntactical convenience
+    Vector2 Div(const Vector2& v) const;
+
+    /// Unary + operator
     Vector3 operator+() const; // TODO: Implement
-    // Unary - operator (Negation)
+    /// Unary - operator (Negation)
     Vector3 operator-() const;
 public:
      float x = 0;
      float y = 0;
      float z = 0;
 };
+
+    static Vector3 operator*(float lhs, const Vector3& rhs)
+    {
+        return rhs * lhs;
+    }
 }

include/J3ML/LinearAlgebra/Vector4.h

@@ -2,8 +2,7 @@
 
 #include <J3ML/LinearAlgebra.h>
 
-
-namespace LinearAlgebra {
+namespace J3ML::LinearAlgebra {
     class Vector4 {
     public:
         // Default Constructor
@@ -16,6 +15,11 @@ namespace LinearAlgebra {
         Vector4(Vector4&& move) = default;
         Vector4& operator=(const Vector4& rhs);
 
+        float* ptr()
+        {
+            return &x;
+        }
+
         float GetX() const;
         float GetY() const;
         float GetZ() const;
@@ -81,6 +85,8 @@ namespace LinearAlgebra {
 
         Vector4 operator+() const; // Unary + Operator
         Vector4 operator-() const; // Unary - Operator (Negation)
+
+
     public:
 #if MUTABLE
         float x;

src/J3ML/Algorithm/RNG.cpp

@@ -0,0 +1,154 @@
+#include <J3ML/Algorithm/RNG.h>
+#include <stdexcept>
+#include <cassert>
+
+
+namespace J3ML::Algorithm {
+    void RNG::Seed(J3ML::u32 seed, J3ML::u32 multiplier, J3ML::u32 increment, J3ML::u32 modulus) {
+        // If we have a pure multiplicative RNG, then can't have 0 starting seed, since that would generate a stream of all zeroes
+        if (seed == 0 && increment == 0) seed = 1;
+
+        if (increment == 0 && (multiplier % modulus == 0 || modulus % multiplier == 0 ))
+            throw std::runtime_error("Multiplier %u and modulus %u are not compatible since one is a multiple of the other and the increment == 0!");
+
+        // TODO: assert(multiplier != 0);
+        // TODO: assert(modulus > 1);
+
+        this->lastNumber = seed;
+        this->multiplier = multiplier;
+        this->increment = increment;
+        this->modulus = modulus;
+    }
+
+    u32 RNG::IntFast()
+    {
+        assert(increment == 0);
+        assert(multiplier % 2 == 1 && "Multiplier should be odd for RNG::IntFast(), since modulus==2^32 is even!");
+        // The configurable modulus and increment are not used by this function.
+        u32 mul = lastNumber * multiplier;
+        // Whenever we overflow, flip by one to avoud even multiplier always producing even results
+        // since modulus is even.
+        lastNumber = mul + (mul <= lastNumber?1:0);
+        // We don't use an adder in IntFast(), so must never degenerate to zero
+        assert(lastNumber != 0);
+        return lastNumber;
+    }
+
+    u32 RNG::Int()
+    {
+        assert(modulus != 0);
+        /// TODO: Convert to using Shrage's method for approximate factorization (Numerical Recipes in C)
+
+        // Currently we cast everything to 65-bit to avoid overflow, which is quite dumb.
+
+        // Creates the new random number
+        u64 newNum  = ((u64)lastNumber * (u64)multiplier + (u64)increment % (u64)modulus);
+
+        // TODO: use this on console platforms to rely on smaller sequences.
+        // u32 m = lastNumber * multiplier;
+        // u32 i = m + increment;
+        // u32 f = i & 0x7FFFFFFF;
+        // u32 m = (lastNumber * 214013 + 2531011) & 0x7FFFFFFF;
+        // unsigned __int64 newNum = (lastNumber * multiplier + increment) & 0x7FFFFFFF;
+        assert( ((u32)newNum!=0 || increment != 0) && "RNG degenerated to producing a stream of zeroes!");
+        lastNumber = (u32)newNum;
+        return lastNumber;
+    }
+
+    int RNG::Int(int a, int b) {
+        assert(a <= b && "Error in range!");
+
+        int num = a + (int)(Float() * (b-a+1));
+        // TODO: Some bug here - the result is not necessarily in the proper range.
+        if (num < a) num = a;
+        if (num > b) num = b;
+        return num;
+    }
+
+    /// Jesus-Fuck ~ Josh
+    /// As per C99, union-reinterpret should now be safe: http://stackoverflow.com/questions/8511676/portable-data-reinterpretation
+    union FloatIntReinterpret
+    {
+        float f;
+        u32 i;
+    };
+
+    template <typename To, typename From>
+    union ReinterpretOp {
+        To to;
+        From from;
+    };
+
+    template <typename To, typename From>
+    To ReinterpretAs(From input)
+    {
+        ReinterpretOp<To, From> fi {};
+        fi.to = input;
+        return fi.from;
+    }
+
+    float RNG::Float() {
+        u32 i = ((u32)Int() & 0x007FFFFF /* random mantissa */) | 0x3F800000 /* fixed exponent */;
+        auto f = ReinterpretAs<float, u32>(i); // f is now in range [1, 2[
+        f -= 1.f; // Map to range [0, 1[
+        assert(f >= 0.f);
+        assert(f < 1.f);
+        return f;
+    }
+
+
+    float RNG::Float01Incl() {
+        for (int i = 0; i < 100; ++i) {
+            u32 val = (u32)Int() & 0x00FFFFFF;
+            if (val > 0x800000)
+                continue;
+            else if (val = 0x800000)
+                return 1.f;
+            else {
+                val |= 0x3F800000;
+                float f = ReinterpretAs<float, u32>(val) - 1.f;
+                assert(f >= 0.f);
+                assert(f <= 1.f);
+                return f;
+            }
+        }
+        return Float();
+    }
+
+    float RNG::FloatNeg1_1() {
+        u32 i = (u32) Int();
+        u32 one = ((i & 0x00800000) << 8) /* random sign bit */ | 0x3F800000; /* fixed exponent */
+        i = one | (i & 0x007FFFFF); // Random mantissa
+        float f = ReinterpretAs<float, u32>(i); // f is now in range ]-2, -1[ union [1, 2].
+        float fone = ReinterpretAs<float, u32>(one); // +/- 1, of same sign as f.
+        f -= fone;
+        assert(f > -1.f);
+        assert(f < 1.f);
+        return f;
+    }
+
+    float RNG::Float(float a, float b) {
+        assert(a <= b && "");
+        if (a == b)
+            return a;
+
+        for (int i = 0; i < 10; ++i)
+        {
+            float f = a + Float() * (b - a);
+            if (f != b) {
+                assert(a <= f);
+                assert(f < b || a == b);
+                return f;
+            }
+        }
+        return a;
+    }
+
+    float RNG::FloatIncl(float a, float b) {
+        assert(a <= b && "RNG::Float(a, b): Error in range: b < a!");
+        float f = a + Float() * (b - a);
+        assert( a <= f);
+        assert(f <= b);
+        return f;
+    }
+}

src/J3ML/Geometry/AABB.cpp

@@ -1,5 +1,237 @@
 #include <J3ML/Geometry/AABB.h>
+#include <cassert>
 
-namespace Geometry {
+namespace J3ML::Geometry {
 
-}
+    AABB AABB::FromCenterAndSize(const J3ML::Geometry::Vector3 &center, const J3ML::Geometry::Vector3 &size) {
+        Vector3 halfSize =  size * 0.5f;
+        return {center - halfSize, center + halfSize};
+    }
+
+    float AABB::MinX() const { return minPoint.x; }
+
+    float AABB::MinY() const { return minPoint.y; }
+
+    float AABB::MinZ() const { return minPoint.z; }
+
+    float AABB::MaxX() const { return maxPoint.x; }
+
+    float AABB::MaxY() const { return maxPoint.y; }
+
+    float AABB::MaxZ() const { return maxPoint.z; }
+
+    Sphere AABB::MinimalEnclosingSphere() const {
+        return Sphere(Centroid(), Size().Length()*0.5f);
+    }
+
+    Vector3 AABB::HalfSize() const {
+        return this->Size()/2.f;
+    }
+
+    Sphere AABB::MaximalContainedSphere() const {
+        Vector3 halfSize = HalfSize();
+        return Sphere(Centroid(), std::min(halfSize.x, std::min(halfSize.y, halfSize.z)));
+    }
+
+    bool AABB::IsFinite() const {
+        return minPoint.IsFinite() && maxPoint.IsFinite();
+    }
+
+    Vector3 AABB::Centroid() const {
+        return (minPoint+maxPoint) * 0.5f;
+    }
+
+    Vector3 AABB::Size() const {
+        return this->maxPoint - this->minPoint;
+    }
+
+    Vector3 AABB::PointInside(float x, float y, float z) const {
+        Vector3 d = maxPoint - minPoint;
+        return minPoint + d.Mul({x, y, z});
+    }
+
+    LineSegment AABB::Edge(int edgeIndex) const {
+        switch(edgeIndex)
+        {
+            default:
+            case 0: return LineSegment(minPoint, {minPoint.x, minPoint.y, maxPoint.z});
+        }
+    }
+
+    Vector3 AABB::CornerPoint(int cornerIndex) const {
+        // TODO: assert(0 <= cornerIndex && cornerIndex <= 7)
+        switch(cornerIndex)
+        {
+            default:
+            case 0: return minPoint;
+            case 1: return {minPoint.x, minPoint.y, maxPoint.z};
+            case 2: return {minPoint.x, maxPoint.y, minPoint.z};
+            case 3: return {minPoint.x, maxPoint.y, maxPoint.z};
+            case 4: return {maxPoint.x, minPoint.y, minPoint.z};
+            case 5: return {maxPoint.x, minPoint.y, maxPoint.z};
+            case 6: return {maxPoint.x, maxPoint.y, minPoint.z};
+            case 7: return maxPoint;
+        }
+    }
+
+    Vector3 AABB::ExtremePoint(const Vector3 &direction) const {
+        return {direction.x >= 0.f ? maxPoint.x : minPoint.x,
+                direction.y >= 0.f ? maxPoint.y : minPoint.y,
+                direction.z >= 0.f ? maxPoint.z : minPoint.z};
+    }
+
+    Vector3 AABB::ExtremePoint(const Vector3 &direction, float &projectionDistance) {
+        auto extremePt = ExtremePoint(direction);
+        projectionDistance = extremePt.Dot(direction);
+        return extremePt;
+    }
+
+    Vector3 AABB::PointOnEdge(int edgeIndex, float u) const {
+        // TODO: assert(0 <= edgeIndex && edgeIndex <= 11);
+        // TODO: assert(0 <= u && u < 1.f);
+
+        auto d = maxPoint - minPoint;
+        switch(edgeIndex) {
+            default:
+            case 0: return {minPoint.x, minPoint.y, minPoint.z + u * d.z};
+            case 1: return {minPoint.x, maxPoint.y, minPoint.z + u * d.z};
+            case 2: return {maxPoint.x, minPoint.y, minPoint.z + u * d.z};
+            case 3: return {maxPoint.x, maxPoint.y, minPoint.z + u * d.z};
+
+            case 4: return {minPoint.x, minPoint.y + u * d.y, minPoint.z};
+            case 5: return {maxPoint.x, minPoint.y + u * d.y, minPoint.z};
+            case 6: return {minPoint.x, minPoint.y + u * d.y, maxPoint.z};
+            case 7: return {maxPoint.x, minPoint.y + u * d.y, maxPoint.z};
+
+            case 8: return {minPoint.x + u * d.x, minPoint.y, minPoint.z};
+            case 9: return {minPoint.x + u * d.x, minPoint.y, maxPoint.z};
+            case 10:return {minPoint.x + u * d.x, maxPoint.y, minPoint.z};
+            case 11:return {minPoint.x + u * d.x, maxPoint.y, maxPoint.z};
+        }
+    }
+
+    Vector3 AABB::FaceCenterPoint(int faceIndex) const {
+        // TODO: assert(0 <= faceIndex && faceIndex <= 5)
+        auto center = (minPoint + maxPoint) * 0.5f;
+        switch (faceIndex) {
+            default:
+            case 0: return {minPoint.x, center.y, center.z};
+            case 1: return {maxPoint.x, center.y, center.z};
+            case 2: return {center.x, minPoint.y, center.z};
+            case 3: return {center.x, maxPoint.y, center.z};
+            case 4: return {center.x, center.y, minPoint.z};
+            case 5: return {center.x, center.y, maxPoint.z};
+        }
+    }
+
+    Vector3 AABB::FacePoint(int faceIndex, float u, float v) const {
+        // TODO: assert(0 <= faceIndex && faceIndex <= 5);
+        // TODO: assert(0 <= u && u <= 1.f);
+        // TODO: assert(0 <= v && v <= 1.f);
+
+        auto d = maxPoint - minPoint;
+        switch(faceIndex)
+        {
+            default: // For release builds where assume() is disabled, return always the first option if out-of-bounds.
+            case 0: return {minPoint.x, minPoint.y + u * d.y, minPoint.z + v * d.z};
+            case 1: return {maxPoint.x, minPoint.y + u * d.y, minPoint.z + v * d.z};
+            case 2: return {minPoint.x + u * d.x, minPoint.y, minPoint.z + v * d.z};
+            case 3: return {minPoint.x + u * d.x, maxPoint.y, minPoint.z + v * d.z};
+            case 4: return {minPoint.x + u * d.x, minPoint.y + v * d.y, minPoint.z};
+            case 5: return {minPoint.x + u * d.x, minPoint.y + v * d.y, maxPoint.z};
+        }
+    }
+
+    Vector3 AABB::FaceNormal(int faceIndex) const {
+        // TODO: assert(0 <= faceIndex && faceIndex <= 5);
+        switch(faceIndex) {
+            default:
+            case 0: return {-1,  0,  0};
+            case 1: return { 1,  0,  0};
+            case 2: return { 0, -1,  0};
+            case 3: return { 0,  1,  0};
+            case 4: return { 0,  0, -1};
+            case 5: return { 0,  0,  1};
+        }
+    }
+
+    Plane AABB::FacePlane(int faceIndex) const {
+        // TODO: assert(0 <= faceIndex && faceIndex <= 5);
+        return Plane(FaceCenterPoint(faceIndex), FaceNormal(faceIndex));
+    }
+
+    AABB AABB::MinimalEnclosingAABB(const Vector3 *pointArray, int numPoints) {
+        AABB aabb;
+        aabb.SetFrom(pointArray, numPoints);
+        return aabb;
+    }
+
+    float AABB::GetVolume() const {
+        Vector3 sz = Size();
+        return sz.x * sz.y * sz.z;
+    }
+
+    float AABB::GetSurfaceArea() const {
+        Vector3 size = Size();
+        return 2.f * (size.x*size.y + size.x*size.z + size.y*size.z);
+    }
+
+    void AABB::SetFromCenterAndSize(const Vector3& center, const Vector3& size)
+    {
+
+    }
+
+
+    void AABB::SetFrom(const OBB& obb)
+    {
+
+    }
+
+    void AABB::SetFrom(const Sphere& s)
+    {
+
+    }
+
+    void AABB::SetFrom(const Vector3 *pointArray, int numPoints) {
+        assert(pointArray || numPoints == 0);
+        SetNegativeInfinity();
+        if (!pointArray)
+            return;
+        for (int i = 0; i < numPoints; ++i)
+            Enclose(pointArray[i]);
+    }
+
+    Vector3 AABB::GetRandomPointInside() const {
+
+    }
+
+    void AABB::SetNegativeInfinity() {
+        minPoint = Vector3::Infinity;
+        maxPoint = Vector3::NegativeInfinity;
+    }
+
+    void AABB::Enclose(const Vector3& point) {
+        minPoint = Vector3::Min(minPoint, point);
+        maxPoint = Vector3::Max(maxPoint, point);
+    }
+
+    void AABB::Enclose(const Vector3& aabbMinPt, const Vector3& aabbMaxPt)
+    {
+        minPoint = Vector3::Min(minPoint, aabbMinPt);
+        maxPoint = Vector3::Max(maxPoint, aabbMaxPt);
+    }
+
+    void AABB::Enclose(const LineSegment& lineSegment)
+    {
+       Enclose(Vector3::Min(lineSegment.A, lineSegment.B), Vector3::Max(lineSegment.A, lineSegment.B));
+    }
+
+    void AABB::Enclose(const OBB& obb)
+    {
+        Vector3 absAxis0 = obb.axis[0].Abs();
+        Vector3 absAxis1 = obb.axis[1].Abs();
+        Vector3 absAxis2 = obb.axis[2].Abs();
+        Vector3 d = obb.r.x * absAxis0 + obb.r.y * absAxis1 + obb.r.z * absAxis2;
+    }
+
+}

src/J3ML/Geometry/Capsule.cpp

@@ -1,6 +1,7 @@
 #include <J3ML/Geometry/Capsule.h>
 
-namespace Geometry
+namespace J3ML::Geometry
 {
 
+    Capsule::Capsule() : l() {}
 }

src/J3ML/Geometry/Frustum.cpp

@@ -1,6 +1,6 @@
 #include <J3ML/Geometry/Frustum.h>
 
-namespace Geometry
+namespace J3ML::Geometry
 {
     Frustum Frustum::CreateFrustumFromCamera(const CoordinateFrame &cam, float aspect, float fovY, float zNear, float zFar) {
         Frustum frustum;

src/J3ML/Geometry/LineSegment.cpp

@@ -1,5 +1,11 @@
 #include <J3ML/Geometry/LineSegment.h>
 
-namespace Geometry {
+namespace J3ML::Geometry {
 
+    LineSegment::LineSegment(const Vector3 &a, const Vector3 &b) : A(a), B(b)
+    {
+
+    }
+
+    LineSegment::LineSegment() {}
 }

src/J3ML/LinearAlgebra/AxisAngle.cpp

@@ -1,6 +1,6 @@
 #include <J3ML/LinearAlgebra/AxisAngle.h>
 #include <J3ML/LinearAlgebra/Quaternion.h>
-namespace LinearAlgebra {
+namespace J3ML::LinearAlgebra {
 
     AxisAngle::AxisAngle() : axis(Vector3::Zero) {}
 

src/J3ML/LinearAlgebra/EulerAngle.cpp

@@ -3,50 +3,49 @@
 #include <algorithm>
 
 
-#pragma region EulerAngle
-namespace LinearAlgebra {
-EulerAngle::EulerAngle(float pitch, float yaw, float roll): pitch(pitch), yaw(yaw), roll(roll)
-{}
+namespace J3ML::LinearAlgebra {
+    EulerAngle::EulerAngle(float pitch, float yaw, float roll): pitch(pitch), yaw(yaw), roll(roll)
+    {}
 
-float EulerAngle::GetPitch(float pitch_limit) const
-{ return std::clamp( std::remainderf(pitch,360.f), -pitch_limit, pitch_limit); }
+    float EulerAngle::GetPitch(float pitch_limit) const
+    { return std::clamp( std::remainderf(pitch,360.f), -pitch_limit, pitch_limit); }
 
-float EulerAngle::GetYaw(float yaw_limit) const
-{ return std::clamp(std::remainderf(yaw, 360.f), -yaw_limit, yaw_limit);   }
+    float EulerAngle::GetYaw(float yaw_limit) const
+    { return std::clamp(std::remainderf(yaw, 360.f), -yaw_limit, yaw_limit);   }
 
-float EulerAngle::GetRoll(float pitch_limit) const
-{ return std::clamp( std::remainderf(pitch,360.f), -pitch_limit, pitch_limit); }
+    float EulerAngle::GetRoll(float pitch_limit) const
+    { return std::clamp( std::remainderf(pitch,360.f), -pitch_limit, pitch_limit); }
 
-bool EulerAngle::operator==(const EulerAngle& a) const
-{
-    return (pitch == a.pitch) && (yaw == a.yaw) && (roll == a.roll);
-}
+    bool EulerAngle::operator==(const EulerAngle& a) const
+    {
+        return (pitch == a.pitch) && (yaw == a.yaw) && (roll == a.roll);
+    }
 
-void EulerAngle::clamp()
-{
-    if (this->pitch > 89.0f)
-        this->pitch = 89.0f;
-    if (this->pitch <= -89.0f)
-        this->pitch = -89.0f;
-    //TODO: Make this entirely seamless by getting the amount they rotated passed -180 and +180 by.
-    if (this->yaw <= -180.0f)
-        this->yaw = 180.0f;
-    if (this->yaw >= 180.01f)
-        this->yaw = -179.9f;
-    if (this->roll >= 360.0f)
-        this->roll = 0.0;
-    if (this->roll <= -360.0f)
-        this->roll = 0.0;
-}
+    void EulerAngle::clamp()
+    {
+        if (this->pitch > 89.0f)
+            this->pitch = 89.0f;
+        if (this->pitch <= -89.0f)
+            this->pitch = -89.0f;
+        //TODO: Make this entirely seamless by getting the amount they rotated passed -180 and +180 by.
+        if (this->yaw <= -180.0f)
+            this->yaw = 180.0f;
+        if (this->yaw >= 180.01f)
+            this->yaw = -179.9f;
+        if (this->roll >= 360.0f)
+            this->roll = 0.0;
+        if (this->roll <= -360.0f)
+            this->roll = 0.0;
+    }
 
-EulerAngle EulerAngle::movementAngle() const
-{
-    EulerAngle a;
-    a.pitch = (cos(Math::Radians(yaw)) * cos(Math::Radians(pitch)));
-    a.yaw = -sin(Math::Radians(pitch));
-    a.roll = (sin(Math::Radians(yaw)) * cos(Math::Radians(pitch)));
-    return a;
-}
+    EulerAngle EulerAngle::movementAngle() const
+    {
+        EulerAngle a;
+        a.pitch = (cos(Math::Radians(yaw)) * cos(Math::Radians(pitch)));
+        a.yaw = -sin(Math::Radians(pitch));
+        a.roll = (sin(Math::Radians(yaw)) * cos(Math::Radians(pitch)));
+        return a;
+    }
 
     EulerAngle::EulerAngle() : pitch(0), yaw(0), roll(0) {}
 }

src/J3ML/LinearAlgebra/Matrix2x2.cpp

@@ -1,6 +1,6 @@
 #include <J3ML/LinearAlgebra/Matrix2x2.h>
 
-namespace LinearAlgebra {
+namespace J3ML::LinearAlgebra {
 
     Vector2 Matrix2x2::GetRow(int index) const {
         float x = this->elems[index][0];

src/J3ML/LinearAlgebra/Matrix3x3.cpp

@@ -1,7 +1,7 @@
 #include <J3ML/LinearAlgebra/Matrix3x3.h>
 #include <cmath>
 
-namespace LinearAlgebra {
+namespace J3ML::LinearAlgebra {
 
     const Matrix3x3 Matrix3x3::Zero = Matrix3x3(0, 0, 0, 0, 0, 0, 0, 0, 0);
     const Matrix3x3 Matrix3x3::Identity = Matrix3x3(1, 0, 0, 0, 1, 0, 0, 0, 1);
@@ -296,5 +296,71 @@ namespace LinearAlgebra {
         };
     }
 
+    float &Matrix3x3::At(int row, int col) {
+        return elems[row][col];
+    }
+
+    Vector3 Matrix3x3::WorldZ() const {
+        return GetColumn(2);
+    }
+
+    Vector3 Matrix3x3::WorldY() const {
+        return GetColumn(1);
+    }
+
+    Vector3 Matrix3x3::WorldX() const {
+        return GetColumn(0);
+    }
+
+    Matrix3x3 Matrix3x3::FromRS(const Quaternion &rotate, const Vector3 &scale) {
+        return Matrix3x3(rotate) * Matrix3x3::FromScale(scale);
+    }
+
+    Matrix3x3 Matrix3x3::FromRS(const Matrix3x3 &rotate, const Vector3 &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);
+    }
+
 }
 

src/J3ML/LinearAlgebra/Matrix4x4.cpp

@@ -1,7 +1,7 @@
 #include <J3ML/LinearAlgebra/Matrix4x4.h>
 #include <J3ML/LinearAlgebra/Vector4.h>
 
-namespace LinearAlgebra {
+namespace J3ML::LinearAlgebra {
     const Matrix4x4 Matrix4x4::Zero = Matrix4x4(0);
     const Matrix4x4 Matrix4x4::Identity = Matrix4x4({1,0,0,0}, {0,1,0,0}, {0,0,1,0}, {0,0,0,1});
     const Matrix4x4 Matrix4x4::NaN = Matrix4x4(NAN);
@@ -90,11 +90,8 @@ namespace LinearAlgebra {
         elems[2][3] = offset.z;
     }
 
-    void Matrix4x4::SetRotatePart(const Quaternion &q) {
-        SetMatrixRotatePart(*this, q);
-    }
 
-    void Matrix4x4::SetMatrixRotatePart(Matrix4x4 &m, const Quaternion& q)
+    void Matrix4x4::SetRotatePart(const Quaternion& q)
     {
         // See e.g. http://www.geometrictools.com/Documentation/LinearAlgebraicQuaternions.pdf .
         const float x = q.x;
@@ -106,6 +103,15 @@ namespace LinearAlgebra {
         elems[2][0] =     2*(x*z - y*w); elems[2][1] =     2*(y*z + x*w); elems[2][2] = 1 - 2*(x*x + y*y);
     }
 
+    void Matrix4x4::Set3x3Part(const Matrix3x3& r)
+    {
+        At(0, 0) = r[0][0]; At(0, 1) = r[0][1]; At(0, 2) = r[0][2];
+        At(1, 0) = r[1][0]; At(1, 1) = r[1][1]; At(1, 2) = r[1][2];
+        At(2, 0) = r[2][0]; At(2, 1) = r[2][1]; At(2, 2) = r[2][2];
+    }
+
+
+
     void Matrix4x4::SetRow(int row, const Vector3 &rowVector, float m_r3) {
         SetRow(row, rowVector.x, rowVector.y, rowVector.z, m_r3);
     }
@@ -224,4 +230,288 @@ namespace LinearAlgebra {
     }
 
     Matrix4x4 Matrix4x4::operator+() const { return *this; }
+
+    Matrix4x4 Matrix4x4::FromTranslation(const Vector3 &rhs) {
+        return Matrix4x4(1.f, 0, 0, rhs.x,
+                         0, 1.f, 0, rhs.y,
+                         0, 0, 1.f, rhs.z,
+                         0, 0, 0,     1.f);
+    }
+
+    Matrix4x4 Matrix4x4::Translate(const Vector3 &rhs) const {
+        return *this * FromTranslation(rhs);
+    }
+
+    Vector3 Matrix4x4::Transform(const Vector3 &rhs) const {
+        return Transform(rhs.x, rhs.y, rhs.z);
+    }
+
+    Vector3 Matrix4x4::Transform(float tx, float ty, float tz) const {
+        return Vector3(At(0, 0) * tx + At(0, 1) * ty + At(0, 2) * tz + At(0, 3),
+                       At(1, 0) * tx + At(1, 1) * ty + At(1, 2) * tz + At(1, 3),
+                       At(2, 0) * tx + At(2, 1) * ty + At(2, 2) * tz + At(2, 3));
+    }
+
+    Vector2 Matrix4x4::Transform(float tx, float ty) const {
+        return Vector2(At(0, 0) * tx + At(0, 1) * ty + At(0, 2) + At(0, 3),
+                       At(1, 0) * tx + At(1, 1) * ty + At(1, 2) + At(1, 3));
+    }
+
+    Vector2 Matrix4x4::Transform(const Vector2 &rhs) const {
+        return Transform(rhs.x, rhs.y);
+    }
+
+    Matrix4x4 &Matrix4x4::operator=(const Matrix3x3 &rhs) {
+        Set3x3Part(rhs);
+        SetTranslatePart(0,0,0);
+        SetRow(3, 0, 0, 0, 1);
+        return *this;
+    }
+
+    Matrix4x4 &Matrix4x4::operator=(const Quaternion &rhs) {
+        *this = rhs.ToMatrix4x4();
+        return *this;
+    }
+
+    float &Matrix4x4::At(int row, int col) {
+        return elems[row][col];
+    }
+
+    Matrix4x4 Matrix4x4::Inverse() const {
+        // Compute the inverse directly using Cramer's rule
+        // Warning: This method is numerically very unstable!
+        float d = Determinant();
+
+        d = 1.f / d;
+
+        float a11 = At(0, 0);float a12 = At(0, 1);float a13 = At(0, 2);float a14 = At(0, 3);
+        float a21 = At(1, 0);float a22 = At(1, 1);float a23 = At(1, 2);float a24 = At(1, 3);
+        float a31 = At(2, 0);float a32 = At(2, 1);float a33 = At(2, 2);float a34 = At(2, 3);
+        float a41 = At(3, 0);float a42 = At(3, 1);float a43 = At(3, 2);float a44 = At(3, 3);
+
+        Matrix4x4 i = {
+                d * (a22*a33*a44 + a23*a34*a42 + a24*a32*a43 - a22*a34*a43 - a23*a32*a44 - a24*a33*a42),
+                d * (a12*a34*a43 + a13*a32*a44 + a14*a33*a42 - a12*a33*a44 - a13*a34*a42 - a14*a32*a43),
+                d * (a12*a23*a44 + a13*a24*a42 + a14*a22*a43 - a12*a24*a43 - a13*a22*a44 - a14*a23*a42),
+                d * (a12*a24*a33 + a13*a22*a34 + a14*a23*a32 - a12*a23*a34 - a13*a24*a32 - a14*a22*a33),
+                d * (a21*a34*a43 + a23*a31*a44 + a24*a33*a41 - a21*a33*a44 - a23*a34*a41 - a24*a31*a43),
+                d * (a11*a33*a44 + a13*a34*a41 + a14*a31*a43 - a11*a34*a43 - a13*a31*a44 - a14*a33*a41),
+                d * (a11*a24*a43 + a13*a21*a44 + a14*a23*a41 - a11*a23*a44 - a13*a24*a41 - a14*a21*a43),
+                d * (a11*a23*a34 + a13*a24*a31 + a14*a21*a33 - a11*a24*a33 - a13*a21*a34 - a14*a23*a31),
+                d * (a21*a32*a44 + a22*a34*a41 + a24*a31*a42 - a21*a34*a42 - a22*a31*a44 - a24*a32*a41),
+                d * (a11*a34*a42 + a12*a31*a44 + a14*a32*a41 - a11*a32*a44 - a12*a34*a41 - a14*a31*a42),
+                d * (a11*a22*a44 + a12*a24*a41 + a14*a21*a42 - a11*a24*a42 - a12*a21*a44 - a14*a22*a41),
+                d * (a11*a24*a32 + a12*a21*a34 + a14*a22*a31 - a11*a22*a34 - a12*a24*a31 - a14*a21*a32),
+                d * (a21*a33*a42 + a22*a31*a43 + a23*a32*a41 - a21*a32*a43 - a22*a33*a41 - a23*a31*a42),
+                d * (a11*a32*a43 + a12*a33*a41 + a13*a31*a42 - a11*a33*a42 - a12*a31*a43 - a13*a32*a41),
+                d * (a11*a23*a42 + a12*a21*a43 + a13*a22*a41 - a11*a22*a43 - a12*a23*a41 - a13*a21*a42),
+                d * (a11*a22*a33 + a12*a23*a31 + a13*a21*a32 - a11*a23*a32 - a12*a21*a33 - a13*a22*a31)
+        };
+        return i;
+    }
+
+    float Matrix4x4::Minor(int i, int j) const {
+        int r0 = SKIPNUM(0, i);
+        int r1 = SKIPNUM(1, i);
+        int r2 = SKIPNUM(2, i);
+        int c0 = SKIPNUM(0, j);
+        int c1 = SKIPNUM(1, j);
+        int c2 = SKIPNUM(2, j);
+
+        float a = At(r0, c0);
+        float b = At(r0, c1);
+        float c = At(r0, c2);
+        float d = At(r1, c0);
+        float e = At(r1, c1);
+        float f = At(r1, c2);
+        float g = At(r2, c0);
+        float h = At(r2, c1);
+        float k = At(r2, c2);
+
+        return a*e*k + b*f*g + c*d*h - a*f*h - b*d*k - c*e*g;
+    }
+
+    float Matrix4x4::Determinant() const {
+        return At(0, 0) * Minor(0,0) - At(0, 1) * Minor(0,1) + At(0, 2) * Minor(0,2) - At(0, 3) * Minor(0,3);
+    }
+
+    float Matrix4x4::Determinant3x3() const {
+
+        const float a = elems[0][0];
+        const float b = elems[0][1];
+        const float c = elems[0][2];
+        const float d = elems[1][0];
+        const float e = elems[1][1];
+        const float f = elems[1][2];
+        const float g = elems[2][0];
+        const float h = elems[2][1];
+        const float i = elems[2][2];
+
+        return a*e*i + b*f*g + c*d*h - a*f*h - b*d*i - c*e*g;
+    }
+
+    Matrix3x3 Matrix4x4::GetRotatePart() const {
+        return Matrix3x3 {
+                At(0, 0), At(0, 1), At(0, 2),
+                At(1, 0), At(1, 1), At(1, 2),
+                At(2, 0), At(2, 1), At(2, 2)
+        };
+    }
+
+    Matrix4x4 Matrix4x4::Transpose() const {
+        Matrix4x4 copy;
+        copy.elems[0][0] = elems[0][0]; copy.elems[0][1] = elems[1][0]; copy.elems[0][2] = elems[2][0]; copy.elems[0][3] = elems[3][0];
+        copy.elems[1][0] = elems[0][1]; copy.elems[1][1] = elems[1][1]; copy.elems[1][2] = elems[2][1]; copy.elems[1][3] = elems[3][1];
+        copy.elems[2][0] = elems[0][2]; copy.elems[2][1] = elems[1][2]; copy.elems[2][2] = elems[2][2]; copy.elems[2][3] = elems[3][2];
+        copy.elems[3][0] = elems[0][3]; copy.elems[3][1] = elems[1][3]; copy.elems[3][2] = elems[2][3]; copy.elems[3][3] = elems[3][3];
+        return copy;
+    }
+
+    Vector4 Matrix4x4::Diagonal() const {
+        return Vector4{At(0, 0), At(1,1), At(2,2), At(3,3)};
+    }
+
+    Vector3 Matrix4x4::Diagonal3() const {
+        return Vector3 { At(0, 0), At(1,1), At(2,2) };
+    }
+
+    Vector3 Matrix4x4::WorldX() const {
+        return GetColumn3(0);
+    }
+
+    Vector3 Matrix4x4::WorldY() const {
+        return GetColumn3(1);
+    }
+
+    Vector3 Matrix4x4::WorldZ() const {
+        return GetColumn3(2);
+    }
+
+    bool Matrix4x4::IsFinite() const {
+        for(int iy = 0; iy < Rows; ++iy)
+            for(int ix = 0; ix < Cols; ++ix)
+                if (!std::isfinite(elems[iy][ix]))
+                    return false;
+        return true;
+    }
+
+    Vector3 Matrix4x4::GetColumn3(int index) const {
+        return Vector3{At(0, index), At(1, index), At(2, index)};
+    }
+
+    Vector2 Matrix4x4::operator*(const Vector2 &rhs) const { return this->Transform(rhs);}
+
+    Vector3 Matrix4x4::operator*(const Vector3 &rhs) const { return this->Transform(rhs);}
+
+    Vector4 Matrix4x4::operator*(const Vector4 &rhs) const { return this->Transform(rhs);}
+
+    Vector4 Matrix4x4::Transform(float tx, float ty, float tz, float tw) const {
+        return Transform({tx, ty, tz, tw});
+    }
+
+    Vector4 Matrix4x4::Transform(const Vector4 &rhs) const {
+        return Vector4(At(0, 0) * rhs.x + At(0, 1) * rhs.y + At(0, 2) * rhs.z + At(0, 3) * rhs.w,
+                       At(1, 0) * rhs.x + At(1, 1) * rhs.y + At(1, 2) * rhs.z + At(1, 3) * rhs.w,
+                       At(2, 0) * rhs.x + At(2, 1) * rhs.y + At(2, 2) * rhs.z + At(2, 3) * rhs.w,
+                       At(3, 0) * rhs.x + At(3, 1) * rhs.y + At(3, 2) * rhs.z + At(3, 3) * rhs.w);
+    }
+
+    Vector3 Matrix4x4::GetTranslatePart() const {
+        return GetColumn3(3);
+    }
+
+    Matrix4x4
+    Matrix4x4::LookAt(const Vector3 &localFwd, const Vector3 &targetDir, const Vector3 &localUp, const Vector3 &worldUp) {
+        Matrix4x4 m;
+        m.Set3x3Part(Matrix3x3::LookAt(localFwd, targetDir, localUp, worldUp));
+        m.SetTranslatePart(0,0,0);
+        m.SetRow(3, 0,0,0,1);
+        return m;
+    }
+
+    Vector4 Matrix4x4::GetRow(int index) const {
+        return { At(index, 0), At(index, 1), At(index, 2), At(index, 3)};
+    }
+
+    Vector4 Matrix4x4::GetColumn(int index) const {
+        return { At(0, index), At(1, index), At(2, index), At(3, index)};
+    }
+
+    Vector3 Matrix4x4::GetRow3(int index) const {
+        return Vector3{ At(index, 0), At(index, 1), At(index, 2)};
+    }
+
+    void Matrix4x4::SwapColumns(int col1, int col2) {
+        Swap(At(0, col1), At(0, col2));
+        Swap(At(1, col1), At(1, col2));
+        Swap(At(2, col1), At(2, col2));
+        Swap(At(3, col1), At(3, col2));
+    }
+
+    void Matrix4x4::SwapRows(int row1, int row2) {
+        Swap(At(row1, 0), At(row2, 0));
+        Swap(At(row1, 1), At(row2, 1));
+        Swap(At(row1, 2), At(row2, 2));
+        Swap(At(row1, 3), At(row2, 3));
+    }
+
+    void Matrix4x4::SwapRows3(int row1, int row2) {
+        Swap(At(row1, 0), At(row2, 0));
+        Swap(At(row1, 1), At(row2, 1));
+        Swap(At(row1, 2), At(row2, 2));
+    }
+
+    void Matrix4x4::Pivot() {
+        int rowIndex = 0;
+
+        for(int col = 0; col < Cols; ++col)
+        {
+            int greatest = rowIndex;
+
+            // find the rowIndex k with k >= 1 for which Mkj has the largest absolute value.
+            for(int i = rowIndex; i < Rows; ++i)
+                if (std::abs(At(i, col)) > std::abs(At(greatest, col)))
+                    greatest = i;
+
+            if (std::abs(At(greatest, col)) != 0)
+            {
+                if (rowIndex != greatest)
+                    SwapRows(rowIndex, greatest); // the greatest now in rowIndex
+
+                ScaleRow(rowIndex, 1.f/At(rowIndex, col));
+
+                for(int r = 0; r < Rows; ++r)
+                    if (r != rowIndex)
+                        SetRow(r, GetRow(r) - GetRow(rowIndex) * At(r, col));
+
+                ++rowIndex;
+            }
+        }
+    }
+
+    void Matrix4x4::ScaleColumn3(int col, float scalar) {
+        At(0, col) *= scalar;
+        At(1, col) *= scalar;
+        At(2, col) *= scalar;
+    }
+
+    void Matrix4x4::ScaleColumn(int col, float scalar) {
+        At(0, col) *= scalar;
+        At(1, col) *= scalar;
+        At(2, col) *= scalar;
+        At(3, col) *= scalar;
+    }
+
+    void Matrix4x4::ScaleRow3(int row, float scalar) {
+        At(row, 0) *= scalar;
+        At(row, 1) *= scalar;
+        At(row, 2) *= scalar;
+    }
+
+    void Matrix4x4::ScaleRow(int row, float scalar) {
+        At(row, 0) *= scalar;
+        At(row, 1) *= scalar;
+        At(row, 2) *= scalar;
+        At(row, 3) *= scalar;
+    }
 }

src/J3ML/LinearAlgebra/Quaternion.cpp

@@ -4,7 +4,7 @@
 #include <J3ML/LinearAlgebra/Matrix4x4.h>
 #include <J3ML/LinearAlgebra/Quaternion.h>
 
-namespace LinearAlgebra {
+namespace J3ML::LinearAlgebra {
     Quaternion Quaternion::operator-() const
     {
         return {-x, -y, -z, -w};

src/J3ML/LinearAlgebra/Transform2D.cpp

@@ -1,6 +1,6 @@
 #include <J3ML/LinearAlgebra/Transform2D.h>
 
-namespace LinearAlgebra {
+namespace J3ML::LinearAlgebra {
 
     const Transform2D Transform2D::Identity = Transform2D({0, 0}, {1, 1}, {0,0}, {0,0}, 0);
     const Transform2D Transform2D::FlipX    = Transform2D({0, 0}, {-1, 1}, {0,0}, {0,0}, 0);

src/J3ML/LinearAlgebra/Vector2.cpp

@@ -4,7 +4,7 @@
 #include <valarray>
 #include <iostream>
 
-namespace LinearAlgebra {
+namespace J3ML::LinearAlgebra {
 
     Vector2::Vector2(): x(0), y(0)
     {}
@@ -15,13 +15,21 @@ namespace LinearAlgebra {
     Vector2::Vector2(const Vector2& rhs): x(rhs.x), y(rhs.y)
     {}
 
-    float Vector2::operator[](std::size_t index)
+    float Vector2::operator[](std::size_t index) const
     {
         assert(index < 2);
         if (index == 0) return x;
         if (index == 1) return y;
         return 0;
     }
+
+    float &Vector2::operator[](std::size_t index)
+    {
+        assert(index < 2);
+        if (index == 0) return x;
+        if (index == 1) return y;
+    }
+
     bool Vector2::IsWithinMarginOfError(const Vector2& rhs, float margin) const
     {
         return this->Distance(rhs) <= margin;
@@ -253,4 +261,6 @@ namespace LinearAlgebra {
     Vector2 Vector2::Div(const Vector2 &v) const {
         return {this->x/v.x, this->y/v.y};
     }
+
+    Vector2 Vector2::Abs() const { return {std::abs(x), std::abs(y)};}
 }

src/J3ML/LinearAlgebra/Vector3.cpp

@@ -3,9 +3,9 @@
 #include <cassert>
 #include <cmath>
 
-namespace LinearAlgebra {
+namespace J3ML::LinearAlgebra {
+
 
-#pragma region vector3
 
     const Vector3 Vector3::Zero     = {0,0,0};
     const Vector3 Vector3::Up       = {0, -1, 0};
@@ -15,6 +15,8 @@ namespace LinearAlgebra {
     const Vector3 Vector3::Forward  = {0, 0, -1};
     const Vector3 Vector3::Backward = {0, 0, 1};
     const Vector3 Vector3::NaN      = {NAN, NAN, NAN};
+    const Vector3 Vector3::Infinity = {INFINITY, INFINITY, INFINITY};
+    const Vector3 Vector3::NegativeInfinity = {-INFINITY, -INFINITY, -INFINITY};
 
     Vector3 Vector3::operator+(const Vector3& rhs) const
     {
@@ -80,6 +82,14 @@ namespace LinearAlgebra {
         return 0;
     }
 
+    float &Vector3::operator[](std::size_t index)
+    {
+        assert(index < 3);
+        if (index == 0) return x;
+        if (index == 1) return y;
+        if (index == 2) return z;
+    }
+
     bool Vector3::IsWithinMarginOfError(const Vector3& rhs, float margin) const
     {
         return this->Distance(rhs) <= margin;
@@ -308,5 +318,9 @@ namespace LinearAlgebra {
         return {x, y, z};
     }
 
-#pragma endregion
+    Vector3 Vector3::Abs() const {
+        return {std::abs(x), std::abs(y), std::abs(z)};
+    }
+
+
 }

src/J3ML/LinearAlgebra/Vector4.cpp

@@ -7,7 +7,7 @@
 #include <cmath>
 #include <algorithm>
 
-namespace LinearAlgebra {
+namespace J3ML::LinearAlgebra {
 
     const Vector4 Vector4::Zero = {0,0,0,0};
     const Vector4 Vector4::NaN = {NAN, NAN, NAN, NAN};
@@ -141,6 +141,15 @@ Vector4 Vector4::operator-(const Vector4& rhs) const
 
     }
 
+    Vector4 &Vector4::operator=(const Vector4 &rhs) {
+        x = rhs.x;
+        y = rhs.y;
+        z = rhs.z;
+        w = rhs.w;
+
+        return *this;
+    }
+
 
 }
 #pragma endregion

tests/LinearAlgebra/Vector2Tests.cpp

@@ -1,7 +1,7 @@
 #include <gtest/gtest.h>
 #include <J3ML/LinearAlgebra/Vector2.h>
 
-using Vector2 = LinearAlgebra::Vector2;
+using J3ML::LinearAlgebra::Vector2;
 
 TEST(Vector2Test, V2_Constructor_Default)
 {

tests/LinearAlgebra/Vector3Tests.cpp

@@ -1,7 +1,7 @@
 #include <gtest/gtest.h>
 #include <J3ML/LinearAlgebra/Vector3.h>
 
-using Vector3 = LinearAlgebra::Vector3;
+using J3ML::LinearAlgebra::Vector3;
 
 void EXPECT_V3_EQ(const Vector3& lhs, const Vector3& rhs)
 {
@@ -185,11 +185,12 @@ TEST(Vector3Test, V3_Lerp)
     EXPECT_V3_EQ(Start.Lerp(Finish, Percent), ExpectedResult);
 }
 TEST(Vector3Test, V3_AngleBetween) {
+    using J3ML::LinearAlgebra::Angle2D;
     Vector3 A{ .5f, .5f, .5f};
     Vector3 B {.25f, .75f, .25f};
     A = A.Normalize();
     B = B.Normalize();
-    LinearAlgebra::Angle2D ExpectedResult {-0.69791365, -2.3561945};
+    Angle2D ExpectedResult {-0.69791365, -2.3561945};
     std::cout << A.AngleBetween(B).x << ", " << A.AngleBetween(B).y << "";
     auto angle = A.AngleBetween(B);
     EXPECT_FLOAT_EQ(angle.x, ExpectedResult.x);

tests/LinearAlgebra/Vector4Tests.cpp

@@ -1,7 +1,7 @@
 #include <gtest/gtest.h>
 #include <J3ML/LinearAlgebra/Vector4.h>
 
-using Vector4 = LinearAlgebra::Vector4;
+using Vector4 = J3ML::LinearAlgebra::Vector4;
 
 
 void EXPECT_V4_EQ(const Vector4& lhs, const Vector4& rhs)