restructured repository based on following standards:

https://github.com/HW-Core/directory-structure

modules/dep/g3dlite/include/G3D/Matrix2.h

@@ -0,0 +1,74 @@
+#ifndef G3D_Matrix2_h
+#define G3D_Matrix2_h
+
+#include "G3D/platform.h"
+#include "G3D/Vector2.h"
+
+namespace G3D {
+
+/** @beta */
+class Matrix2 {
+private:
+
+    float          data[2][2];
+
+public:
+
+    Matrix2() {
+        data[0][0] = 1.0f; data[0][1] = 0.0f;
+        data[1][0] = 0.0f; data[1][1] = 1.0f;
+    }
+
+    Matrix2(float v00, float v01, float v10, float v11) {
+        data[0][0] = v00; data[0][1] = v01;
+        data[1][0] = v10; data[1][1] = v11;
+    }
+
+    static Matrix2 identity() {
+        return Matrix2(1.0f, 0.0f, 0.0f, 1.0f);
+    }
+
+    Vector2 operator*(const Vector2& v) const {
+        return Vector2(data[0][0] * v[0] + data[0][1] * v[1],
+                       data[1][0] * v[0] + data[1][1] * v[1]);
+    }
+    
+    Matrix2 inverse() const {
+        return Matrix2(data[1][1], -data[0][1],
+                       -data[1][0], data[0][0]) * (1.0f / determinant());
+    }
+
+    Matrix2 transpose() const {
+        return Matrix2(data[0][0], data[1][0],
+                       data[0][1], data[1][1]);
+    }
+
+    float determinant() const {
+        return data[0][0] * data[1][1] - data[0][1] * data[1][0];
+    }
+
+    Matrix2 operator*(float f) const {
+        return Matrix2(data[0][0] * f, data[0][1] * f,
+                       data[1][0] * f, data[1][1] * f);
+    }
+
+    Matrix2 operator/(float f) const {
+        return Matrix2(data[0][0] / f, data[0][1] / f,
+                       data[1][0] / f, data[1][1] / f);
+    }
+
+    float* operator[](int i) {
+        debugAssert(i >= 0 && i <= 2);
+        return data[i];
+    }
+
+    const float* operator[](int i) const {
+        debugAssert(i >= 0 && i <= 1);
+        return data[i];
+    }
+
+};
+
+}
+
+#endif