restructured repository based on following standards:

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

modules/dep/g3dlite/source/Box2D.cpp

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+/**
+  @file Box.cpp
+  Box class
+
+  @maintainer Morgan McGuire, http://graphics.cs.williams.edu
+
+  @created 2001-06-02
+  @edited  2008-12-27
+*/
+
+#include "G3D/Box2D.h"
+#include "G3D/CoordinateFrame.h"
+#include "G3D/Rect2D.h"
+
+namespace G3D {
+
+bool Box2D::overlaps1Way(const Box2D& other) const {
+    for (int a = 0; a < 2; ++a) {
+        
+        float t = other.m_corner[0].dot(m_axisin[a]);
+
+        // Find the extent of box 2 on m_axisin a
+        float tMin = t;
+        float tMax = t;
+        
+        for (int c = 1; c < 4; ++c) {
+            t = other.m_corner[c].dot(m_axisin[a]);
+            
+            if (t < tMin) {
+                tMin = t;
+            } else if (t > tMax) {
+                tMax = t;
+            }
+        }
+        
+        // We have to subtract off the origin
+        
+        // See if [tMin, tMax] intersects [0, 1]
+        if ((tMin > 1 + origin[a]) || (tMax < origin[a])) {
+            // There was no intersection along this dimension;
+            // the boxes cannot possibly overlap.
+            return false;
+        }
+    }
+    
+    // There was no dimension along which there is no intersection.
+    // Therefore the boxes overlap.
+    return true;
+}
+
+
+void Box2D::computeAxes() {
+    m_axis[0] = m_corner[1] - m_corner[0]; 
+    m_axis[1] = m_corner[3] - m_corner[0]; 
+    
+    // Make the length of each m_axisin = 1/edge length so we know any
+    // dot product must be less than 1 to fall within the edge.
+    float len[2];
+    for (int a = 0; a < 2; ++a) {
+        float lenSq = m_axis[a].squaredLength();
+        m_axisin[a] = m_axis[a] / lenSq;
+        origin[a] = m_corner[0].dot(m_axisin[a]);
+        len[a] = sqrt(lenSq); 
+        m_axis[a] /= len[a];
+    }
+
+    // w * h
+    m_area = len[0] * len[1];
+    
+    
+    m_center = (m_corner[0] + m_corner[2]) * 0.5f;
+}
+
+
+Box2D::Box2D(const Vector2& center, float w, float h, float angle) {
+    Vector2 X( cos(angle), sin(angle));
+    Vector2 Y(-sin(angle), cos(angle));
+    
+    X *= w / 2;
+    Y *= h / 2;
+    
+    m_corner[0] = center - X - Y;
+    m_corner[1] = center + X - Y;
+    m_corner[2] = center + X + Y;
+    m_corner[3] = center - X + Y;
+    
+    computeAxes();
+}
+
+
+Box2D::Box2D(const AABox2D& b) {
+    for (int i = 0; i < 4; ++i) {
+        m_corner[i] = b.corner(i);
+    }
+    
+    computeAxes();
+}
+
+
+Box2D::Box2D(const Vector2& min, const Vector2& max) {
+    *this = Box2D(Rect2D::xyxy(min, max));
+}
+
+
+Box2D::Box2D(const CFrame& frame, Box2D& b) {
+    for (int i = 0; i < 4; ++i) {
+        m_corner[i] = frame.pointToWorldSpace(Vector3(b.corner(i), 0)).xy();
+    }
+    computeAxes();
+}
+
+   
+} // G3D