diff -r 53ef954e90b6 -r d2a9c31353f7 geometry.h
--- a/geometry.h	Wed Jan 16 15:45:19 2008 +0000
+++ b/geometry.h	Mon Jul 14 11:21:10 2008 +0000
@@ -10,4 +10,25 @@
 
 QPointF normalize (const QPointF &p);
 
+
+qreal dotProduct (const QPointF &a, const QPointF &b);
+
+class PolygonCollisionResult {
+public:
+    // Are the polygons going to intersect forward in time?
+    bool willIntersect;
+
+    // Are the polygons currently intersecting?
+    bool intersect;
+
+    // The translation to apply to the first polygon to push the polygons apart.
+    QPointF minTranslation;
+};
+
+
+void ProjectPolygon(QPointF axis, QPolygonF polygon, qreal &min, qreal &max) ;
+qreal intervalDistance(qreal minA, qreal maxA, qreal minB, qreal maxB);
+PolygonCollisionResult PolygonCollision(QPolygonF polygonA, 
+                              QPolygonF polygonB, QPointF velocity);
+
 #endif