Made physics work

src/include/DataModelV2/PartInstance.h

@@ -54,6 +54,7 @@ public:
 	void setShape(Enum::Shape::Value shape);
 	void setChanged();
 	void setSurface(int face, Enum::SurfaceType::Value surface);
+	float getMass();
 
 	//Collision
 	bool collides(PartInstance * part);
@@ -70,4 +71,4 @@ private:
 	bool changed;
 	Box itemBox;
 	GLuint glList;
-};
+};