some refactoring

hopefully improved rendering speed
added support to add .obj obstacles

mapview/2D/Painter.h

@@ -6,6 +6,7 @@
 
 #include <Indoor/geo/Point2.h>
 #include <Indoor/geo/Point3.h>
+#include <Indoor/geo/BBox2.h>
 
 #include "Scaler.h"
 
@@ -30,6 +31,22 @@ public:
 
 	int height() {return h;}
 
+	/** is the given point visible on screen? */
+	bool isVisible(const Point2 p) {
+		const float x = s.xms(p.x);
+		const float y = s.yms(p.y);
+		return (x >= 0 && y >= 0  && x < w && y < h);
+	}
+
+	/** is the given volume visible on screen? */
+	bool isVisible(const BBox2 bb) {
+		const BBox2 bbt(0,0,w,h);
+		BBox2 bbs;
+		bbs.add(s.xms(bb.getMin().x), s.yms(bb.getMin().y));	// y might be inverted! -> use the add() method to address this
+		bbs.add(s.xms(bb.getMax().x), s.yms(bb.getMax().y));	// y might be inverted! -> use the add() method to address this
+		return bbt.intersects(bbs);
+	}
+
 	void drawLine(const Point2 p1, const Point2 p2) {
 		p->drawLine(s.xms(p1.x), s.yms(p1.y), s.xms(p2.x), s.yms(p2.y));
 	}