fixed angle interpretation to be 90° at north

refs 303

org.fortiss.tooling.base.ui/trunk/src/org/fortiss/tooling/base/ui/utils/EllipseLayoutUtils.java

@@ -30,7 +30,7 @@ import org.fortiss.tooling.base.model.layout.ILayoutedModelElement;
  * @author hoelzl
  * @author $Author$
  * @version $Rev$
- * @ConQAT.Rating YELLOW Hash: 80B631B5B2032BFAD1D1161DC0549957
+ * @ConQAT.Rating YELLOW Hash: 8C0D9FE6F0557C583EE2EACDBEC6D146
  */
 public final class EllipseLayoutUtils {
 	/**
@@ -169,6 +169,9 @@ public final class EllipseLayoutUtils {
 	/**
 	 * Class for storing polar coordinates.
 	 * 
+	 * The angles are interpreted in the following way: 0: East; 90(pi/2):
+	 * North; 180(pi): West; 270(3/2pi): South
+	 * 
 	 * @author wandinger
 	 * @author hummel
 	 * @author $Author$
@@ -198,7 +201,7 @@ public final class EllipseLayoutUtils {
 		/** Returns a cartesian representation. */
 		public Point toCartesian() {
 			int x = (int) (distance * Math.cos(angle));
-			int y = (int) (distance * Math.sin(angle));
+			int y = (int) (distance * Math.sin(angle)) * (-1);
 			return new Point(x, y);
 		}
 	}