mapwidget.qml: add a couple of helpers

Add stopZoomAnimations(), which is really just a precaution
function to make sure we have stopped all animation of the
map before doing calculations! Since the animation *should*
be running in a separate thread, this would make sure the Map "center"
and "zoomLevel" properties do not change.

Add pointIsVisible(), which is a helper to determine
if a point created by map.fromCoordinate() method is inside
the viewport. fromCoordinate() has to be called without the
"false" (clip) flag for this to work.

Signed-off-by: Lubomir I. Ivanov <neolit123@gmail.com>

mobile-widgets/qml/MapWidget.qml

@@ -148,7 +148,17 @@ Item {
 			mapAnimationZoomOut.restart()
 		}
 
+		function pointIsVisible(pt) {
+			return !isNaN(pt.x)
+		}
+
+		function stopZoomAnimations() {
+			mapAnimationZoomIn.stop()
+			mapAnimationZoomOut.stop()
+		}
+
 		function centerOnCoordinate(coord) {
+			stopZoomAnimations()
 			newCenter = coord
 			if (coord.latitude === 0.0 && coord.longitude === 0.0) {
 				newZoom = 2.6
@@ -157,8 +167,8 @@ Item {
 				var zoomStored = zoomLevel
 				newZoomOut = zoomLevel
 				while (zoomLevel > minimumZoomLevel) {
-					var pt = fromCoordinate(coord, false)
+					var pt = fromCoordinate(coord)
-					if (pt.x > 0 && pt.y > 0 && pt.x < width && pt.y < height) {
+					if (pointIsVisible(pt)) {
 						newZoomOut = zoomLevel
 						break
 					}