Is there an easy way to get the onScreen-coordinates of all visible Graphics objects?
Another thing you could try would be to use a 'hit test' on the graphics layers to find all graphics within a certain pixel tolerance of a screen point.
One overload of graphicsLayer.getGraphicIDs takes an x, y, as well as a pixel tolerance and max number of results. The tolerance is a square around the x, y point (such that a side of the square is 2*tolerance). You could set the max results to something high (depending on how many graphics you're expecting in your extent at one time) and the tolerance to be for example 1/2 the max(extentHeight, extentWidth). You could at least use this to reduce the number of graphics you're checking against the 'contains' in your code above.
~elise
Do you mean visible as in whether it's in the current map extent?
And what have you tried so far?
Yes I meant the current map extent, like in this screenshot. The Icons are in different GraphicsLayer.
The method I tried is to iterate over all graphics layer, iterate over all graphics, check if the geometry is in the current extent and then call the JMap.toScreenPoint() method. Here is a snippet of the code:
List<Point> coords = new ArrayList<Point>();
LayerList list = map.getLayers();
for (int i = list.size() - 1; i >= 0; i--) {
if (list.get(i) instanceof GraphicsLayer) {
GraphicsLayer layer = (GraphicsLayer) list.get(i);
if (layer.getGraphicIDs() != null && layer.getGraphicIDs().length > 0) {
int[] ids = layer.getGraphicIDs();
for (int j = 0; j < ids.length; j++) {
Graphic graphic = layer.getGraphic(ids);
com.esri.core.geometry.Geometry geometry = graphic.getGeometry();
if (com.esri.core.geometry.Geometry.isPoint(geometry.getType().a())) {
Point p = (Point) geometry;
Envelope extent = map.getExtent();
if (extent.contains(p)) {
Point screenPoint = map.toScreenPoint(p);
coords.add(screenPoint);
}
This works, but i hope there is an easier and perhaps faster way. Particularly for other geometry objects like polylines and polygons.
I need to call this method after every change of the map extent or change in the data.
My final solution is this:
int[] graphicIDs = layer.getGraphicIDs(map.getWidth() / 2, map.getHeight() / 2, Math.max(map.getWidth(), map.getHeight())/2);
if (graphicIDs != null && graphicIDs.length > 0) {
int[] ids = graphicIDs;
This works, but with with over 10000 objects on screen it takes a lot of time. It would be nice if the javadoc for getGraphicIDs(float x, float y, int tolerance) mentioned that the search tolerance is used for the sides of a square and not as radius for a circle.
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