[OpenLayers-Users] Add layers drawing points

[Lucas Eskopinski]

Hi,

I have a problem adding WMS Layer (from GeoServer) and creating points with OpenLayers. When I change the zoom level, the point that was on a road (layer WMS from GeoServer) appears elsewhere and not on the road.

I think it is a distortion problem in the map window, it presents different projection behaviors for diffent zoom levels.

http://img19.imageshack.us/img19/3610/figura01.png
http://img19.imageshack.us/img19/4426/figura02.png

My configuration:

- PostGIS: my table :  SRID: 4326
  ...CONSTRAINT enforce_srid_the_geom CHECK (srid(the_geom) = 4326)
- GeoServer: my layer: SRS: 4326
    ...SRS handling: Force declared SRS (native will be ignored)
- OpenLayers:  srs: 'EPSG:4326'
    layer = new OpenLayers.Layer.WMS(
        "topp:ruas_rs - Tiled", "http://localhost:8080/geoserver/wms",
   {
     layers: 'topp:ruas_rs', styles: '', height: '550', width: '350', srs: 'EPSG:4326', format:         format, tiled: 'true', tilesOrigin : "-51.31199340820311,-30.310599613189684"
   },
   {buffer: 0} 
);
----------------
var SinglePoint = OpenLayers.Class.create();
SinglePoint.prototype = OpenLayers.Class.inherit(OpenLayers.Handler.Point, {
 createFeature: function(evt) {
   this.control.layer.removeFeatures(this.control.layer.features);
   OpenLayers.Handler.Point.prototype.createFeature.apply(this, arguments);
}
});
            
var start_style = OpenLayers.Util.extend({}, OpenLayers.Feature.Vector.style['default']);
start_style.externalGraphic = "images/start.png";
start_style.graphicWidth = 18;
start_style.graphicHeight = 26;
start_style.graphicYOffset = -26;
start_style.graphicOpacity = 1;
var stop_style = OpenLayers.Util.extend({}, OpenLayers.Feature.Vector.style['default']);
stop_style.externalGraphic = "images/stop.png";
stop_style.graphicWidth = 18;
stop_style.graphicHeight = 26;
stop_style.graphicYOffset = -26;
stop_style.graphicOpacity = 1;
            
var result_style = OpenLayers.Util.extend({}, OpenLayers.Feature.Vector.style['default']);
result_style.strokeWidth = 3;
result_style.strokeColor = "#ff0000";
result_style.fillOpacity = 0;
start = new OpenLayers.Layer.Vector("Start point", {style: start_style});
stop = new OpenLayers.Layer.Vector("End point", {style: stop_style});
result = new OpenLayers.Layer.Vector("Routing results", {style: result_style});
                
map.addLayers([layer, start, stop, result]);            
// controls
controls = {
  start: new OpenLayers.Control.DrawFeature(start, SinglePoint),
  stop: new OpenLayers.Control.DrawFeature(stop, SinglePoint)
}
for (var key in controls) {
  map.addControl(controls[key]);
}
function compute() { 
  var startPoint = start.features[0]; 
  var stopPoint = stop.features[0]; 
                                
  if (startPoint && stopPoint) { 
    var result = { 
        startpoint: startPoint.geometry.x + ' ' + startPoint.geometry.y, 
            finalpoint: stopPoint.geometry.x + ' ' + stopPoint.geometry.y, 
        method: OpenLayers.Util.getElement('method').value, region: "teste", srid: "4326" 
    }; 
    var request = OpenLayers.Request.GET({
        url: "http://localhost:8080/application-test/RoutingServlet",
        params: result, headers: {"Content-Type": "text/plain"},
        callback: displayRoute
    });  
    }
 } 
function displayRoute(response) { 
 if (response && response.responseXML) {
    // erase the previous results
    result.removeFeatures(result.features);
    var edges = response.responseXML.getElementsByTagName('edge');
    var features = [];
    for (var i = 0; i < edges.length; i++) {
    var wkt = (edges[i].getElementsByTagName('wkt')[0].text);
    var geometry = parser.read(wkt);
    result.addFeatures(geometry);
    }                                  
  }
} 

Sorry, but my English is not so good.

Thanks.

Lucas Eskopinski.
-- 
View this message in context: http://n2.nabble.com/Add-layers-drawing-points-tp2653881p2653881.html
Sent from the OpenLayers Users mailing list archive at Nabble.com.