非常感謝lib的建議。我用https://github.com/bjornharrtell/jsts/blob/master/examples/overlay.html有:
var union = a.union(b);
var difference = a.difference(b);
結合形狀,使孔的形狀或夾形狀。爲此 我不得不穀歌地圖的路徑轉換爲WKT和我寫此Javascript:
function doeWKT(dePaths) {
var deWKTarray = [];
for (var i = 0; i < dePaths.length; i++) {
dePath = dePaths.getArray()[i].getArray();
var deKomma = "";
var deCoords = "";
for (var j = 0; j < dePath.length; j++) {
deLatLng = dePath[j];
if (j == 0) var deCoords0 = deKomma + deLatLng.lng().toFixed(6) + " " + deLatLng.lat().toFixed(6);
deCoords += deKomma + deLatLng.lng().toFixed(6) + " " + deLatLng.lat().toFixed(6);
deKomma = ",";
}
deWKTarray.push("(" + deCoords + "," + deCoords0 + ")");
}
var deHoles = [];
var deReader = new jsts.io.WKTReader();
for (var i = 0; i < deWKTarray.length; i++) {
var deHole = deReader.read("POLYGON("+deWKTarray[i]+")");
if (!deHoles[i]) deHoles[i] = -1;
for (var j =0; j < deWKTarray.length; j++) {
if (i != j) {
var deContainer = deReader.read("POLYGON(" + deWKTarray[j] + ")");
if (deHole.within(deContainer)) deHoles[i] = j;
}
}
}
var deKomma = "";
var deWKTstring = "";
var deMulti = false;
for (var i = 0; i < deWKTarray.length; i++) {
if (deHoles[i] == -1) {
deWKTstring += deKomma + "(" + deWKTarray[i] + "";
if (i > 0) var deMulti = true;
}
for (var j = 0; j < deHoles.length; j++) {
if (deHoles[j] == i) deWKTstring += "," + deWKTarray[j] + "";
}
if (deHoles[i] == -1) deWKTstring += ")";
deKomma = ",";
}
if (deMulti) deWKTstring = "MULTIPOLYGON(" + deWKTstring +")";
else deWKTstring = "POLYGON" + deWKTstring;
return deWKTstring;
}
你可以試試/看到寄託都在http://maps.amsterdam.nl/testshape/beheer工作(讀圖例說明)
我會使用一個lib對於這對夫婦是 http://gis.stackexchange.com/questions/7159/pure-javascript-library-for-geometry-operations – 2013-02-24 15:34:44