openlayers 多边形重叠判断平移
2014-05-06 19:57
363 查看
主要目的：
在做GIS开发时，常常需要用到空间判断的算法。比如：判断地图中的多边形与多边形是否相交。我在项目中具体的需求就是如此，在绘制多个polygon多边形后，判断多边形之间是否重叠，如果重叠，则需要将两个多边形分离。延某一个方向移动该多边形。在选择分离重叠的多边形方案时，可以确定以其中一个多边形为中心，即参考物。移动时平移其周边的多边形即可。1，首先要获得周边移动对象
2，判断多边形之间是否相交，用自带函数intersect()
3，计算移动的方向和移动距离，由于openalyers中的move(x,y)和moveto(x,y)，如果直接将x,y代入数字只能移动一段特定的距离，没有方向的选择，所以我们这里还是用move(x,y)函数，但是首先获得需要一定方向和距离直线上两点的经纬度，然后利用getViewPortPxFromLonLat(lonlat, resolution) 函数将具体的经纬度坐标转换为像素点。
调用dragfeature类中的geometry.move(res * (pixel.x - lastPixel.x),
res * (lastPixel.y - pixel.y));函数。便可移动多边形，方向和距离分别为两点经纬度的方向和距离。
代码显示：
1判断多边形重叠：var res = map.getResolution();
for(var i=0;i<response['profile'].length;i++){
var feat_be = response['profile'][i].belongsSegment;
var k =i%2;
var f = 0;
if(k==0){
f = i;
}else if(k==1){
f = i-1;
}
var a = feat[f].geometry.getVertices()[1];
var b = feat[f].geometry.getVertices()[0];
var pixel = getViewPortPxFromLonLat(a , res);
var lastPixel = getViewPortPxFromLonLat(b , res);
intersects12 = feat[i].geometry.intersects(feat_survery.geometry);
var j =i+1;
/*
* 判断剖面和测绘是否相交
*/
while(intersects12) {
if(j<response['profile'].length){
feat[i].geometry.move(res * (pixel.x - lastPixel.x),
res * (lastPixel.y - pixel.y));
feat[j].geometry.move(res * (pixel.x - lastPixel.x),
res * (lastPixel.y - pixel.y));
for(var ho=0;ho<response['hole'].length;ho++){
var hole_be = response['hole'][ho].belongsSegment;
if(feat_be == hole_be){
hole[ho].geometry.move(res * (pixel.x - lastPixel.x),
res * (lastPixel.y - pixel.y));
layer.drawFeature(hole);
}
}
for(var ca=0;ca<response['cable'].length;ca++){
var cable_be = response['cable'][ca].belongsSegment;
if(feat_be == cable_be){
cable[ca].geometry.move(res * (pixel.x - lastPixel.x),
res * (lastPixel.y - pixel.y));
layer.drawFeature(cable);
}
}
layer.drawFeature(feat);
layer.drawFeature(hole);
layer.drawFeature(cable);
}
intersects12 = feat[i].geometry.intersects(feat_survery.geometry);
}
}2，经纬度转换为像素点：/*
* 函数：经纬度转换为像素点
*/
function getViewPortPxFromLonLat(lonlat, resolution) {
var px = null;
if (lonlat != null) {
px = new OpenLayers.Pixel(
(1/resolution * (lonlat.x - extent.left)),
(1/resolution * (extent.top - lonlat.y))
);
}
return px;
}具体代码为我实际项目中应用代码：
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<%@ taglib prefix="s" uri="/struts-tags" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html;charset=UTF-8" />
<%
String path = request.getContextPath();
String basePath = request.getScheme() + "://"
+ request.getServerName() + ":" + request.getServerPort()
+ path + "/";
String id = request.getParameter("id");
%>
<base href="<%=basePath%>">
<link href="style/profile.css" rel="stylesheet" type="text/css" media="screen"/>
</head>
<body onload='init(<%=id%>)'>
<div id="map"></div>
<script>
function init(id){
var extent = new OpenLayers.Bounds(//初始化视图的边界设置,参照conf.cdi文件中的值
120.50490375617102, 30.588471912865483,
120.5859733795086, 30.685245907613851
);
var map = new OpenLayers.Map('map');
map.div.oncontextmenu = function () { return false;};//屏蔽浏览器的右键菜单
var baseLayer = new OpenLayers.Layer.Image(
'Grid',
'img/blank.png',
extent,
new OpenLayers.Size(2000, 1500),
{
isBaseLayer: true,
numZoomLevels: 8
});
var layer = new OpenLayers.Layer.Vector();
map.addLayers([baseLayer,layer]);
var mousePositionCtl = new OpenLayers.Control.MousePosition({
prefix: '<a target="_blank" ' +
'href="http://spatialreference.org/ref/epsg/4326/">' +
'EPSG:4326</a> coordinates: ',
separator: ' | ',
numDigits: 2,
emptyString: 'Mouse is not over map.'
}
);
map.addControl(mousePositionCtl);
OpenLayers.Request.GET({
url: "getProfileCableHoleByWell.action?WellId="+id,
success: profileProperty_success
});
function profileProperty_success(req){
var format = new OpenLayers.Format.JSON();
var response = format.read(req.responseXML || req.responseText);
var wellStyle;
if(response['well'].countSquare && parseInt(response['well'].countSquare)!=0){
wellStyle = {
externalGraphic : "img/icons/square.svg",
pointRadius : 8
}
}else{
wellStyle = {
externalGraphic : "img/icons/well.svg",
pointRadius : 8
};
}
var style;
var features = [];
var index = 0;
var segment = [], feat = [], hole = [], cable = [];
var feat_survery, intersects12;
console.log(response)
for(key in response){
if(key != 'well'){
for(var i=0;i<response[key].length;i++,index++){
switch(key){
case 'ccable':
var cableRadius = 6;
switch(response[key][i].voltagegrade){
case 0:
style = {externalGraphic:"img/holes/communicate.svg",pointRadius: cableRadius};
break;
case 1:
style = {externalGraphic:"img/holes/hole04.svg",pointRadius: cableRadius};
break;
case 2:
style = {externalGraphic:"img/holes/hole10.svg",pointRadius: cableRadius};
break;
case 3:
style = {externalGraphic:"img/holes/hole35.svg",pointRadius: cableRadius};
break;
case 4:
style = {externalGraphic:"img/holes/hole110.svg",pointRadius: cableRadius};
break;
case 5:
style = {externalGraphic:"img/holes/hole220.svg",pointRadius: cableRadius};
break;
case 6:
style = {externalGraphic:"img/holes/hole330.svg",pointRadius: cableRadius};
break;
case 7:
style = {externalGraphic:"img/holes/hole500.svg",pointRadius: cableRadius};
break;
case 8:
style = {externalGraphic:"img/holes/hole750.svg",pointRadius: cableRadius};
break;
}
break;
case 'segment':
switch(response[key][i].objecttype){
case 1020211:
style = {
strokeWidth : 10,
strokeColor : '#3399CC'
};// 排管
break;
case 1020212:
style = {
strokeWidth : 10,
strokeColor : '#00FFFF'
};// 桥架
break;
case 1020213:
style = {
strokeWidth : 10,
strokeColor : '#996600'
};// 沟道
break;
case 1020214:
style = {
strokeWidth : 10,
strokeColor : '#00FF00'
};// 直埋
break;
case 1020215:
style = {
strokeWidth : 10,
strokeColor : '#666666'
};// 隧道
break;
case 1020216:
style = {
strokeWidth : 10,
strokeColor : '#003399'
};// 顶管
break;
case 1020203:
style = {
strokeOpacity: 0.5,
strokeWidth : 10,
strokeColor : '#3399CC'
};// 虚拟管沟
break;
}
break;
case 'pointsurvery':
style = {
strokeColor : "black",
strokeOpacity : 0,
strokeWidth : 1,
fillOpacity : 0,
fillColor : "#4FD5D6",
pointRadius : 6,
cursor : "inherit"
};//工井测绘
break;
case 'profile':
style = {
strokeColor : "black",
strokeOpacity : 0,
strokeWidth : 1,
fillOpacity : 0,
fillColor : "#FFCC00",
pointRadius : 6,
cursor : "inherit"
};
break;
default:
style = {
strokeColor : "none",
strokeOpacity : 1,
strokeWidth : 1,
fillOpacity : 0.9,
fillColor : "none",
pointRadius : 6,
cursor : "inherit"
};
}
features[index] = new OpenLayers.Feature.Vector(
new OpenLayers.Geometry.fromWKT(response[key][i].geometry),null,style
);
}
}
}
/*
* 剖面弹出框设备样式
*/
style_profile = {
strokeColor : "black",
strokeOpacity : 1,
strokeWidth : 1,
fillOpacity : 0.5,
fillColor : "#FFCC00",
pointRadius : 6,
cursor : "inherit"
};
style_pointsurvery = {
strokeColor : "black",
strokeOpacity : 1,
strokeWidth : 1,
fillOpacity : 0.5,
fillColor : "#4FD5D6",
pointRadius : 6,
cursor : "inherit"
};
style_segment = {
strokeColor : "red",
strokeOpacity : 1,
strokeWidth : 4,
strokeDashstyle : 'dash',
cursor : "inherit"
};
style_hole = {
strokeColor : "black",
strokeOpacity : 1,
strokeWidth : 1,
fillColor : "white",
cursor : "inherit"
};
features[features.length] = new OpenLayers.Feature.Vector(new OpenLayers.Geometry.fromWKT(response['well'].geometry),null,wellStyle);
layer.addFeatures(features);
if(response['profile'].length > 0 ){
for(var i=0;i<response['profile'].length;i++){
feat[i] = new OpenLayers.Feature.Vector( new OpenLayers.Geometry.fromWKT(response['profile'][i].geometry),null,style_profile);
}
layer.addFeatures(feat);
}
if(response['hole'].length > 0){
for(var ho=0;ho<response['hole'].length;ho++){
hole[ho] = new OpenLayers.Feature.Vector( new OpenLayers.Geometry.fromWKT(response['hole'][ho].geometry),null,style_hole);
}
layer.addFeatures(hole);
}
if(response['cable'].length > 0){
var cableRadius = 6;
for(var ca=0;ca<response['cable'].length;ca++){
switch(response['cable'][ca].voltagegrade){
case 0:
style_cable = {externalGraphic:"img/holes/communicate.svg",pointRadius: cableRadius};
break;
case 1:
style_cable = {externalGraphic:"img/holes/hole04.svg",pointRadius: cableRadius};
break;
case 2:
style_cable = {externalGraphic:"img/holes/hole10.svg",pointRadius: cableRadius};
break;
case 3:
style_cable = {externalGraphic:"img/holes/hole35.svg",pointRadius: cableRadius};
break;
case 4:
style_cable = {externalGraphic:"img/holes/hole110.svg",pointRadius: cableRadius};
break;
case 5:
style_cable = {externalGraphic:"img/holes/hole220.svg",pointRadius: cableRadius};
break;
case 6:
style_cable = {externalGraphic:"img/holes/hole330.svg",pointRadius: cableRadius};
break;
case 7:
style_cable = {externalGraphic:"img/holes/hole500.svg",pointRadius: cableRadius};
break;
case 8:
style_cable = {externalGraphic:"img/holes/hole750.svg",pointRadius: cableRadius};
break;
}
cable[ca] = new OpenLayers.Feature.Vector( new OpenLayers.Geometry.fromWKT(response['cable'][ca].geometry),null,style_cable);
}
layer.addFeatures(cable);
}
if(response['segment'].length > 0 ){
for(var se=0;se<response['segment'].length;se++){
segment[se] = new OpenLayers.Feature.Vector( new OpenLayers.Geometry.fromWKT(response['segment'][se].geometry),null,style_segment);
}
layer.addFeatures(segment);
}
if(response['pointsurvery'].length > 0 ){
feat_survery = new OpenLayers.Feature.Vector( new OpenLayers.Geometry.fromWKT(response['pointsurvery'][0].geometry),null,style_pointsurvery);
layer.addFeatures(feat_survery);
if(response['profile'].length>0){
var res = map.getResolution();
for(var i=0;i<response['profile'].length;i++){
var feat_be = response['profile'][i].belongsSegment;
var k =i%2;
var f = 0;
if(k==0){
f = i;
}else if(k==1){
f = i-1;
}
var a = feat[f].geometry.getVertices()[1];
var b = feat[f].geometry.getVertices()[0];
var pixel = getViewPortPxFromLonLat(a , res);
var lastPixel = getViewPortPxFromLonLat(b , res);
intersects12 = feat[i].geometry.intersects(feat_survery.geometry);
var j =i+1;
/*
* 判断剖面和测绘是否相交
*/
while(intersects12) {
if(j<response['profile'].length){
feat[i].geometry.move(res * (pixel.x - lastPixel.x),
res * (lastPixel.y - pixel.y));
feat[j].geometry.move(res * (pixel.x - lastPixel.x),
res * (lastPixel.y - pixel.y));
for(var ho=0;ho<response['hole'].length;ho++){
var hole_be = response['hole'][ho].belongsSegment;
if(feat_be == hole_be){
hole[ho].geometry.move(res * (pixel.x - lastPixel.x),
res * (lastPixel.y - pixel.y));
layer.drawFeature(hole);
}
}
for(var ca=0;ca<response['cable'].length;ca++){
var cable_be = response['cable'][ca].belongsSegment;
if(feat_be == cable_be){
cable[ca].geometry.move(res * (pixel.x - lastPixel.x),
res * (lastPixel.y - pixel.y));
layer.drawFeature(cable);
}
}
layer.drawFeature(feat);
layer.drawFeature(hole);
layer.drawFeature(cable);
}
intersects12 = feat[i].geometry.intersects(feat_survery.geometry);
}
}
/* * 函数：经纬度转换为像素点 */ function getViewPortPxFromLonLat(lonlat, resolution) { var px = null; if (lonlat != null) { px = new OpenLayers.Pixel( (1/resolution * (lonlat.x - extent.left)), (1/resolution * (extent.top - lonlat.y)) ); } return px; }
}
}
map.zoomToExtent(extent, true);
var center = new OpenLayers.LonLat(features[features.length-1].geometry.x, features[features.length-1].geometry.y).transform(
new OpenLayers.Projection("EPSG:4326"),
map.getProjectionObject());
map.setCenter(center,5);
console.log(map)
}
}
</script>
<script src="lib/OpenLayers.js"></script>
</body>
</html>
内容来自用户分享和网络整理，不保证内容的准确性，如有侵权内容，可联系管理员处理 
相关文章推荐
- PostGis 如何判断两个多边形是否有重叠的区域
- 判断多边形与多边形是否相交的方法，代码来自于OpenLayers。
- 判断多边形与多边形是否相交的方法，代码来自于OpenLayers。
- pku 1584 A Round Peg in a Ground Hole 计算几何——凸多边形判断+点在多边形内判断+求点到直线距离
- HDU3902 判断简单多边形是否对称
- ［几何］判断点是否在不规则多边形内
- *寒假水76——Shape of HDU 【判断凹凸多边形问题】
- 判断鼠标在 多边形外
- 几种判断点与多边形关系的算法介绍
- 判断点是否在任意多边形内（java）
- 判断一个点是否在多边形内部
- 点在多边形内算法——判断一个点是否在一个复杂多边形的内部翻译 (转)
- 【算法】判断点在多边形内部
- POJ 1410 判断线段相交点在多边形内外
- 空间多边形顺逆时针的判断
- 内存块重叠的判断方法
- 判断两段时间是否有重叠部分
- 判断一个点是否在多边形内部 [3] 回转数法
- LightOJ1190->判断一个点是不是在一个任意多边形内
- 判断点是否在多边形内的算法和C语言程序