我的工作的OpenLayers，有一个问题，当我尝试横跨国际日期变更线多次在地图上添加一个线串。
要显示在连续区间我添加了一个功能HandleDateline()返回我修改跨越两个世界的线串（移位要么向左或向右世界）坐标。
然而，当你放大左侧世界目前入驻查看线串消失。此外，如果你尝试将地图移动到左，行云之遥。
奇怪的是，如果该线横跨1倍以上，线串上左边的世界消失了，否则会发生相同的右世界。也观察到，取出datelinecrossing[]无论是前3个或最后一个3分，我将张贴了下来。
我期待连续线串穿越国际日期变更线没有像消失的任何问题。
如果有这更好的办法，我向所有人开放的思想。这里是斌：ol dateline problem
你必须拆分编程穿越国际日期变更线在日界线线。
var points = [
[-170, -10],
[170, 0],
[-170, 10]
];
var vectorSource = new ol.source.Vector();
vectorSource.addFeature(createFeature(points));
var vectorLayer = new ol.layer.Vector({
source: vectorSource,
style: new ol.style.Style({
stroke: new ol.style.Stroke({
width: 2,
color: "red"
})
})
});
var osmLayer = new ol.layer.Tile({
source: new ol.source.OSM()
});
var map = new ol.Map({
layers: [osmLayer, vectorLayer],
target: document.getElementById("map"),
view: new ol.View({
center: ol.proj.transform([180, 0], "EPSG:4326", "EPSG:3857"),
zoom: 3
})
});
var graticule = new ol.Graticule({
strokeStyle: new ol.style.Stroke({
color: "rgba(255,120,0,0.9)",
width: 1.5,
lineDash: [0.5, 4]
}),
showLabels: true
});
graticule.setMap(map);
// -------------------------------------------------
function createFeature(points) {
var pointsSplitted = [];
var pointsArray = [];
pointsSplitted.push(points[0]);
var lastLambda = points[0][0];
for (var i = 1; i < points.length; i++) {
var lastPoint = points[i - 1];
var nextPoint = points[i];
if (Math.abs(nextPoint[0] - lastLambda) > 180) {
var deltaX = xToValueRange(nextPoint[0] - lastPoint[0]);
var deltaY = nextPoint[1] - lastPoint[1];
var deltaXS = xToValueRange(180 - nextPoint[0]);
var deltaYS;
if (deltaX === 0) {
deltaYS = 0;
} else {
deltaYS = deltaY / deltaX * deltaXS;
}
var sign = lastPoint[0] < 0 ? -1 : 1;
pointsSplitted.push([180 * sign, nextPoint[1] + deltaYS]);
pointsArray.push(pointsSplitted);
pointsSplitted = [];
pointsSplitted.push([-180 * sign, nextPoint[1] + deltaYS]);
}
pointsSplitted.push(nextPoint);
lastLambda = nextPoint[0];
}
pointsArray.push(pointsSplitted);
var geom = new ol.geom.MultiLineString(pointsArray);
geom.transform("EPSG:4326", "EPSG:3857");
var feature = new ol.Feature({
geometry: geom
});
return feature;
}
function xToValueRange(x) {
if (Math.abs(x) > 180) {
var sign = x < 0 ? -1 : 1;
return x - 2 * 180 * sign;
} else {
return x;
}
}html,
body,
#map {
width: 100%;
height: 100%;
overflow: hidden
}<link href="https://cdn.rawgit.com/openlayers/openlayers.github.io/master/en/v5.3.0/css/ol.css" rel="stylesheet" />
<script src="https://cdn.rawgit.com/openlayers/openlayers.github.io/master/en/v5.3.0/build/ol.js"></script>
<body>
<div id="map" class="map" tabindex="0"></div>
</body>简化HandleDateline因此所有坐标无论是在正常的世界或左世东部的西部似乎解决它（所以如果几何跨越日期变更线的程度在左侧世界开始）
function HandleDateline(array) {
for (var i = 0; i < array.length ; i++) {
if (array[i][0] > 0) {
array[i][0] -= 360;
}
}
}
然而，在世界向右西部国际日期变更线的点出现在屏幕下方的线串被渲染，而日界线东侧的那些都是在它上面。移动HandleDateline(datelinecrossing);以上datelinecrossing.forEach修复。
您可能还需要（除非你需要他们单独选择），以考虑使用点多点的几何形状。
HandleDateline(datelinecrossing);
var pdlcrossing = new ol.Feature({
geometry: new ol.geom.MultiPoint(datelinecrossing).transform('EPSG:4326', 'EPSG:3857')
});
drawingSource.addFeature(pdlcrossing);
var dlcrossing = new ol.Feature({
geometry: new ol.geom.LineString(datelinecrossing).transform('EPSG:4326', 'EPSG:3857')
});
drawingSource.addFeature(dlcrossing);
还有在右边的世界国际日期变更线以西缩放一个问题，所以我觉得有需要两套各几何，一个向左偏移，另一个360度以下权利：
function PlotGeometries(datelinecrossing){
var pgeom = new ol.geom.MultiPoint(datelinecrossing);
var pdlcrossing = new ol.Feature({
geometry: pgeom.clone().transform('EPSG:4326', 'EPSG:3857')
});
drawingSource.addFeature(pdlcrossing);
pgeom.translate(360,0);
var pdlcrossing2 = new ol.Feature({
geometry: pgeom.transform('EPSG:4326', 'EPSG:3857')
});
drawingSource.addFeature(pdlcrossing2);
var geom = new ol.geom.LineString(datelinecrossing);
var dlcrossing = new ol.Feature({
geometry: geom.clone().transform('EPSG:4326', 'EPSG:3857')
});
drawingSource.addFeature(dlcrossing);
geom.translate(360,0);
var dlcrossing2 = new ol.Feature({
geometry: geom.transform('EPSG:4326', 'EPSG:3857')
});
drawingSource.addFeature(dlcrossing2);
}
刚刚成立的程度，为你的工作世界的一部分地图视图。