kml - KML文件渲染问题-平滑文本

Question

我们有一些KML文件，其中包含一些定义非常严格的折线（主要用于绘制文本，但并非唯一）。当我们将相同的KML文件提取到Cesium（1.6或1.7），OpenLayers或GoogleEarth中时，得到的结果是相同的：


铯以非常锯齿的方式呈现文本。
OpenLayers和GoogleEarth均可流畅地呈现文本。







我们研究了我们认为负责数据“精简”的removeDuplicates()方法。如果我们将EPSILON设置为较高的值，则“文本折线”会很好地呈现。我们可以在某处覆盖removeDuplicatesEpsilon变量吗？

在removeDuplicates()方法内部，一旦确定要删除至少1个点，就可以将每个后续点与列表中的上一个点进行比较。它不应该将每个点与以前接受的点进行比较吗？ （与列表中的上一个点相对，后者也可能不包括在内）。

铯代码：

var removeDuplicatesEpsilon = CesiumMath.EPSILON7;

PolylinePipeline.removeDuplicates = function(positions) {
    if (!defined(positions)) {
           throw new DeveloperError('positions is required.');
    }

     var length = positions.length;
     if (length < 2) {
          return undefined;
     }

     var i;
     var v0;
     var v1;

     for (i = 1; i < length; ++i) {
          v0 = positions[i - 1];
          v1 = positions[i];
          if (Cartesian3.equalsEpsilon(v0, v1, removeDuplicatesEpsilon)) {
               break;
          }
     }

     if (i === length) {
          return undefined;
     }

     var cleanedPositions = positions.slice(0, i);
     for (; i < length; ++i) {
          v0 = positions[i - 1];
          v1 = positions[i];
          if (!Cartesian3.equalsEpsilon(v0, v1, removeDuplicatesEpsilon)) {
               cleanedPositions.push(Cartesian3.clone(v1));
          }
     }

     return cleanedPositions;
};

样本KML-

<?xml version="1.0" encoding="utf-16"?>
<kml xmlns="http://www.opengis.net/kml/2.2">
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    <name>Letters</name>
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Answer 1

这确实是Cesium中的错误。我已经打开pull request #2609进行修复。