Merge pull request #7533 from AnalyticalGraphicsInc/fixPolygonRectang…

…leIdl base polygon geometry rectangle IDL handling on Rectangle.fromCartesianArray
CesiumGS · Feb 5, 2019 · 44c5a17 · 44c5a17
2 parents 998cf0a + d65bf8e
commit 44c5a17
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Showing 3 changed files with 44 additions and 10 deletions.
diff --git a/CHANGES.md b/CHANGES.md
@@ -12,6 +12,7 @@ Change Log
 ##### Fixes :wrench:
 * Fixed an issue where models would cause a crash on load if some primitives were Draco encoded and others were not. [#7383](https://github.com/AnalyticalGraphicsInc/cesium/issues/7383)
 * Fixed Node.js support for the `Resource` class and any functionality using it internally.
+* Fixed an issue where some ground polygons crossing the Prime Meridian would have incorrect bounding rectangles. [#7533](https://github.com/AnalyticalGraphicsInc/cesium/pull/7533)
 
 ### 1.54 - 2019-02-01
 

diff --git a/Source/Core/PolygonGeometry.js b/Source/Core/PolygonGeometry.js
@@ -379,8 +379,8 @@ define([
     var startCartographicScratch = new Cartographic();
     var endCartographicScratch = new Cartographic();
     var idlCross = {
-        west : 0.0,
-        east : 0.0
+        westOverIDL : 0.0,
+        eastOverIDL : 0.0
     };
     var ellipsoidGeodesic = new EllipsoidGeodesic();
     function computeRectangle(positions, ellipsoid, arcType, granularity, result) {
@@ -406,8 +406,8 @@ define([
         result.south = Number.POSITIVE_INFINITY;
         result.north = Number.NEGATIVE_INFINITY;
 
-        idlCross.west = Number.POSITIVE_INFINITY;
-        idlCross.east = Number.NEGATIVE_INFINITY;
+        idlCross.westOverIDL = Number.POSITIVE_INFINITY;
+        idlCross.eastOverIDL = Number.NEGATIVE_INFINITY;
 
         var inverseChordLength = 1.0 / CesiumMath.chordLength(granularity, ellipsoid.maximumRadius);
         var positionsLength = positions.length;
@@ -429,9 +429,16 @@ define([
         ellipsoidGeodesic.setEndPoints(startCartographic, endCartographic);
         interpolateAndGrowRectangle(ellipsoidGeodesic, inverseChordLength, result, idlCross);
 
-        if (result.east - result.west > idlCross.west - idlCross.east) {
-            result.east = idlCross.east;
-            result.west = idlCross.west;
+        if (result.east - result.west > idlCross.eastOverIDL - idlCross.westOverIDL) {
+            result.west = idlCross.westOverIDL;
+            result.east = idlCross.eastOverIDL;
+
+            if (result.east > CesiumMath.PI) {
+                result.east = result.east - CesiumMath.TWO_PI;
+            }
+            if (result.west > CesiumMath.PI) {
+                result.west = result.west - CesiumMath.TWO_PI;
+            }
         }
 
         return result;
@@ -456,8 +463,9 @@ define([
             result.south = Math.min(result.south, latitude);
             result.north = Math.max(result.north, latitude);
 
-            idlCross.west = longitude > 0.0 ? Math.min(longitude, idlCross.west) : idlCross.west;
-            idlCross.east = longitude < 0.0 ? Math.max(longitude, idlCross.east) : idlCross.east;
+            var lonAdjusted = longitude >= 0 ?  longitude : longitude +  CesiumMath.TWO_PI;
+            idlCross.westOverIDL = Math.min(idlCross.westOverIDL, lonAdjusted);
+            idlCross.eastOverIDL = Math.max(idlCross.eastOverIDL, lonAdjusted);
         }
     }
 

diff --git a/Specs/Core/PolygonGeometrySpec.js b/Specs/Core/PolygonGeometrySpec.js
@@ -4,6 +4,7 @@ defineSuite([
         'Core/arrayFill',
         'Core/BoundingSphere',
         'Core/Cartesian3',
+        'Core/Cartographic',
         'Core/Ellipsoid',
         'Core/GeometryOffsetAttribute',
         'Core/GeometryPipeline',
@@ -17,6 +18,7 @@ defineSuite([
         arrayFill,
         BoundingSphere,
         Cartesian3,
+        Cartographic,
         Ellipsoid,
         GeometryOffsetAttribute,
         GeometryPipeline,
@@ -1095,7 +1097,7 @@ defineSuite([
         expect(CesiumMath.toDegrees(boundingRhumb.west)).toEqualEpsilon(-90.0, CesiumMath.EPSILON10);
     });
 
-    it('computes rectangles that cross the IDL', function() {
+    it('computes rectangles for rhumbline polygons that cross the IDL', function() {
         var pRhumb = new PolygonGeometry({
             vertexFormat : VertexFormat.POSITION_AND_ST,
             polygonHierarchy: {
@@ -1116,6 +1118,29 @@ defineSuite([
         expect(CesiumMath.toDegrees(boundingRhumb.west)).toEqualEpsilon(175.0, CesiumMath.EPSILON10);
     });
 
+    it('computes rectangles for geodesic polygons that cross the IDL', function() {
+        var minLon = Cartographic.fromDegrees(-178, 3);
+        var minLat = Cartographic.fromDegrees(-179, -4);
+        var maxLon = Cartographic.fromDegrees(178, 3);
+        var maxLat = Cartographic.fromDegrees(179, 4);
+        var cartesianArray = Ellipsoid.WGS84.cartographicArrayToCartesianArray([minLat, minLon, maxLat, maxLon]);
+
+        var pGeodesic = new PolygonGeometry({
+            vertexFormat : VertexFormat.POSITION_AND_ST,
+            polygonHierarchy: {
+                positions : cartesianArray
+            },
+            granularity: CesiumMath.RADIANS_PER_DEGREE,
+            arcType : ArcType.GEODESIC
+        });
+
+        var boundingGeodesic = pGeodesic.rectangle;
+        expect(boundingGeodesic.east).toEqualEpsilon(minLon.longitude, CesiumMath.EPSILON10);
+        expect(boundingGeodesic.south).toEqualEpsilon(minLat.latitude, CesiumMath.EPSILON10);
+        expect(boundingGeodesic.west).toEqualEpsilon(maxLon.longitude, CesiumMath.EPSILON10);
+        expect(boundingGeodesic.north).toEqualEpsilon(maxLat.latitude, CesiumMath.EPSILON10);
+    });
+
     it('computeRectangle', function() {
         var options = {
             vertexFormat : VertexFormat.POSITION_AND_ST,