Kml - MultiGeometry with Polygons

Our application has a drawing tool that allows the user to define a portion of a dome(half sphere). The user defines a beginning angle, ending angle and a radius ( ex. 1, 180, 800000 see attached pic ). The object is generated in kml and then loaded into cesium. In cesium there are triangles left out(see pic). In GE, it looks like the polygons are defining quads not triangles so that is why the kml renders differently.

Is there away to fix this the issue in the kml? Do I need to define the missing triangle? or is there a way to specify a quad as apposed to triangles?

Is there a better way to do this in CZML? Or would the czml solution define this object in the same manner?



2_1450116435.kml (58.9 KB)

Hello Scott,

This is happening because our polygons don’t support being drawn perpendicular to the surface. I’m surprised the outer shell of the sphere triangulated so well- the polygons must be at just enough of an angle.

I think you could use an extruded LineString for the front face instead. This would create a WallGeometry behind the scenes, which is designed for drawing perpendicular to the globe.



Ultimately, we should probably handle this case in Cesium too, so I added an item to the KML roadmap issue.

Hi Scott. we finally had a chance to fix this issue and the fix will be included in Cesium 1.48 release on August 1st.