Rendering polygons under globe?

I have no experience in Cesium. As I was playing around with it to evaluate if it fits our needs I encountered two issues:

- The first issue we encounter is that as we try to display primitives underground (such as a RectanglePrimitive with a negative height), they stop being rendered if the view angle strays too far from overhead.
This issue doesn't occur if we set to false.

- Additionally, if we do
var widget = new Cesium.CesiumWidget('cesiumContainer');
widget.scene.imageryLayers.get(0).alpha = 0.1;
Then instead of having the space background being visible behind the layer, we see the uniformly blue globe. Is there a way to set it as to be transparent?



We haven’t added full support for subsurface visualization but here are some potential workarounds.

For the RectanglePrimitive, you are probably running into a culling issues. To try to work around it, in Primitive.js, set the cull property of all DrawCommand instances to false to disable culling.

For a fully transparent globe, you may be to change initialColor in GlobeFS.glsl to include an alpha value and enable blending in the render states in Globe.js.




I've tried disabling culling but to no effect

( adding several lines like this, yes?

   foo = new DrawCommand();
   foo.cull = {enabled : false};


The rest is fine! Setting the initialColor to black in the shader got me the effect I wanted.

Thanks for your help.


foo.cull = false;


FYI, we just added a Globe.baseColor property to allow for setting of the color of the globe for areas without imagery. It will be available in the 1.2 release on October 1st. See this pull request for details: