White globe when zoomed out

I have my Earth file set up to process WMS imagery data similarly to the nexrad example. I am getting terrain but for some reason when I zoom back out my globe turns white. Why is my terrain disappearing when I zoom out ?

Hi jeladi

It may be that the WMS image layer you configured has no data at the first several levels.

Hi jeladi

How to solve this problem? I think there are two ways.

1.Set the first_lod of the terrain to avoid loading no data levels. first need to add a debug layer, and get the wms layer min level.

   SXEarth is a osgEarth GUI editor, demonstrate the figure.
   

2.Add a new image layer and configure max level as the wms layer max no data level.

   Demo figure
   
   
  To achieve smooth transition of the two layers, you can use the min_range property of world.tif layer, terrain's attenuation_distance property is also effect. You can try it.