imagery_layers pull request

Hey folks,

I just submitted a pull request for the “imagery_layers” branch:

From the pull request:

Adds the ability to layer imagery from multiple sources and adjust the alpha of each independently. It also has a new architecture for rendering the surface of the globe that is a big step toward rendering terrain. For starters, check out the two new Sandcastle apps: “Imagery Layers” and “Map Projections”.

Most of the action happens (or at least starts) in CentralBodySurface.js. If you want to understand how it works, the (four line) update function is the place to start.

There is no shortage of additional things that could be done, but I think this is a significant improvement from master and is worthy of a review.

This branch represents 379 commits over 3 months. If you have some time to take a look at the code and provide us feedback, Scott and I would really appreciate it. Once everyone has had a chance to review and the code has been updated based on the feedback, we’ll merge the pull request and the imagery layers functionality will be available in master.



The “imagery layers” branch has been merged in master! Please let me know if you see any problems or have any questions.

I’ll be updating the Features page ( and the Roadmap ( today.

We also need an In-Depth Guide ( for imagery, though I’m not sure how soon I’ll get to that.

Thanks to everyone who reviewed the pull request, and also to everyone who tried the branch as it was in development and sent bug reports and other feedback.