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Create equirectangular/sphere projection map


Question

I have what is apparently called an equirectangular projection of the world. I can use the 3D functionality of Photoshop to use this as a texture for a globe, by creating a sphere mesh; or I can use "CC Sphere" in After Effects etc. This is great.

I now want to attach (flat) objects to the surface of that sphere (imagine some sort of sticker, an image frame, or text. Clearly, I cannot just add them to the original 2d-projection of the earth. They need to fit the projection. This is very effectually visualized here:

http://forums.cgsociety.org/showpost.php?p=6954169&postcount=8

I have no idea how to approach this, or what tools to even use. I figure it might be necessary to design this in 3D to begin with, and then export it to a texture. Any ideas?

2014/01/14
1
5
1/14/2014 10:28:00 PM

The issue with the equirectangular map is the Tissot Indicatrix, which is the way the lines spread out towards the top and bottom of the map (the distortion when wrapping and unwrapping the texture on a shape). See:

  1. Tissot's indicatrix
  2. How does one calculate distortion on Equirectangular Projection?
  3. Equirectangular projection
  4. USGS Publications Warehouse Map Projections
  5. PANORAMIC IMAGE PROJECTIONS
  6. PanoToolsNG
  7. Panorama photo stitcher

I'm still working on trying to create an action or a set of actions that work with distorting maps to projection. I'll post something once I get it working.

2017/04/13
3
4/13/2017 12:33:00 PM