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Thread: Rotate a raster on a globe?

  1. #1

    Question Rotate a raster on a globe?

    Hiya,
    I need to get a rectangular projection to project from a different angle. I've put my main landmasses on the poles, so the ocean takes up most of the central space on my projections and the landmasses are mostly warped. I've got access to gplates, gprojector, and photoshop. I'm willing to download any other free program (I'd like to avoid blender though). Does anyone know how to make a mesh/texture rotate on a sphere in these programs, or just make it project with the equator instead of a meridian at the top and bottom of the map?

  2. #2
    Guild Grand Master Azélor's Avatar
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    I'm going to repost my reply from the other day. Not sure if you did notice it.

    You can do that with g.projector. Use either the azimuthal equidistant or orthographic projections centered on the pole to create one map for each pole.


    Like this : Click image for larger version. 

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  3. #3
    Administrator waldronate's Avatar
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    I think that he wants a generalized equirectangular projection to allow spinning the globe under the projection (if that makes any sense). The Cassini projection is the transverse of the Plate Carree projection, but I think that he wants a generalized one. My brain won't spit out the name of that one right now, though, so I'm not much use on that front.

    While he certainly can convert his equirectangular input to something like Orthographic, move the center of projection to move the poles, and then unproject back to Equirectangular, there will likely be some unpleasant distortions in the process that will require high resolution images to reduce the error. He should be able to do all of that using something like gdalwarp, but that seems hard...

  4. #4
    Professional Artist Naima's Avatar
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    To put it simplier , he wants to pass froman Equidistant rectangular projection... to a polar a Polar equirectangular projection,
    basically he wants to put the pole in center of his rectangular map ... am I right?

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