Converting a planar map to spherical

This is more for curiosity than anything. I have a map which was developed as a planar map. I am in the process of bringing it into FT3+ using simple create. However, while the shape of the continents is preserved, the east-west distances obviously are not.

Currently the main continent ranges from latitude 86.5 degrees down to -6.4 degrees and longitude from -87.2 degrees to 26.6 degrees.

How would I preserve the east-west distances and let the shape change? By way of comparison, the northern tundra stretches about 2400 miles on the original map and about 740 miles when shape is preserved on a sphere.

Comments

  • jslaytonjslayton Moderator, ProFantasy Mapmaker
    edited November 2021

    You need to define what the map projection is that has the current shape. Then reproject the image to put that distortion into the image before pulling it into FT.

    The simplest solution that I know is ReprojectImage from http://www.fracterra.com/ReprojectImage.zip (unpack and install - take note of where you install it as it doesn't install its own icon on the desktop or start menu). I will admit that I'm biased, though. Pick your image, pick your distortion, adjust any scale or aspect as needed, then save the image. When you import that image into FT, it will be mapped correctly to a sphere in the Equirectangular projection needed by FT's input system.

    Ralf did this sort of thing a very long time ago. He was kind enough to post his tutorial at ft.PDF (jhendor.de) where it still resides.

    jbclaypool
  • Thanks, I'll try that out.

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