Rectangular Mapping On A Sphere:
This tip should help you understand how Rectangular texture mapping a sphere works in Amorphium. Make your gradient texture map the same width and height. The map I used was a 300 x 300 pixel image.
Load a sphere into Amorphium, then load your texture map and select Rectangular mapping. Your sphere should look like the one below.
Front view: Side view:
The main disadvantage to using Rectangular texture mapping on a sphere or any curved surface is stretching along the sides of the image. I added some noise to the gradient texture map so you can see the stretch marks in the side view.
Front view: Side view:
One other way to hide the stretch marks, besides using a gradient bitmap is to use an image with a solid color around the outside edge, like the one below.
Front view: Side view:

 

 

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