Eliminating Flat mapping stretch marks:
This technique will work best with textures that have small random patterns. Here is the front view of a texture that is flat mapped on to a sphere. The front and back view look OK.
Here is the side view, where you can see stretch marks which are caused by the curved surface of the sphere when using Flat texture mapping.
To eliminate this effect, while still in the Texture mapping module of Amorphium, select a small size brush, about the size of the texture patterns, and start moving it around directly on the object where the stretch marks are located, rotating the object as needed. Below is the result of doing this action. The brush won't have any effect on the objects surface, just the texture.
Below you can compare the results with a sphere that is half done.

 

 

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