I saw somewhere a tutorial about how to take image, cut it and blur the edge of texture on transparent background. Then import it as decal or texture in blender and have a nice, smooth transition. But i forgot where and what exactly i need to do in Gimp or Photoshop. Can anyone help?
Use blender’s texture system. Under all the images in the texture settings for the material add a blend texture. Deselect color and select alpha. Then on the main material settings set the alpha all the way down to zero. To control the edge fade and how sharp it is you can mess with the color ramp under the blend texture. If you need any more help just ask.
a sample file would be appropriate here for other peoples looking for this effect!