after some experimenting and combining with idea/solution from @Unwave, I have come to alternative solution which works very well in my case. Anyway, if someone else encounters similar problem, here is what I did:
- select all edges of the terrain mesh and mark them as seams.
- select all mesh faces and do the UV unwrap function (all polygons are now spread separately across the texture iamge)
- select all mesh faces and select reset from UV unwrap (all polygons are now in the same spot - overlapping)
- select all faces in the UV editor, scale and move them over the desired texture.
Basically what I did is exactly what @Unwave said, except here I didn’t change the mesh and overlapping are triangles and not squares - only half of the texture is used because of this.
This obviously wouldn’t work with textures where random texture seams are not an option, but in my case where there is grass involved, this actually improves the impression of randomness.
See example picture top with and bottom without visible edges: where the polygons are more dense and evenly placed, there is clearly visible that texture repeats. where the polygons are more “random” the grass appears somehow more realistic - there is no indication that there is repeat involved.
Best regards, Pawks