This is quite a big issue on our end, and I believe a pretty straightforward setting would fix it.
The problem is this:
When sprites are scaled, the sampling of the alpha channel for transparency will quite often prematurely fade pixels at the very edge of the sprite, if you’re using bilinear filtering.
This is understandable for self-contained sprites, but it’s a problem for sprites that are supposed to tile together.
Here’s a simple example of a tiling grass sprite, that tiles perfectly fine in photoshop, but gets this issue in-game:
I believe this can be solved, by giving the user the ability to specify extrusion for the alpha channel in the image settings. That way, the texture filtering will get the correct alpha value, and the mesh will handle the clipping properly.
My suggestion would be to add four checkboxes per-image:
[ ] Clip top
[ ] Clip right
[ ] Clip bottom
[ ] Clip left
In my case, I have a set of tiling wall structures that need to fit together perfectly, and they all need harsh/non-blended clipping, but only in specific directions, so I need to be able to mix them.
This is likely the biggest issue that is currently affecting our game