This is a common issue when rendering images side by side, and it's not specific to Spine - it happens with tile maps and any seamless backgrounds in games.
The problem occurs because:
When images are packed into an atlas and then scaled or positioned, texture filtering can sample pixels from neighboring regions or transparent padding, creating visible seams between tiles.
Here are the solutions you can try:
1. Enable "Duplicate padding" in atlas export settings
This copies edge pixels into the padding between regions in your texture atlas. For this to work effectively, your images should have pixels right up to their edge - it won't help if your images have blank/transparent pixels at the edges.
2. Draw without filtering
If possible, configure your rendering to not use texture filtering. This works when:
- Images are not scaled or rotated
- Image pixels correspond directly to screen pixels
- Positions are not off by partial pixels
3. Increase overlap beyond 1px
You mentioned trying 1px overlap - you may need to increase this further depending on your rendering setup and any scaling applied.
4. Adjust atlas padding
Make sure you have sufficient padding configured in your atlas export settings to prevent neighbor region pixels from appearing during texture filtering.
The most reliable approach is typically combining duplicate padding with sufficient overlap between your tiles. Since everything looks perfect in the Spine editor (which displays individual images) but breaks in Spine Pixi (which uses the packed atlas), the issue is definitely related to how the atlas is packed and filtered during runtime rendering.
