What causes sprite packer rotation breaking colliders in Unity?

Tight packing with Allow Rotation rotates sprite meshes in the atlas, and a PolygonCollider2D generated from the sprite outline can inherit the rotated, trimmed shape.

How do I catch this when it only happens for some players?

Capture it automatically from the player's device with the full stack trace, the device and OS, the build, and a breadcrumb trail of what they did. That turns a vague complaint into a specific, reproducible issue you can fix without owning the hardware it happens on.

How to Fix Wrong Colliders After Tight Packing With Rotation in a Unity Sprite Atlas

Quick answer: Disable Allow Rotation (and Tight Packing) for sprites that drive colliders, or define the collider from the original sprite's Physics Shape rather than the packed mesh.

Sprites look fine but their auto-generated colliders are rotated or offset once they go into an atlas with Tight Packing and Allow Rotation. The packer's mesh transform leaks into collider generation.

How to fix it

1. Turn off rotation for collider sprites

In the Sprite Atlas Packing settings, uncheck Allow Rotation for atlases whose sprites feed PolygonCollider2D. Rotation reorients the trimmed mesh and the collider follows it.

2. Author an explicit Physics Shape

Open the Sprite Editor's Custom Physics Shape and draw the outline yourself. An explicit shape is stored in sprite-local space and is not re-derived from the packed mesh.

3. Disable tight packing if outlines matter

Use Tight mesh only for rendering. Set the sprite's Mesh Type to Full Rect when a collider needs a stable, untrimmed reference frame.

Catching the ones you can't reproduce

The hardest version of this to fix is the one you can't reproduce — it only happens on a player's hardware, OS, driver, or save state, under conditions that simply aren't present on your machine. A report that says “it crashed” or “it froze” gives you nothing to act on, so the bug survives release after release while quietly costing you players.

Automatic error capture closes that gap. Each failure arrives with its full stack trace, the device and OS, the build number, and a breadcrumb trail of what the player did right before it broke, so even a failure you have never seen becomes a specific, reproducible issue. Fold identical failures into one signature ranked by how many players each hits, and your worklist sorts itself worst-first instead of arriving as a stream of vague complaints.

This is where a tool like Bugnet earns its place. Its SDK captures every Unity error automatically with the full stack trace plus device, OS, memory, build, and game-state context, folds duplicates into one grouped issue with an occurrence count, and ties each to the build it first appeared on — so you fix the problem that hurts the most players first and confirm it is gone when its signature disappears from the next release.

Most of the time the fix is small. Seeing the failure clearly is the part that actually costs you.