Project sampling is working strange.

I set the project's sampling to Tnilinear.

And I made an 80x80 square.

However, if you give this object an angle value, pixel staircase occurs.

But there is something more confusing to me than this.

We created 4 different objects of size 80x80.

Only the first object has pixel staircase.

This object, unlike other objects, is that the painted range is a border.

Please check in the attached sample project.

What am I misusing?

Or is there any information I don't know?

the first sprite has no border, so it is harder for C3 to render it. All the others have a one pixel invisible border, so C3 can smoothly rotate it.

To add to Allan's comment, you can click Crop button on the toolbar and the 1px transparent border will be added to your sprite.