The blurriness you're experiencing with Spine assets in Unity, compared to a PNG of the same size, is likely due to the texture import settings in Unity rather than the texture packing settings in Spine. When Spine assets appear blurry in Unity, it's often because of the Filter Mode setting on the texture import settings in Unity. By default, Unity might use Bilinear or Trilinear filtering, which can cause textures to appear blurry, especially when they are scaled or not displayed at their native resolution.
To address this issue, you should change the Filter Mode of your Spine atlas textures in Unity to Point (no filter). This setting disables texture filtering and displays the texture pixels as they are, which can help retain the crispness of pixel art or sharply defined edges in your textures. Additionally, ensure that the Max Size and Compression settings in Unity are appropriately set to prevent Unity from automatically resizing or compressing your textures in a way that degrades their quality.
For more detailed guidance on adjusting texture import settings in Unity for Spine assets, refer to the Spine-Unity Documentation.
