To crop an image to exclude parts that are outside of a mesh in Spine, you would typically need to adjust the image itself before importing it into Spine or after exporting it. Spine's focus is on animating and manipulating meshes and images within its environment, and while it offers extensive tools for mesh editing, direct image cropping based on mesh boundaries isn't a standard feature within Spine itself.
However, you can manage the image size and the mesh area in a few ways:
- Adjust Padding and Use Layer Masks in Photoshop: Before importing your images into Spine, ensure they are cropped or have sufficient padding to accommodate the mesh. You can use Photoshop or similar software to adjust the image size or add padding. Layer masks can also be used for non-destructive editing (PhotoshopToSpine script usage).
- Edit Mesh in Spine: If the mesh does not cover the entire image, you can edit the mesh in Spine to include or exclude parts of the image. This won't crop the image file itself but will affect what parts of the image are used and visible in your animation.
- External Image Editing: After exporting your animation or images from Spine, you can use external image editing tools to crop the images further as needed.
For your specific case, where you notice a size difference between the exported image and the original slot's image due to the mesh cutting off areas of low alpha, you would likely need to manually crop the original image using an external image editor based on the mesh boundaries you have in Spine. This process isn't automated within Spine, so adjustments to the image file itself would need to be done outside of Spine, either before importing or after exporting.
