In order to generate larger textures for my animation (because if the number of textures exceeds 2, the animation cannot be displayed correctly in the game), I modified the parameters of the auto-packing animation script：
However, this resulted in the generated textures not fully containing all of the images.
After my investigation, I found that the coordinates of the placed images were beyond the dimensions of the tex file on your end.
1. Set the parameters to 4096 or higher.
2. Prepare enough images for the animation.
3. Run the script