Hi! I'm loving the tool, it makes texturing (something I've always struggled with) quite fun. Good luck with the Steam release!!
I have a couple things that would make this program a lot better and easier to use that I would appreciate you thinking about:
1: While holding control or shift, make moving a point keep the ripper in a square/rectangular shape. For example, if I move the top right point of the ripper, the top left point will match its Y-value, and the bottom right point will match its X-value. Another cool option would be a button to "straighten" the edges of your ripper after adjusting.
2: Pixel snapping. I want to be able to snap my ripper points to pixels or a set value. This is pretty easy, I've done grid systems before in Unity, you just need to use Mathf.Round and some division.
3: An option to apply tiling to only the horizontal or vertical sides of an image, instead of all 4 at once. Sometimes I only want something to tile in one direction. Also, the tiling window needs work, the sensitivity for moving it around feels off, and it doesn't work well with non-square images.
4. Resizable windows. Let me drag the edges of each window to make them bigger/smaller so I can see things easier, especially when tiling. Even better if I can separate each window and put them on different monitors.
5. Saving. I think this could even be done with a simple JSON format, storing the file paths of each image, their positions in the image window, the ripper positions and points, and then the output from each ripper's position/scaling/tiling settings. There really isn't too much data to save.
I think that's about it for now, again, good work and I hope there's more updates in the future! I'd love to hear your thoughts on these ideas, and if you need any clarification or help with the logic for them let me know.