Bug: Duplication offset about rnote

[giannissc]

I have opened another round of bug and feature requests for you.. I hope you don´t mind! 😅 It is not all bad though I have noticed significant performance gains with the last two updates as well!!

[flxzt]

Not at all :) But no promises when the issues will get fixed / improved, because developing Rnote is just a hobby for me right now. I already fixed this one upstream though!

[giannissc]

No don´t worry about it, I know the drill :) I also had a look at the documentation for gtk-rs when I find some more time I will start playing around a bit with it and then I can help…but not promises here either… haha

The only things that I consider priority are the undo/redo (#23) bug and the missed strokes (#28). If you could point me to their code I could have a look an see if anything seems wrong!

I already fixed this one upstream though!

Should I close this then?

[flxzt]

Again if you need any help please ask :). And the gtk-rs book helped me a ton and the matrix chat channel for gtk-rs is also very helpful for questions with the toolkit.
How the strokes and their behaviour work is that they are split into lists of components (which are fields of the "StrokeState" struct). For example trash_comp to hold the state if the stroke currently is trashed, select_comp to hold the state of selected strokes, render_comp to hold the pixel data, etc.. StrokeState has methods, which are the systems which iterate over these lists and modify their state. (its an ECS pattern, check this video for a better explanation. The undo / redo is in "/src/strokes/trash_comp.rs", more precicely the "undo_last_stroke()" and "redo_last_stroke()" methods. They use the chrono_comp which has holds the variable t, which must be incremented wherever a stroke is inserted or modified. This is needed because the lists don't retain a chronological ordering, meaning iterating over them is more or less in arbitrary order. This way of doing it does not support undoing / redoing of something else than trashing (e.g. translating or resizing a selection), so I want to refactor it into something better anyways