New incarnation of library

[timjs]

Hi @Kwarrtz,

In search of drawing functionality for Elm, I encountered your excellent library. Because I read you're not planning to support it any more, and I needed automatic positioning functions like the Haskell Diagrams library provides, I created a fork and started experimenting. You can find the result on the Elm package site.

I'm planning to support and extend the library in the time to come. If you'll have some time, I very much appreciate your opinion on the changes I made: naming, functionality, usage etc. Please feel free to contact me or open an issue on the GitHub repository!

The most notable changes are as follows:

• The coordinate system is again in the middle of the canvas, x pointing right, y pointing up, as in your first version. I'm curious to the reason you decided to change this in version 2.0.
• Form is renamed to Collage.
• There is a module with a whole bunch of layout functions for automatic positioning, loosely based on @vilterp's outdated Elm diagrams library.
• Different way of handling line styles (solid, dot, dash, etc.)
• Extended functionality for text in a separate module.
• Events in a separate module.

I hope you'll find some time to give some feedback!

[vilterp]

Hi @timjs, I know you weren't asking me for feedback but elm-collage looks really cool! Glad my old library was able to provide some inspiration. Have been meaning to update it and get it rendering to SVG; probably would have come up with almost exactly what you've made :)

I guess the one thing it's missing that I would have needed for Lemur (my motivating project to make elm-diagrams) is getCoords, which is used to draw the bezier curves connecting different boxes in the DAG editor. Not every project needs it, but you do when you need to draw connectors between different parts of the layout tree.

[timjs]

Thanks @vilterp! Appreciate it 😄 I'd like to take a look into a nice way to connect different boxes. Don't know how to solve that right now. Feel free to open an issue and share some ideas! Btw: Lemur looks interesting, I'm also using Elm Collage for some visual functional programming stuff...

[Kwarrtz]

Hi @timjs ,

It's great that someone picked up this library. Over the past months my life has actually calmed down enough that I was considering actively maintaining this library again, but since you've already done the work to add automatic positioning (an great idea, imo) I may just retire this library for good and let you take up the mantle. I'll be happy to offer suggestions and work on pull requests, though chances are you're at least as knowledgable about the whole thing as I am.

I haven't had a chance to look very closely at your new library yet, but I should be able to get around to that some time this week. If I have any suggestions I'll open an issue on your repo then. As for the coordinate position, it's been so long since I made the change that I don't remember my exact reasons for doing it, but I think it had to do with compatibility. Since I had been planning to create a JS canvas back-end for the library, I was probably trying to get things to line up a bit better with the JS conventions for positioning to make the transition easier. Whatever the reason was, though, I do remember that it was motivated by convenience and stylistic concerns, not necessity, so going back to the old system shouldn't cause you any problems.

If there's ever anything you think I can help with, contact me and I'll see what I can do. Either way, I'm glad this project's been of use, and I look forward to seeing what you do with it.

[timjs]

Thanks @Kwarrtz, I'm happy to receive suggestions if you feel for it! Your lib was really the base of Elm Collage and helped to speed me up a lot!

Let us use the "y points up" coordinate system for now, as it matches Elm Graphics, Haskell Diagrams and regular maths (and relieves my head a lot when thinking about drawing a graphic 😄). We'll see how it will work out. Creating a Canvas backend would be nice in the future. Maybe we'll get some problems implementing the interactive part, but my knowledge of Canvas is not big enough to have a clear idea now.

[timjs]

First pull request for adding scaleX and scaleY is in! Would you mind sharing some thoughts on api naming questions in the discussion?