Simlin is an open source tool for creating and editing System Dynamics models. You can try it today at https://simlin.com.
- Shift-click on the background to reposition the canvas (and drag selection doesn't currently do something).
- Click the blue edit button to show/hide new object creation tools.
- use these tools by highlighting one of them and clicking on an existing item (in the case of "link" and maybe "flow"), or on the background of the canvas.
- Create a new flow by clicking-down on a stock (or on a blank spot on the canvas) and dragging.
- Detach + reposition/reattach flows + links by clicking-down on arrowheads and moving them over a new target. The new target should highlight as green.
- Click on a variable name to edit the name.
- In equations, you can either refer to the variables like
"var name"
(with quotes), or likevar_name
(replacing spaces with underscores). - The arrows in the bottom right are Undo and Redo - there is currently a 10-change limit for undos, and if you undo into the past + make a change (like moving something), you won't be able to redo-back those changes.
- If you mouse-down and drag a label you can adjust its position relative to the variable.
- If you select a variable that is under the "search" box, the sheet showing variable details will cover that part of the model (you can manually shift-click the background and reposition the diagram to get out of/around this).
- Drag selection isn't implemented yet.
- You can only detach the arrowhead of a flow, not the origin/source end.
- Undo/redo only applies within a browser tab. If you restart your browser (or reload the page), you will lose the ability to undo to before the reload.
- Only straight-line flows are supported for now.
- Maybe more! See the Issues page for additional info (and to report a bug or usability issue)
- GCLOUD: Make sure that you have installed the Google Cloud CLI and its firestore emulator. You can follow this guide.
- wasm-bindgen. In addition, install the latest version of wasm-bindgen:
$ cargo uninstall wasm-bindgen-cli $ cargo install wasm-bindgen-cli $ wasm-bindgen --version wasm-bindgen 0.2.92
# dependencies; ignore warnings
$ yarn install
# build everything -- necessary to compile the rust simulation engine to WebAssembly
$ yarn build
# (the next 3 commands don't exit on their own -- they should be run in 3 separate terminals)
# start a local Firestore instance using the Google Cloud SDK
$ yarn start:firestore
# in another tab:
$ yarn start:backend
# in third and final tab:
$ yarn start:frontend
Now to the browser!
You can start local development + iteration on http://localhost:3000/