Persist netgraph editor's viewport – Save and Restore (Open) #849
Description
Who would benefit from this feature?
Users
What is this feature about?
Users working with large or complex netgraphs who want to continue exactly where they left off.
Example:
- Teams sharing netgraphs and expecting the same view to appear when another person opens the file.
- Anyone who frequently switches between different areas of a netgraphs and needs consistent visual context.
Why is this feature valuable?
The Netzgrafik‑Editor should be able to persist the current viewport (position, zoom level, visible area).
After closing, reopening, sharing, or refreshing the editor, the last used viewport should be restored automatically.
To support this, the data model must be extended with a new JSON element:
rendering (new) -> NetzgrafikEditor -> Viewport
The viewport object should contain all necessary parameters to reconstruct the exact view.
Backward compatibility:
- If no viewport is found in the JSON, the editor must behave exactly as it does today and fall back to the default viewport.
Additional technical work required:
-
Update the migration logic so that existing data without a viewport remains valid.
-
Update the technical documentation: https://github.com/OpenRailAssociation/netzgrafik-editor-frontend/blob/main/documentation/technical/DATA_MODEL_JSON.md
Why is this feature valuable?
- Improves usability significantly, especially for large or multi‑regional Netzgrafiken.
- Saves time by eliminating the need to manually navigate back to the working area.
- Ensures consistent context when sharing Netzgrafiken with colleagues.