GSoC/2019/StatusReports/tusooa

Better undo/redo for krita

This project is divided into two parts.

Snapshot Docker

Implement a docker to allow users create snapshots (shallow copies) of the current state of documents and switch back to them at a later time.

Copy-on-Write Vector Layers

Make vector layers copy-on-write so that the undo/redo system for them can be implemented by replacing the layer with another, rather than store the undo information for each command.

Progress

Done

• Research into solutions for copy-on-write mechanism
• Snapshot Docker
• COW vector layers
  • Make members of KoShapePrivate implicitly-sharable
  • Make KoShape hierarchy implicitly-sharable
• Create undo commands that switch between states of vector layers
  • Stroke & interaction strategies for vector layer interactions
  • Port interaction strategies to the new system
  • Refactor out old undo commands

Links

• Phabricator task
  • Subtask for Snapshot Docker
• Merge Request for Snapshot Docker
• Merge Request for COW Vector Layers
• Merge Request for undo commands

Blog posts:

• An introduction
• Some Strategies for COW
• An example for the undo system to use clones
• Porting the new error-preventing syntax of signal/slot connection to KisAutoSignalConnectionsStore
• Done with the snapshots
• Making Flake as COW as possible
• Getting the interaction running in the image thread (stroke)
• Attending the community's meeting
• And we are done for now, I think