Manipulating the Timestream

[stonier]

Two parts to this project - basic pause/step/resume functionality and a time travel capability. The latter needs to go through a design step, starting that here.

Backend

• [x] pause/step/resume functionality, with ign services to manipulate these
• [x] option to be able to start paused (w/ #180)

Frontend

• [x] connect to the pause/step/resume functionality in the backend
• [x] decision about whether to include time travel in Milestone #2 or punt to #3.

Documentation

• [x] For developers in the Delphyne Guide (anything curious + command line tool instructions)

Demo Goal

Seme of these will have dependencies from other milestone subprojects.

• [x] demonstrate pausing, stepping and resuming a simulation from the visualiser
• [x] demonstrate pausing, stepping and resuming from the command line
• [x] demonstrate starting a simulation paused (w/ #180)

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Fixes and Polish

• [x] multi-step should run at the same speed as the simulation (#326)
• [x] put the time control widget over on the right hand side of the screen in our default layout
• [ ] button styling to match the system's option (https://github.com/ToyotaResearchInstitute/delphyne-gui/issues/75)
• [ ] Gui key-bindings (P, S, R) (https://github.com/ToyotaResearchInstitute/delphyne-gui/issues/76)

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Priorities

Punting time travel to either a separate meta issue or milestone #3.

Risks

• Time Travel related work is more complicated and might take longer than expected (we did one for behaviour tree monitoring/playback some time ago).

[stonier]

Punt on the time travel, planning that it should be a widget once that framework is finalised. See RViz Style Widgets for information.

[caguero]

Backend

The main play/pause/step functionality was introduced in #137.

The option to be able to start the simulation paused has been implemented and tweaked in the following pull requests:

• #189
• #208

There were a couple of tweaks and bug fixes in:

• #211
• #227

The state synchronization with the frontend is enabled since #229.

Frontend

The play/pause/step functionality has been connected with the backend in # 44.

The state synchonization with the backend is enabled since # 52.

[caguero]

The documentation for manipulating time streams have been added to the Delphyne Guide.

[caguero]

Here's a video that:

• Starts a simulation paused.
• Shows how to resume, pause and step the simulation using the GUI.
• Shows how to resume, pause and step the simulation from the command line.

This video is marked as "unlisted", so effectively only people with the link can view it. Let me know if you foresee any problem with this video configuration.

[clalancette]

I think we've gotten the first pass of this done now, so I'm going to close this out. Please open separate issues for any problems or new features that come up.

[stonier]

For Milestone 3:

• Show the simulation time-step size in the time widget (https://github.com/ToyotaResearchInstitute/delphyne-gui/issues/77)
• Fast forward workflows (#327)

[stonier]

Move the remaining jobs to the final M2 meta, #378