setting time rate to zero (7 key) doesn't pause scripts

I can't reproduce this bug on version 0.11.1 of Stellarium

I guess this problem is still present. Though the timerate is set to zero, the script continues to execute.

Seems like QScriptEngine doesn't provide pause functionality.
From what I understand, there are no direct ways to pause script evaluation. The possibility is to attach a QScriptEngineDebugger and interupt the script execution.

If someone has any other ideas/qt hacks, please let me know. I am willing to fix this.

I would suggest to keep the timerate setting and script pausing separate for mainly 2 reasons. One, the user might expect the script to resume from pausing with last known timerate - which requires to remember the last timerate etc.

Second - Currently, the script rate changes are performed (setScriptRate()) relying on the wait() used inside a script. i.e. on an assumption that the script uses wait() calls and thereby tweaking the wait() time. However, this is not good for pause, since for lengthy scripts which doesn't use wait() at all, the pause will never happen. A better approach is to identify each script statement execution and once a gui pause event is received, intercept the script execution.

So we can keep the timerate and script pausing separate for now, unless until it is really necessary.
For a user who wishes to pause a script, I am implementing a script pausing based on QScriptEngineAgent. We can have a keyboard shortcut to map this to pause/play scripts - much like in old Stellarium versions (0.9.1)

Patch for script pause functionality.

Some of the options considered were :

1. Use a QScriptEngineDebugger and issue intercept
2. Use QScriptEngineAgent and wait and processEvents() until resumed.
3. A hybrid signal-slot, with a signal emitted during pause , which is caught by a JS slot.
 The JS slot will wait until a resume signal is received.

The first method is a bit of overkill, and will need tweaks for linker/include options.
The agent based method requires explicit calling of processEvents() (The QScriptEngineDebugger does the same thing - uses QScriptEngineAgent, but is transparent )
The JS slot to wait - I don't think the slots are really meant to block, generally they're only seen used with getters/setters.

The patch uses the second approach. It ensures pause-on-next-statement, but please keep in mind that there are situations wherein the pause is not obvious. For eg: if the previous statement had continuous operations like fading, zooming to an object etc. it will continue for the configured duration.

The shortcuts.
Old stellarium versions had key '6' for pausing and 'K' for resume. Since 'K' is already taken for timerate setting, I'm using '5' and '6'.
Also have key binding for stopping script. Please reassign them if required.

Thanks for patches.

Diff: http://bazaar.launchpad.net/~stellarium/stellarium/trunk/revision/5354

James, how HWE Next Project related with Stellarium?