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Cannot add driver for NLA strip influence with new dependency graph
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Description

System Information
Linux 3.14.3 #2 SMP i686 (Debian 7)

Blender Version
2.75 RC1 from http://download.blender.org/release/Blender2.75/

Short description of error
There's no "Add Driver" op in the shortcut menu for NLA strip influence if the new dependency graph is enabled.

Event Timeline

nemyax (nemyax) raised the priority of this task from to 90.
nemyax (nemyax) updated the task description. (Show Details)
nemyax (nemyax) added a project: BF Blender.
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nemyax (nemyax) added a subscriber: nemyax (nemyax).
Joshua Leung (aligorith) changed the task status from Unknown Status to Archived.Jun 12 2015, 1:12 PM

IMO this it is not a bug that drivers cannot be added to NLA strip properties.

In 2.75, some changes were made to resolve some long-standing issues with how the keyframing/driver ops were handling the NLA strip properties. The old way that this was working was never correct, and wasn't the original intended design here, but rather a quick hack that ended up getting put in. The problem is that actions and drivers (at least in their usual forms) cannot be used to control these properties, as actions and drivers are only evaluated once the NLA stack has been evaluated - far too late for whatever results they have to be applied when evaluating the NLA on that frame! That is why these are not able to be driven, and why the old hacky behaviour had to be fixed.

(On second thought, we could probably get this working correctly with the new depsgraph if we made the animation eval op depend on any drivers that affect NLA strip properties. However, while we still have the old depsgraph around, it's best we don't allow creating these drivers anymore in the meantime, as they cannot work correctly and haven't been working correctly).