"Use Self" option for drivers throws error unless "Auto Run Python Scripts" is turned on in preferences #118274

New Issue

Erindale · 2024-02-14T14:21:00+01:00

Erindale commented

2024-02-14 14:21:00 +01:00

System Information
Operating system: Windows-10-10.0.22000-SP0 64 Bits
Graphics card: NVIDIA GeForce RTX 3080/PCIe/SSE2 NVIDIA Corporation 4.6.0 NVIDIA 551.23

Blender Version
Broken: version: 4.0.2, branch: blender-v4.0-release, commit date: 2023-12-05 07:41, hash: 9be62e85b727
Worked: (newest version of Blender that worked as expected)

Short description of error
When trying to run a driver using the self target, the error "Invalid Python Expression" is shown.
The console prints "BPY_driver_exec: restricted access disallows name 'self', enable auto-execution to support"
After turning on Auto Run Python Scripts in the Save & Load preferences the self name will work in drivers but show the info "Slow Python Expression".

This is not pointed out in the documentation: https://docs.blender.org/manual/en/latest/animation/drivers/drivers_panel.html
A better solution would be to have the tooltip change from invalid expression to be something more informative eg "enable auto-execution to support use self", or better still, just not having the self function stuck behind a boolean that most would not want to turn on by default.

Exact steps for others to reproduce the error

Add a new object.
Add a driver to the Y rotation.
Set driver as self.location.x and toggle Use Self.
The driver will error.
In preferences, Save & Load turn on Auto Run Python Scripts.
Click into and reconfirm the driver.
Error should update to "Slow Python Expression" and now work.

Edit: It appears that the self name does not work on things such as light power as the error just remains "invalid Python Expression"

**System Information** Operating system: Windows-10-10.0.22000-SP0 64 Bits Graphics card: NVIDIA GeForce RTX 3080/PCIe/SSE2 NVIDIA Corporation 4.6.0 NVIDIA 551.23 **Blender Version** Broken: version: 4.0.2, branch: blender-v4.0-release, commit date: 2023-12-05 07:41, hash: `9be62e85b727` Worked: (newest version of Blender that worked as expected) **Short description of error** When trying to run a driver using the self target, the error "Invalid Python Expression" is shown. The console prints "BPY_driver_exec: restricted access disallows name 'self', enable auto-execution to support" After turning on Auto Run Python Scripts in the Save & Load preferences the self name will work in drivers but show the info "Slow Python Expression". This is not pointed out in the documentation: https://docs.blender.org/manual/en/latest/animation/drivers/drivers_panel.html A better solution would be to have the tooltip change from invalid expression to be something more informative eg "enable auto-execution to support use self", or better still, just not having the self function stuck behind a boolean that most would not want to turn on by default. **Exact steps for others to reproduce the error** 1. Add a new object. 2. Add a driver to the Y rotation. 3. Set driver as `self.location.x` and toggle Use Self. 4. The driver will error. 5. In preferences, Save & Load turn on Auto Run Python Scripts. 6. Click into and reconfirm the driver. 7. Error should update to "Slow Python Expression" and now work. Edit: It appears that the self name does not work on things such as light power as the error just remains "invalid Python Expression"

Erindale added the

labels 2024-02-14 14:21:01 +01:00

Iliya Katushenock added the