*************** Troubleshooting *************** Some common problems people may run into when using drivers. Scripted Expression =================== .. figure:: /images/animation_drivers_troubleshooting_autorun-graph-editor.png An Auto-execution warning in the Drivers panel. .. figure:: /images/animation_drivers_troubleshooting_autorun-info-header.png An Auto-run warning in the Info editor's header. By default Blender will not autorun Python scripts. If using a *Scripted Expression* Driver Type, you will have to open the file as *Trusted Source*, or set *Auto Run Python Scripts* in :menuselection:`User Preferences --> File --> Auto Execution`. .. list-table:: :widths: 40 60 * - .. figure:: /images/animation_drivers_troubleshooting_autorun-file-browser.png The Trusted Source checkbox in the File Browser. - .. figure:: /images/animation_drivers_troubleshooting_autorun-user-preference.png The Auto Run Python Scripts checkbox in the User Preferences. Rotational Properties are Radians ================================= Parts of the User Interface may use different units of measurements for angles, rotation. In the Graph Editor, while working with Drivers, all angles are Radians. Intra-armature Bone Drivers can Misbehave ========================================= There is a `well-known limitation `__ with drivers on bones that refer to another bone in the same armature. Their values can be incorrectly calculated based on the position of the other bone as it was *before* you adjust the current frame. This can lead to obvious shape glitches when the rendering of frames has a jump in the frame number (either because the blend-file is currently on a different frame number or because you are skipping already rendered frames).