Driver not updated on dimension changes This is the setup.


Blue Slider.
Green cube with array modifier.
Red cube.


The Blue slider drives the Green cube's array property count when moved up/down and works perfect.


The red box is set to move its location to the green box's location.x+dimension[0].
If I resize the green box or move it, the red cube is following the green box's end correctly (location.x+dimension[0]).


However, If I change the Green box's count property in the Array modifier (with or without Blue slider driver), the red box's location isn't updated at all.

To update it I have to set the cursor in the drivers Expression box and press Enter. It seems like the driver isn't triggered when the array count property changes the cube's dimension.

Any way to fix this?
Give the red cube a dependency on the blue slider. Do this by adding a new variable as the slider location.z, you don't need to use this variable in your expression calculation but having it there adds a dependency that updates the location as you want.