You can measure the distance between two objects in the scene using the Ruler tool. When a measured distance is displayed, it is always displayed at the current camera view, enabling you to see the measured distance when working in Orthographic view (Producer Front, Producer Back, Producer Top, Producer Right, Producer Left, Producer Top, or Producer Bottom).
The Ruler tool ( 
) enables you to draw a segment in the Viewer window.
The Ruler tool enables you to measure the distance between two objects or elements in a scene:
The Ruler tool ( ) enables you to view the measured distance update in real time as you translate the objects.
The Ruler remains snapped to non-deforming models because deformations are calculated on the GPU.
If you snap a Ruler onto an object that deforms in time, such as the dress or shirt of a model, the Ruler unsnaps. If you want the Ruler to remain snapped to a model, snap it to an object or element that does not deform in time such as a joint of a model as opposed to the dress or shirt of a model.
You can only have one Ruler in the scene. If you want to create another Ruler, you must first replace or delete the Ruler in the scene.
The Ruler tool ( ) enables you to save the measured distance between two objects or elements in a scene as a Dimension object.
See Saving the measured distance between two objects in the scene.
To measure the distance between two objects in a scene:
Setting the Display mode to Normal, X-Ray, Models Only, or Models Display Wireframe enables you to see objects and models, their bounding box centre (displayed as a Magenta hexagon), and their Rotation and Scaling pivots.
) in the Camera View Display toolbar options (
) (or press Ctrl-Shift-R).
The measuring distance displays and updates dynamically as you start to move the cursor.
The system Ruler "object" is created and displays the distance between the two objects.
Ruler "object" displaying the distance between two objects
To measure the distance between two objects from their surfaces:
Setting the Display mode to Normal, X-Ray, Models Only, or Models Display Wireframe mode enables you to see objects and models, their bounding box centre (displayed as a Magenta hexagon), and their Rotation and Scaling pivots.
) in the Camera View Display toolbar options () (or press Ctrl-Shift-R).
) enabling you to snap to the surface of the object.
The 3D cursor is shown snapping to the surface of the cube.
The system Ruler "object" start point snaps to the surface of the object. The measuring distance displays and updates dynamically as you start to move the cursor.
The cursor changes to a 3D cursor ( ) enabling you to snap to the surface of the object.
3D cursor is shown snapping to the surface of the second object
The system Ruler "object" end point snaps to the surface of the second object and displays the distance between the two objects from their surfaces.
To measure the distance between elements in a scene:
Setting the Display mode to Normal, X-Ray, or Models Display Wireframe enables you to see objects and models, their bounding box centre (displayed as a Magenta hexagon), and their Rotation and Scaling pivots.
) in the Camera View Display toolbar (or press Ctrl-Shift-R).
The system Ruler "object" start point snaps to the center of the element.
The measuring distance displays and updates dynamically as you start to move the cursor.
Ruler "object" start point shown snapped to the center of the light
) over the camera.
The system Ruler "object" end point is automatically positioned at the centre of the camera film back regardless of where you position the cursor.
The position of the 3D cursor ( 
) follows your cursor movement whereas the 3D cursor ( ) is automatically positioned by default at the centre of the camera film back—the camera's default Rotation pivot.
Distance measured from the centre point of a light to the centre point of the camera film back
The system Ruler "object" displays the distance between the centre point of the light and the centre point of the camera film back.
To measure the distance between a pivot offset of an object and the surface of another object:
Setting the Display mode to Normal, X-Ray, Models Only, or Models Display Wireframe mode enables you to see objects and models, their bounding box centre (displayed as a Magenta hexagon), and their Rotate and Scale pivots.
) in the Camera View Display toolbar (or press Ctrl-Shift-R).
The object is highlighted, and the object's bounding box centre (displayed as a Magenta hexagon) and the Rotate and Scale pivots are displayed, enabling you to snap to the bounding box centre of the object.
The system Ruler "object" start point snaps to object's pivot offset.
The measuring distance updates as you start to move the cursor.
The cursor changes to a 3D cursor ( ).
The system Ruler "object" end point snaps to the surface of the second object. The measured distance between the pivot offset of the first object and the surface of the second object is displayed.
To edit the distance between two objects:
) (or press T).
The system Ruler "object" remains snapped to the objects and the distance between the two objects updates dynamically.
The system Ruler "object" is shown as a dashed line when it is occluded, as seen in the following figure.
Ruler shown partially occluded
Except where otherwise noted, this work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 Unported License