Dimensioning Between Virtual Points

You can create dimensions from the line between two points or the mid-plane between two lines, even when that line doesn't exist as an edge.

1. Click Dimension in the Annotation group on the Detailing tab .
2. Select a point (A) as your starting point.

3. Hold Ctrl and select a second point (B).

   This creates a virtual line between points A and B, which will be the baseline of your dimension.

4. Select a third point (C).

   Now you have a dimension between line AB and point C:

   

   If you hold Ctrl when you select point C, the dimension is created between line AB and line BC:

   

5. (Optional) If you select point C without holding Ctrl, and hold Ctrl to select a fourth point (D), the dimension is created between line AB and line CD:

   

6. Click anywhere in the annotation plane to place the dimension.