| To draw dimensions, you must first choose Plan > Create dimensions 
          or select the Create dimensions tool.   
           Create 
            dimensions tool
  You can create a new dimension in the 
          plan using one of these ways: 
          Click at the start point of the new dimension, click at its end 
            point, then click a third time after moving the mouse pointer to choose 
            the size of the extension lines drawn at each end of the dimension 
            line. Move the mouse pointer on the border of a piece of furniture, the 
            wall side or the room side you want to measure, double-click to accept 
            the temporary dimension draw in the plan, then click a third time 
            after choosing the size of its extension lines.Press Ctrl key (or alt / option key under macOS) and click at the
            start point to display the modification 
            dialog box which will let you create an elevation dimension measuring the height 
            of an object when shown in the 3D view. When you draw a plan dimension, the new dimension won't have any extension line if you 
          don't move the mouse between the second and the third click.At any time you may press the Escape key to cancel the creation 
          of the current dimension.
 While choosing the end point of a new dimension, each mouse move updates 
          in the plan its size and the length it displays.
 
           
            |  |  |   
            | Creating a dimension without extension lines
 | Creating a dimension with extension lines
 |  To end the drawing of dimensions, choose Plan > Select  or 
          select the Select tool.  
           Select 
            tool
 |