Midpoint Aspect lines – tap a midpoint record to show the aspect
Tap again to restore the standard aspect line display

Midpoint Aspect Lines for Bi-Wheel Chart. Directed Sun by Solar Arc is aspecting Mars/Uranus natal midpoint by an opposition. Note the listing now shows single planet/point to planet/point midpoint.

Midpoint Aspect Lines for Natal Chart. Pluto is in aspect by square to the midpoint of Sun/Mars. Note the listing now shows single planet/point to planet/point midpoint.
Midpoint aspect lines can be shown for all types of charts, except antiscia charts.
Aspects include those to/from the Asc and MC.
Asc and MC are not shown in a bi-wheel setting
If the Asc and MC are not shown in a bi-wheel chart the midpoint aspect is calculated and is listed in the midpoint table but the midpoint lines can’t be shown if the ASC or MC is the aspecting point.

Midpoint Aspect lines MC aspecting Sun/Moon. Note the listing now shows single planet/point to planet/point midpoint.
Now tapping the same record (MC directed to square of natal Sun/Moon midpoint) in the Midpoint table results in this warning message: