Mark Angle

Marks the most recently selected angle or angle measurement as the angle to be used for future rotations and polar translations. To enable this command, your selections must include either three points or an angle measurement.

Use a marked angle for a transformation when you want your transformed image to move as the marked angle changes.

Rotations and polar translations can use either a fixed angle (such as 45º) or a marked angle (such as DABC). When you rotate by 45º, the angle of rotation never changes, but when you rotate by DABC, the rotation changes as the positions of points A, B, and C change.

You can mark an angle defined by three points, or you can mark an angle measurement or calculation.

Marking an Angle Using Three Points

1. Select the three points defining your angle. First, select a point on the initial side of the angle, then select the vertex, and finally, select a point on the terminal side of the angle.

For instance, if you select three points arranged as shown above, in the order A, B, C, the result will be a marked angle that specifies the counter-clockwise rotation shown by the arrow.

2. Choose Mark Angle from the Transform menu.

A brief animation from the initial side to the terminal side confirms that your angle has been marked.

Marking an Angle Measurement

1. Select the desired angle measurement, parameter, or calculation. The units of the value must be either degrees or radians.

2. Choose Mark Angle from the Transform menu.

The selection will flash briefly to confirm that your angle measurement, parameter, or calculation has been marked.

You can change the marked angle measurement while the Translate or Rotate dialog box is open by clicking on the desired measurement, parameter, or calculation in your sketch.