# Protractor Help

## Version 1.0 10 February 2019

## Summary

This is a screen protractor.
The dial can be rotated and there is also a rotatable cursor.
There is also the ability to rotate the compass image relative to the dial to represent compass deviation.

## Relative Rotation Marker

The whole dial can be rotated by dragging on the red marker while holding the alt-key down.
The angular position of the red marker is displayed in red text in the upper quadrants of the compass image.
There is an alt-lock button in the upper left of the screen for use on touch devices which do not have a keyboard alt-key.
This acts as an alt-key lock button.
The relative rotation can also be set by double-clicking on the red marker while holding the alt-key down and entering the desired relative rotation in the dialog box which is displayed.

## Angle Marker

The cursor line can be rotated by dragging on the blue marker.
The angular position of the cursor line and blue marker is displayed in blue text in the lower quadrants of the compass image.
There is an anticlockwise button in the upper left of the screen which displays the angular position anticlockwise as indicated on the inner scale.
The cursor line rotation can also be set by double-clicking on the blue marker and entering the desired rotation in the dialog box which is displayed.

## Compass Deviation

The compass image can be rotated relative to the dial by double-clicking on the centre of the compass image and entering the desired rotation in the dialog box which is displayed.
On touch screens use single touch.

## Compass Images

The compass image can be changed by double-clicking on it (but away from its centre).
There are three images which are displayed in turn.
On touch screens use single touch.

## Operation on Touch Devices

Double-clicking is not available on some touch screens.
Alternatives have been provided where necessary.

## License

The Protractor is Copyright © 2008-2019 Harry Whitfield (G6AUC).

This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version.

This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA

## Widget Concept, Coding and Documentation

Harry Whitfield (G6AUC)