Northern Eclipse Help Reference

 Polygon tool

This tool is used to outline a polygon on an image. The drawn polygon can be used for measuring (see measure) objects within the box created, for selecting color threshold values for the selected region (see threshold), cropping the selected region of an image (see crop),  or cutting an area out of an image (see cut). To measure objects with this tool, threshold an image and then objects within the image can be outlined for measuring. It is also possible to create many boxes on an image (and/or combine with traced regions) before measurements are executed. Regions may be removed by selecting Remove all selections or Remove last selection.


All objects completely within the outline, those touching the outline, or all objects that have a center of gravity within the outline can be measured depending on how the data options have been set (See Data Options).

Example: To draw a polygon on the image, click on the polygon selection tool and then move the mouse cursor to the starting point on the image where the polygon is to be drawn. Click the mouse once on the starting position. A line will follow the mouse cursor. Move the mouse around and then click it once to mark a second position.

At this point only a single line will be drawn. A third click will create a triangle. Continue clicking the mouse at various locations and a more complicated polygon will be created. To finish off the polygon, double click the mouse at the last position.


Threshold the image and then Measure. At this point all of the selected objects in the field outlined by the ellipse will be measured and a Data Results dialog box will appear. In the Data Results menu, click on LOG to DDE to send the data to Excel or the currently connected program supporting Dynamic Data Exchange (see DDE).


This tool will make measurements (without thresholding) of all the regions placed on an image as long as in the Data Options section, under Object Policies, Objects Partially inside selection are set to Cut by selection.


Hint: If this function is used as a Visual Basic routine, Visual C++ routine or macro, the same size box may be applied to new images repetitively as a mask (or template). Selected regions can be saved as regions (*.msk files) with the use of the Save current selections option.


See Also

Rectangle Tool
Circle Tool
Trace Tool


Table of Contents
Function Reference
Menu Reference
Toolbar Reference