There are two ways to select contours to join. The easiest is to use multiple contour selection. First select a model point within the first contour, then select a point in the second contour with Ctrl and the first mouse button. If two or more contours are selected in this way, they will be the ones joined, regardless of any set points appearing in the dialog box. The second way is to select a point in the first contour and press the Set 1 button, then select a point in the second contour and press Set 2. The latter step is actually superfluous, because if only one join point is set and another point is selected as the current point, that point will be used as the second point.

How the contours are joined depends on the type of object and the options selected by the radio buttons.

1. For closed contour type objects, the contours can either be joined by a closely-spaced pair of connecting lines or concatenated end to end. The connecting lines will be up to two pixels apart, or closer together if the spacing between contour points is less than 2 pixels around the points chosen for joining.
   • If Concatenate is selected, all of the points from one contour will be added after all of the points in the other contour, so that the contours will appear joined at their nearest endpoints.
   • If Join near pts is selected, a pair of connecting lines will be generated between the contours at their points of closest approach.
   • If Auto-choose is selected, the program will automatically choose between these two approaches based upon whether a pair of contours have openings at their ends larger than the distance between their endpoints.
   • If Join set pts is selected, two contours will be joined with a pair of connecting lines between the selected points in the contours.
   Thus, these options give you complete control over the process, but the default Auto-choose will probably do what you want.
2. For open contour type objects, the contours can be concatenated end to end or spliced at the selected points.
   • If Concatenate is selected, a pair of contours will be joined end to end just as described above for closed contours.
   • If Splice set pts is selected, the new contour will contain points from the first contour up to first set point then points from the second contour starting at the second set point through the end of the contour. Other points are discarded.
3. For scattered point type objects, all of the points from the selected contours will be combined into one contour, regardless of which points are selected. No points will be discarded.

When more than two contours are selected, the pairs with the least distance between them are joined first.

The hot key Shift+J can be used in place of the Apply button. It can also be used when the join dialog is not open, when two or more contours are selected. The radio box selections will be remembered and applied after the dialog is closed.

Help Index