Curve Intersect

The Curve Intersection (CInt) command is designed to work in 2D with polylines, splines, and other curves. The command finds a common area in a pair of curves, as if the curves were marking the boundaries of a certain area. The usual _Intersect command works in exactly the same way with flat regions (Region). But now you don’t need to convert closed curves to a region, find an intersection, and convert them back to curves. The program will do it all itself. In addition, the program can be used to find common areas in open curves. The program can create gaps, set up layers, save or delete original drawing objects, and trims.

Program capabilities:

• In 1 click, you can immediately find intersecting pairs in many curves, there is no need to call the command hundreds of times for each pair of curves.

• The program considers almost closed curves with a small gap to be closed.

• The source curves can be scattered and rotated in 3D space as you like - the program will project everything onto the XY plane of the current user coordinate system UCS. You can even work with 3D polylines.

• The program only finds pairwise intersections, not a single area common to all selected curves. Therefore, the results of the command may intersect with each other.

• For a pair of closed curves, a common region will be found, for a closed-open pair, only the section of the open curve inside the closed one will be saved, and only completely repeating sections will remain from two open curves.

• You can save trims, that is, non-intersecting areas of each pair.

• You can set the gap between the resulting contour and the trim. That is, the program can automatically offset inward closed curves.

• The results and trims can be assigned to any existing or new layer.

• The source curves can be deleted from the drawing, or saved.

• You can set up to 9 different command styles with different settings and quickly switch between them each time you call the command.

The CInt command is not supplied as a separate plugin, but is included in the AVC_CurveSub plugin and in the AVC Pro collection.

How to use

You can set up all the command options in the AVC Options Palette on the Curve Subtruct tab (all settings are common with this command).

Set up the coordinate system (UCS) - the program will project all curves onto XY.

You can select the source curves before calling the command.

Call the CInt command. If nothing is selected in advance, the program will ask you to select curves. You can work with any finite curves: lines, polylines, 2D polylines, 3D polylines, splines, circles, arcs, ellipses. Infinite rays, xLine, multi-lines, are not processed.

The curve selection prompt has options for quickly switching the style and for opening the settings dialog.

All curves will be projected onto XY. If a gap is specified, the closed curves will be offset inward.

After searching for intersections, all closed contours will remain closed. The result will be a closed polyline or spline. But you can set the result of subtraction for a closed source curve to be a region.

Curves that have not participated in any intersections will remain in the drawing unchanged (even if you set up to delete the source ones).

The process of intersection hundreds and thousands of curves can take a long time. You will see a progress bar and can interrupt the command by pressing ESC.

Watch the command line. The program will display messages about the current settings, any failures and the results of the work.

Options

Select subtracted by layer

This setting is not used in the intersection command.

Result layer

Assign a layer to all the resulting curves. If there is no such layer in the drawing, the program will try to pull it out of your template. Or create a new one. Leave the field empty to save the layer of one of the pair of intersecting curves.

Save Stubs

After intersecting closed curves as regions, the program can still find the remains of the original curves without the intersection zone. This region can be saved in the drawing. Thus, you will get the results of two commands at once - subtraction and intersection. If the original curves were not closed, then the drawing will contain non-matching parts of the curves. If 3 or more curves intersect all-with-all, then you will get stubs from each pair of intersections. That is, a lot of stubs on top of each other. And they will hide the intersection contours under themselves. Therefore, it is not recommended to enable this option.

Stub layer

You can change the layer for stubs. If there is no such layer in the drawing, the program will try to extract it from your template. Or create a new one. Leave the field blank to keep the layer of the original curve.

Gap

Reduce (offset inward) all curves before creating an intersection. Moreover, to obtain stub, a non-reduced curve is used. Therefore, as a result, you will see a gap between the contours of the result and the stub. The gap option does not work for unclosed curves. Note that the Curve Subtract and Curve Intersect commands make a gap in different directions - thus, using both of these commands together with the option to save stubs, you can get a gap on the side you need.

Save gap

Users often forget to zero the gap and think that they are calling a command without a gap. And they get erroneous contours. To avoid these errors, the program resets the gap value by default at the end of the work. But if you want to call the program many times with the same gap value, then check this option and the gap will not be reset. It is better to create a separate settings style in which the gap is specified and this option is checked.

Work with open

Process curves that could not be closed. If you disable this option, all unclosed curves will be ignored.

Create regions

After processing, do not explode regions, but place them in the drawing. The setting only works for closed curves.

Delete sources

Delete source curves if they are used at least for one intersection. If the selected curve was not processed due to failures or simply did not intersect with any other, then such a curve will remain unchanged in the drawing in any case.

Delete subtracted

The setting is not used in the intersection command.

Tolerance

The calculation accuracy setting is on the Common Options tab. Linear tolerance affects the permissible gaps when closing curves, constructing offsets and other operations.