Sunday, September 28, 2014

Divide Path Direction

I have questioned myself the logic when it comes to divide path in conceptual massing environment in the past. Recently I am working on an adaptive component for a panel where it requires a louver as part of the panel. I start with a 2 point adaptive family as a louver blade and nest it to the next family. The next family makes out of a set of reference lines and a frame, I have two edges that I use "Divide" to set up my "array".

I then place the blade family and try to use "Repeat" and lay out a series of blade.

It turns out the blade is going wild! At first I thought I have snapped my AC to the wrong node so it behaved unexpectedly.

After some trial and errors, I learn there is something I didn't realize before. For some reasons, when choosing an edge to divide path, one side of the edge has the node sequence backward; thus it results to an unpredictable array.

There is a hidden setting under the path properties. Select the path, check the "Show Node Numbers" and I am able to see the numbers on the path. Obviously they are going different direction.

The fix is quite easy. Check the box "Flip Direction" under the properties, it will set the path to the correct direction.

Try it again with Repeat and this time it works like a charm.


  1. This happens because when you create a rectangle of lines (linking 4 points), Revit likes to draw the lines in a clockwise (or anti-clockwise) fashion. That means the two opposite lines are always drawn in opposite directions to each other; hence the divided paths are also opposite.
    In order to avoid this, I usually draw the opposite lines separately, in the same direction - that way you don't need the extra step of flipping the direction of the path. It is a good tip though, if you were not able to plan the line direction in advance.

    1. Tim,

      Thanks for your comment. This doesn't happen a lot to me when it comes to divide path but it is nice to know there is a logical way to explain now thus a way fix it if the we did draw it in the opposite direction.