Sunday, 3 November 2013

Circular repeater geometry in Revit

In previous posts I have described how easy it is in Revit to use a circle as a rig to host regular geometric shapes like squares and hexagons.  It occurred to me the other day that circles would also be ideal hosts for parametric stars;  put that together with Repeaters and you get some interesting possibilities . . .

Here is how to create a parametric star:
  • Create a new adaptive component;  
  • Place a point at the origin; make its reference planes visible
  • Set the horizontal ref plane as the work plane
  • Place a reference line circle onto the point
  • Make its radius dimension into a parameter
  • Select the circle
  • Divide Path
  •  It will create a divided path on top of the circle with 6 nodes
  • Create another Adaptive component
  • Place two points, and make them adaptive
  • Place a line between the points, remembering to enable "3D Snapping" first
  • Save the second family (eg. as "AC 2pt Line")
  • Load it into the first family
  • Place one of the components onto two non-adjacent nodes
  • Select the two-point component and click on the Repeat command
  • You should end up with a triangle
  • NB.  if you placed the two-point adaptive line component onto adjacent nodes you'd get a hexagon
  • Actually, a triangle is only half of what we want, but we need to backtrack to get the correct result - so, UNDO the repeat command
  • Place a second two-point adaptive on alternating non-adjacent nodes
  •  Select both lines and click on Repeat
  •  You should end up with a six pointed star, which is now a "Repeater"
  • Select the divided path, and change the number of nodes to 5, giving you a five pointed star
  •  Change it to 4, which gives a cross (not so useful)
  •  Change it to 3 for a triangle
  •  Change it back up to 7
  •  And then to 8 - this gives an eight pointed star that could be useful in tiling patterns when repeated itself on a divided surface
  •  As the number of nodes increase, the shape becomes closer to a circle
  • Now all you need to do is turn the number of nodes into a parameter to get yourself a one-point adaptive parametric star component
  • Oh, one more thing - you need to make the nodes of the divided path not visible otherwise they will show up when this component is placed in a project or another family

How useful is this going to be?  We'll investigate that in a future post . . .
Here is one possible use - geometric patterns

1 comment:

  1. Nice Article on Revit Training
    thanks for sharing it
    New Delhi , India