Parametric Patterns IV: Projection


The Ramones changed rock with recombinations of 3 or 4 cords and we have arrived at Pattern 4.  Therefore, even the beginning Vasari/Revit user should now be equipped to make a parametric “Now I Wanna Sniff Some Glue”, although you might have to sniff some glue first.  [Note, neither Mr. Kron, Buildz or its subsidiaries endorse the sniffing of glue.]

The ideas I’m translating here are kind of raw, they aren’t in themselves projects, but they can be the underpinning drivers for real projects or sets of relationships that you might take on in a project.  One of the fun things that happened a couple days ago was seeing an opportunity to recombine some of these patterns into something new.  (You can combine the Post Shadow pattern shown below with the Altitude/Azimuth Controller pattern to create your own geometric Sun Path, I’ll do a separate post on this.)


“Produce a transformation of an object in another geometric context.”

Shadow Casting


“Simulate a row of posts casting shadows on the ground as a light moves by.”

Shadow Casting
Surface Sampler/Spotlight


“Project a collection of points onto a surface.” & “Model a metaphorical spotlight projecting a circle shape onto several surfaces.”  For this example I combine a couple of the exercises.

Surface Sampler
Pinhole Camera


“Model a pinhole camera.”  A pinhole camera uses a very small hole in a surface to create a projection of an object.  This projection alters the scale and inverts the target.

Model a Pinhole Camera, with apologies to the Ramones

Download the datasets from here.


  1. What is the real reason why splines can't be a closed loop? This has been an issue since version 1. Is Autodesk even aware of this problem?

  2. Yes, it's a drag, and Autodesk is aware . . . not sure what the technical reason is for not having a closed spline, but I know there is one.

  3. Thank you very much for the nice movie.
    I have a similar problem where i need to project a planar spline on a wavy surface but with 100% precision. Is there any magic trick to solve it faster? Here is the problem (I`m gaby424):