Wave propagation / shadow from object


I would like to create a preview of wave propagation from a tower. Nothing fancy and definitely no analysis. I just want to “spread” a cone from the top of the tower and have objects (buildings) block the propagation to show the “blind spots”. Unfortunately, I don’t know which function can do it. I tried to look for some wave propagation tutorials but all I can find are architectural tutorials about wave roofs or walls. I also thought about placing the sun on the top of the tower and using the shadow as a pointer, but I think there may be a better solution.

Tower with buildings

Tower with propagation cone

Tower with propagation cone and “blind spot”

I would be grateful for pointing me in the right direction. I think there must be some clever way to do this but I don’t know even where to start.

Hello - something like in the attached file?

WaveShadow_maybe.3dm (1.1 MB)



It looks exactly like the thing I need. How did you do this?

Hello - a bit of work actually-

Set a camera to look down the wave cone surface (named view in my file).
Get a Silhouette of the object,
Scale the resulting curves - just the very outer ones actually - from the point of the cone.
Loft the curve(s) back to the point of the cone, or ExtrudeCrvToPoint.
Lots of trimming…

WaveShadow_PG.3dm (188.5 KB)


Thank you for your help. Is it possible to automate that process? I was thinking about finding multiple “blind spots” with one antenna and many buildings around.

Thinking… probably-maybe. But not this minute… I bet Grasshopper can help.


Here’s an attempt with Grasshopper mostly. Ladybug might have a component for this but I haven’t used it in a while and forgot where it is. But if you download it and spend a day on you tube you’ll pick it up fast.
I tried with isovist in GH and it seems ok. It solved intersections from a point which matched the shadow outline pretty well. The black lines were drawn with extend from tip of cone to object intersection point, then I used extend to the floor plane and these points lined up as well. Nice thing about isovist is it lists some things like obstacles hit and distance from cone etc. I didn’t finish up making the solids ala Pascals example don’t really know if this will help but was an interesting problem.

Thank you both of you @pascal and @3dsynergy.
I will test your solutions, probably combine them and I will come back if I have something worth sharing.

@s.urbanski: if I understood your question correctly, you could mesh your breps and use Mesh shadow in grasshopper.