Hello everyone,
I have a question regarding mesh shadow operation in grasshopper. I’m posting in serengeti, though, because I mostly use the WIP, and because the problem I have also manifests in R7.
I’ve been dealing with what seems to be a glitch that’s somewhat of a headscratcher.
When dealing with mesh shadows I get a failed result (appears to be arbitrary) - with the only error message “shadows were not cast onto the plane”.
Here’s my situation:
- I have 18 meshes floating in space in a somewhat spherical distribution:
NOTE:
They’re all the same mesh, oriented to multiple locations.
- I have a bunch of planes (x92) corresponding to specific collisions between each mesh and 92 objects:
- Using the data from the planes, I generate shadows as I’m in need of their projected outlines at each specific location:
- However for some reason at least one of the shadows fails for no reason.
-
here’s a close-up of said failing shadow-plane:
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nothing really different from all the other meshes/planes other than their location…
-
here’s the sinister bug in action:
- Interestingly, if I move the mesh in any direction by a miniscule amount (like 0.001), the shadow works:
Yes, why not just move the failed ones a miniscule amount and problem solved, right?
Well that’s exactly what I’m doing, however it’s not convenient for the precise fabrication this is intended for.
Another work-around at the moment is literally projecting the mesh to the plane:
Why not just do this for all meshes, right?
Because: It’s unpredictable; if I do exactly that what happens is I get new mesh shadow errors which will require more work-arounds.
Definitely a head-scratcher.
Why does this happen?
I appreciate your feedback.
Here’s the file with the sample if it matters:
shadowproblem.gh (862.5 KB)