cast shadows with point light source

I made a definition that obtains cast shadows from point light sources (the rays aren't parallel but start from a certain point). File is attached.

1. any simpler way to obtain this?

2. any idea why the Region Union component at the end doesn't work?

Thanks!

later edit: If the object doesn't have convex parts or holes, you can also project the vertices and qhull them (which is lighter)

Attachments:

DIY CAST SHADOWS.gh, 99 KB

Replies to This Discussion

Permalink Reply by Erick Vásquez on June 11, 2014 at 12:54am

Hi Andrei, this works inversly, by culling the vertices of the base plane, so the next step is fix the facet boundaries, this works fine and with holes too, but slooow if you want good results.

Attachments:

140610_DIYCASTSHADOWS_ev.gh, 96 KB

Permalink Reply by Andrei Raducanu on June 11, 2014 at 10:05am

Hey, interesting approach!

I made another version, based on your idea. It is still slow, but uses the actual vertices of the mesh. Take a look if curious:

Attachments:

DIY CAST SHADOWS 2.gh, 99 KB

Permalink Reply by Erick Vásquez on June 11, 2014 at 11:44am

construct mesh... good point! so fast with GetOutlines from viewport, this is the original script. click to animate

Permalink Reply by Andrei Raducanu on June 14, 2014 at 7:21pm

This looks like a great approach, but the definition would be really helpful.. could you upload it? Thanks anyway about the tip!

Permalink Reply by Andrei Raducanu on June 17, 2014 at 2:34pm

can you input the views parametrically or you need to build them in rhino beforehand?

Permalink Reply by Erick Vásquez on June 17, 2014 at 4:46pm

I would be nice if someone improve this script for work with planes or vectors for work parametrically not with viewport, this is a call to the scripting community haha!
the advantage of using this script is to obtain the boundaries of a dirty mesh. see attachment

Attachments:

140617_PtShadow_ev.3dm, 323 KB
140617_PtShadow_ev.gh, 20 KB

Permalink Reply by Erick Vásquez on June 17, 2014 at 5:27pm

So let's back to my first slooow definition.

Attachments:

140617_DIYCASTSHADOWS_ev.gh, 40 KB

Permalink Reply by Andrei Raducanu on June 21, 2014 at 3:56pm

hey, thanks for those options! sorry for the late reply, just got to check them out now. The first two (in the 140617_PtShadow_ev.gh file) don't think are geometrically correct though..

Permalink Reply by rebecca on July 20, 2018 at 1:53pm

Hello!

Is there a way to update the last script (where it includes projecting unto nearby surfaces (as when the bunny is in the corner of the room) to include a shadow project for axonometric, isometric, plan oblique, one-point perspective, two-point perspective?

Thank you,
Rebecca

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