Question to Fletch About Volumetric Light Beam

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Audiologist
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Re: Question to Fletch About Volumetric Light Beam

Post by Audiologist » Mon Feb 11, 2019 12:22 am

I guess the stage and the floor or whatever underneath the light source, when the surface doesn't hit by a light, the light beam doesn't "pass through" it.
Can you check the the skp file that I attached in my previous post?
And see what is actually going on?

Audiologist
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Re: Question to Fletch About Volumetric Light Beam

Post by Audiologist » Mon Feb 11, 2019 6:01 am

Fletch, I think I know why. Let me confirm on few things and I will get back to you.

Des

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Re: Question to Fletch About Volumetric Light Beam

Post by Fletch » Mon Feb 11, 2019 9:40 am

Did you download the file which I posted? the .skp file in this thread here:
Subject: Question to Fletch About Volumetric Light Beam

If you rename a material in SketchUp, and the Twilight Material Dialog box is open, close and re-open the dialog to refresh the names in the list - then you will see your material you renamed "Volumetric"... but it's not as simple as renaming the material to "Volumetric" you must also apply the Template>Volumetric to the material as well. It's VERY IMPORTANT that there is only one box in your scene with the "Volumetric" material applied to it.

To be clear - it's not only that you had an exterior and interior box BOTH painted with Default - then you applied Volumetric Template to the "Default" material - the real problem is that you had 2 boxes, one inside the other, both having the "volumetric" material applied to them. The fact that you applied it to Default was not fundamentally the problem. Although, as I mentioned if you read the thread carefully, it's not a good idea to apply "Volumetric" to "Default" material - because now you have every object in your scene painted with the default material also trying to act as a volumetric material. Can you see how that would be problematic and break the scene?

Audiologist
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Re: Question to Fletch About Volumetric Light Beam

Post by Audiologist » Mon Feb 11, 2019 5:11 pm

OK Fletch, here is what I discovered. I got the material "Volumetric" in my list now. Like you said, in Sketchup material dialog, select a material (color) edit it and save as Volumetric. This part done. And this has nothing to do with the missing part of light beam. As long as the material isn't "Default", is OK.

Second, the bottom of the Volumetric box CANNOT overlapping with the "Floor" or the "Stage" of the scene. The Volumetric box have to be slightly above or under the "Floor" or "Stage" of the scene. And there is a difference when the Volumetric box is above or under. Related to camera position.

If the Volumetric box is under the floor or stage, and camera is outside the Volumetric box, it is absolutely no problem at all.
This was rendered with bottom of Volumetric box under the stage, camera outside the Volumetric box. Everything is fine.
Test 001a.jpg
Test 001a.jpg (70.5 KiB) Viewed 206 times
And this, the bottom of the Volumetric box under the stage, but the camera is inside the Volumetric box. Not OK. The stage blocked the beam.
Test 001b.jpg
Test 001b.jpg (24.23 KiB) Viewed 206 times
Now. If the camera is inside the Volumetric box, causing the missing part of the light beam, the bottom of the Volumetric box need to be above the stage, in order to get the full light beam. But then, the stage will not be visible after rendered.
Interesting eh??

I got your point Fletch, now I am creating only one box, which is the Volumetric box.

x

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Re: Question to Fletch About Volumetric Light Beam

Post by Audiologist » Mon Feb 11, 2019 5:19 pm

Bottom of Volumetric box UNDER the stage
Test 001c.jpg
Test 001c.jpg (116.22 KiB) Viewed 205 times
Bottom of Volumetric ABOVE the stage
Test 001d.jpg
Test 001d.jpg (110.49 KiB) Viewed 205 times

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Re: Question to Fletch About Volumetric Light Beam

Post by Fletch » Mon Feb 11, 2019 5:25 pm

Yes. Makes sense. Build as shown in my example provided in .skp file above and there will be no problem.
As stated in original thread - your volumetric box must be built to be slightly inside of the volume of the space. ... as you have now confirmed for yourself here.

Good to see experimentation. :^:

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Re: Question to Fletch About Volumetric Light Beam

Post by Audiologist » Tue Feb 12, 2019 10:19 am

Fletch, thank you so much for guiding me through this period. Really really appreciated.

Des
Light Beam Test 04.jpg
Light Beam Test 04.jpg (1 MiB) Viewed 196 times

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Re: Question to Fletch About Volumetric Light Beam

Post by Audiologist » Tue Feb 12, 2019 5:16 pm

Fletch wrote:
Mon Feb 11, 2019 5:25 pm

As stated in original thread - your volumetric box must be built to be slightly inside of the volume of the space.
This is the part which made me confused and build two boxes. :lol: :lol:

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