Weird reflection from light emitter

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humanunhuman
Posts: 13
Joined: Fri Mar 19, 2021 8:29 am

Weird reflection from light emitter

Post by humanunhuman » Wed Sep 29, 2021 4:48 pm

Hi!

I am trying to use light emitter to light up my chandelier. It is working fine apart from some odd reflections on the wall. I can not figure out why these four bright light spots show up.. They are there even if the light emitters are extremely low. Any suggestions on why they show up and how to get rid of them?

Many thanks!
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Screenshot 2021-09-29 at 17.09.46.png
Screenshot 2021-09-29 at 17.09.46.png (2.05 MiB) Viewed 3935 times

Fletch
Posts: 12895
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Re: Weird reflection from light emitter

Post by Fletch » Wed Sep 29, 2021 9:03 pm

Please share link to the scene for diagnostic.

humanunhuman
Posts: 13
Joined: Fri Mar 19, 2021 8:29 am

Re: Weird reflection from light emitter

Post by humanunhuman » Thu Sep 30, 2021 1:58 pm

Fletch wrote: Wed Sep 29, 2021 9:03 pm Please share link to the scene for diagnostic.
Hi Fletch, thanks for your reply! Sorry, could you please let me know how I share the scene? Thanks a lot!

Fletch
Posts: 12895
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Re: Weird reflection from light emitter

Post by Fletch » Fri Oct 01, 2021 10:00 pm

if the SU scene is zipped, and still too large to share here as an attachment to your post, then zip and upload scene to a file sharing service such as Dropbox and share the link to the file here on this thread, or sent to me via Private Message.

Fletch
Posts: 12895
Joined: Fri Mar 20, 2009 2:41 pm
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Re: Weird reflection from light emitter

Post by Fletch » Sat Oct 02, 2021 2:01 pm

If I were working in this file, to improve performance in SU (not even talking about Twilight yet):

I would first go into SketchUp Styles Tray Pallette and disable extensions, halos, and all other edge sketchyness. I would use the most basic default sketchup style, and be sure to disable profiles and endpoints. All of that slows performance of SU drastically - in my experience.

Next I go to Window>Model Info>Animation and DISABLE the animation of the scene change transition. This will save much time while in normal working mode. Enable it only when critical for presentation.

next - Disable hidden line view

next - Set all curtain Geometry to "Smooth" with the Smooth Tray Pallette and set smooth angle to 70. This will eliminate SU needing to display thousands of edges for no reason. Also, the curtain will now render smooth.

next - set View Style to "Shaded" (Color only, no texture) to speed up display in the viewport.

next - Delete or hide any geometry not effecting your rendering. These objects slow down processing of the geometry to send to Twilight and slow down the rendering.

next - run Purgeall.rb on your models frequently to clean up from unused and empty items in the scene... unused components, textures, styles, etc. THIS OFTEN FIXES MANY RENDERING ARTIFACTS! After Purgeall your file was massively cleaned up. Lost 400MB in file size! :shock:
Untitled-1.png
Untitled-1.png (8.92 KiB) Viewed 3840 times
next - put all your furniture on a layer/tag called "A-Furn" or something, and turn that off when rendering test renderings for lighting. Create other tags/layers for other objects so you can quickly control what is seen/not seen when running test renderings. You can even set up Scenes that only control visibility of your layers like "furniture off" and "furniture on".

next - there's something strange with your downlight/canlights the spot lights appear to be off in the distance in a different part of the model. The model has several "sloppy" things like this in the model that could be causing slow downs and rendering artifacts.

next - exploded the chandelier a few times but not completely in order to try to find the problem. The four stacked lights that are showing on the wall do appear to be related to the chandelier being 4 stacked candles. After exploding and regrouping - I didn't explode the candles, as I wanted to maintain the simple editabilitye of the candle lights as something I can change in one light and they all change. Regardless - in doing this, a whole other candelabra was discovered way off in the distance away from the model. I deleted that second "phantom" candelabra.

For Candleabra candle lights:
Each face of the curving candle flame shape is going to count as a light if you make them into emitter materials, so that's not recommended.
Put a tiny point light inside of each at 40 watts incandes. type
set candle glass flame to material Lamp Glass Matt

Even after all of this, the performance of the scene in SU and in Twilight improved, but still the 4 weird lights remain on the wall. They go away when the candelabra is hidden. So the problem is definitely somewhere in that Candelabra.

Found that the candelabra still has a mysterious emissive surface somewhere but I can't locate exactly what's happening with it. I opened the Twilight Material editor and opened the materials list dropdown menu - at the very top of the list, the emitter materials are listed first. I found one material in the scene had an emitter material applied to it. the material was called ".EMISSIVO4" - I set that material property to Template>Flat material template. Then the 4 lights on the wall disappeared. :^: But I do not know why. :!

Problem still persists with some strange extra bright light coming off the top of the candelabra. :wall:
Check reversed faces - there were some. Checked geometry - deleted some weird geometry in the top "bowl" shape.
test render reveals bright strange light appears to have been fixed.
reduced brightness of spot lights placed inside of each glass candle to 20 watts (originally tried 40 watts and radius of 1mm)
Set Glass for Candle Flames to Template>Translucent>ThinCurtain

Next tip - (on HLS Tab of SketchUp Material Editor - not Twilight Material editor!) reduced saturation of green on the walls and increased the brightness of the green so it is not sooo dark.

Seems to work, link to updated file sent to you via PM. :hat:

ps - try Template>Frosted Glass>Plexiglass for your pink translucent furniture. ;)
pss - try reducing saturation of the gold flow suede material
Attachments
RECEPTION-TWLSupport_Scene 9.jpg
RECEPTION-TWLSupport_Scene 9.jpg (437.22 KiB) Viewed 3840 times
RECEPTION-TWLSupport_Scene 9-dnz.jpg
RECEPTION-TWLSupport_Scene 9-dnz.jpg (267.05 KiB) Viewed 3840 times
RECEPTION-TWLSupport_Scene 12.jpg
RECEPTION-TWLSupport_Scene 12.jpg (312.34 KiB) Viewed 3837 times

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