Portal lights

Forums: Portal lights
Newtek Lightwave 3D (exporter developed by holocube, Integrated Plugin developed by juanjgon)

Moderator: juanjgon

Portal lights

Postby alexos » Tue Dec 03, 2013 9:21 am

alexos Tue Dec 03, 2013 9:21 am
I don't get them. The manual says they're geometry - but how do I tell Octane to use my geometry as a portal light? And conversely, what's the light type-portal for? If I add one all settings are ghosted and, in my scene, it doesn't seem to do anything much. What am I missing here?

ADP.
alexos
Licensed Customer
Licensed Customer
 
Posts: 58
Joined: Tue Mar 12, 2013 1:55 pm

Re: Portal lights

Postby UnCommonGrafx » Tue Dec 03, 2013 11:22 am

UnCommonGrafx Tue Dec 03, 2013 11:22 am
It gives the render a "path" through which it can render a window or other such hole in some geometry. Makes the engine, I surmise, not have to figure out how to get/read rays through geometry making it work more efficiently.
Nodally, I tend to mix a portal and the material I want to show on the wall. In this way, I get the look and the more efficient effort of the render engine.
i7-4770K, 32gb ram, windows 8.1, GTX Titan and gt 620 for display
UnCommonGrafx
Licensed Customer
Licensed Customer
 
Posts: 199
Joined: Wed Mar 13, 2013 9:14 pm

Re: Portal lights

Postby alexos » Tue Dec 03, 2013 4:49 pm

alexos Tue Dec 03, 2013 4:49 pm
Hmm, then the "portal" light type is indeed useless?

ADP.
alexos
Licensed Customer
Licensed Customer
 
Posts: 58
Joined: Tue Mar 12, 2013 1:55 pm

Re: Portal lights

Postby juanjgon » Tue Dec 03, 2013 4:55 pm

juanjgon Tue Dec 03, 2013 4:55 pm
There is a material to define any geometry as portal lights. They work only with path tracing or PMC kernels. Anyway I never use them, so I am not sure about it's performance.

-Juanjo
User avatar
juanjgon
Octane Plugin Developer
Octane Plugin Developer
 
Posts: 8867
Joined: Tue Jan 19, 2010 12:01 pm
Location: Spain

Re: Portal lights

Postby Rob49152 » Mon Dec 09, 2013 7:50 pm

Rob49152 Mon Dec 09, 2013 7:50 pm
I've found the portal light to be very useful. In one scene I did I used a sligtly curved surface with an image mapped to it outside of a window. Of course this alone did not give me the lighting I required. So I used the Sky render target and set it up to match the colour and approximate angle of the sun that I needed.

Since I used an image mapped to a polygon outside the window this blocked the sky render target. So I added the light portal to a surface the same shape at the window (an archway) placed it just i bit infront of the window facing inside and tada skylight flooding into the room.

worked perfectly. I also imagine that rendering light through a large glass surface would have slown the render down quite a bit.
CPU: 2x E5-2687W (2x 8 cores + HT = 32 threads @ 3.2GHz+) MOBO: ASUS Z9PE-D8 WS OS:Win7 Ult
RAM: 64gb HD:Revo 3 x2, 240 OCZ SSD, 4TB WD BLACK Website: http://www.interocitor-media.com/tardis
Rob49152
Licensed Customer
Licensed Customer
 
Posts: 51
Joined: Tue Mar 12, 2013 12:23 am
Location: Saskatoon, Sk, Canada

Return to Lightwave 3D


Who is online

Users browsing this forum: Bing [Bot] and 11 guests

Fri Mar 29, 2024 11:39 am [ UTC ]