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Projector

Posted: Sat Sep 06, 2014 12:15 am
by zackyd
I am trying to create an actual projector in Octane. I would do this in C4D with a image in the transparency channel in front of the light. I am failing to achieve this by putting an image in the opacity channel as it is only for grayscale, Anyone have any advice on this?

Re: Projector

Posted: Sat Sep 06, 2014 5:50 am
by bepeg4d
hi,
funny, i was playing yesterday with a projector.
my approach, was to re-create a repro-camera, basically a box with a little hole that works like a thin-lens. then there is a plane with the normal pointing to the hole and a diffuse material with texture emission active. i have prepared a simple xpresso for controlling the aperture and the distance of the emitter from the hole and it works pretty well ;)
if you want i can share the file, it's not perfect but it works ;)
ciao beppe

Re: Projector

Posted: Sat Sep 06, 2014 6:50 pm
by aoktar
also, you can use arealight well.

Re: Projector

Posted: Wed Sep 10, 2014 3:18 pm
by gueoct
Try this method; it´s much faster and more precise:

http://render.otoy.com/forum/viewtopic. ... 54#p202254

Re: Projector

Posted: Wed Sep 10, 2014 3:26 pm
by aoktar
no need all this tricks. Just use a image on arealight's material. try spherical projections or others. i can't remember well which was good, but i did same with a light recently

Re: Projector

Posted: Thu Sep 11, 2014 4:03 am
by zackyd
Aoktar, could you please get together an example using a light? I am unable to get anything close with putting the texture into the light.

Re: Projector

Posted: Fri Sep 12, 2014 2:15 am
by aoktar
it's here

Re: Projector

Posted: Fri Sep 12, 2014 5:02 am
by zackyd
wow... thank you Aoktar. :)

Re: Projector

Posted: Wed Dec 10, 2014 11:47 am
by nikolas
Hello, I've downloaded your zipped file. But: I can't rotate the projected pattern. How can I rotate for animated light for example?
Thank you.

Re: Projector

Posted: Wed Jan 28, 2015 4:51 am
by KHENSU
Hello aoktar,

Thank you for the file. I sometimes get a distorted projected image which bends larger out to the sides from the center (kind of like a pin distortion) when I load a new image in place of your colored grid which projects undistorted. Is there some way to keep the projected image from being distorted? I've tried selecting "Cylinder', Sphere" etc but get the same result.

Thank you in advance