Chaos Corona Forum

Chaos Corona for 3ds Max => [Max] I need help! => Topic started by: marioteodoru on 2015-10-28, 06:22:46

Title: video mapping
Post by: marioteodoru on 2015-10-28, 06:22:46
Hello,

i would like to do a video mapping simulation. Project an video on a car, and rotate the camera around the car. I am a newbie in this field, and i read a lot of info about projectors and lenses and perspective, but it kind of confuses me. I don't understand a lot of stuff :(. I would like to ask for help, if you guys are kind enough to explain some stuff to me. My projects it's just a simulation. I doesn't have to be applied later in real life.

So, my question is, If i just use a coronalightmtl, with a texture and 1.0 direction, is this correct? I already tried and it kind of works, but i'm not sure it's what happens in real video mapping. I think what i get it's just the reflection ( i use a car as the geometry to project on to, and it has reflective material). Do i have to model a projector lens?

How do i proceed with this. Does anyone knows a tutorial, or can give me some hints?
Thank you !
Title: Re: video mapping
Post by: romullus on 2015-10-28, 11:03:58
Not sure if i entirely correct understood your question. But if you talking about light projector, then yes, plug image or image sequence into CoronaLight's or CoronaLightMtl's texmap slot and you good to go. But i wouldn't recoment to set directionality at 1.0. First of all it can produce a lot of noise in Corona and second, it's physically incorrect - even lasers don't emmit 100% parallel light beam. Instead make your light source smaller and set directionality at 0.4 - 0.6, that should resemble real life projectors much more.
Title: Re: video mapping
Post by: marioteodoru on 2015-10-28, 23:19:56
Hello,
thank you for your answer.

this is what i'm trying to achive
Title: Re: video mapping
Post by: romullus on 2015-10-29, 10:32:49
Ok, i withdraw my suggestion to use bitmap in CoronaLight's texmap slot - it looks that it's not suitable for this thing at all. However you can do it exactly like in RL: make your light very small and very strong, put a screen (plane) between light and car - you may want to play with distance between screen and light, assign that screen material with diffuse - 0, refraction - 1, ior - 1 and map refraction colour with bitmap you want to project. Alternatively you can use photometric light instead of Corona's one - it has slot for projector map in it.

Also there's third option, which i prefer the most. It's camera mapping - no need to fiddling around with lights, you can project image exactly where you want.
Title: Re: video mapping
Post by: marioteodoru on 2015-10-29, 21:24:20
Than you very much for your answer!

Is using ies lights the same with building an actual projector?.

 
Title: Re: video mapping
Post by: romullus on 2015-10-29, 22:38:56
No, ies lights has almost nothing to do with projectors.
Title: Re: video mapping
Post by: Nekrobul on 2015-10-29, 22:52:25
Actualy ro recive *projektor* effect is better to use something like standart target direct or target spot light with enabled corona shadows.

Tryed this couple of days ago for the cinema interior projekt.
Title: Re: video mapping
Post by: marioteodoru on 2015-10-29, 23:22:49
thank you. i'll try that too