Render Target CAM environment Tweet

[allenh]

Hi there;

What is the "CAM Environment" setting on the Octane Render Target node meant to do?

I ask because it seems like it might be meant for using a backplate (such as a live-action image sequence) mapped to the camera, for compositing or reflection/refraction purposes, but when I try doing this, the result looks stretched and distorted as though it is being mapped to an infinitely-large env sphere rather than to the camera's FOV. Basically, it seems interchangeable with the TEXT Environment tab, and I'm curious if I'm just misunderstanding something.

What I ultimately would like to do is use my live-action plate as a refraction background, but I'm unsure how to accomplish that.

Thanks!

[allenh]

From what I can gather poking around other sites, it seems that my experience is working as intended (which is to say: this parameter seems intended for use with a second ENV map, rather than a 2d backplate).

I'm curious, then, how I might accomplish what I WANT to do (which, again, is having an environment texture of my live-action plate). I know I can map it onto a piece of geometry in my scene, but I'd love to have a more graceful way of handling this.

[fantome]

cam env is when you want to have a secondary env map for your reflections / refractions.
it excpect a latlong coord 360 env map.
for what you want to do. i would create a plane and parent it to my cam then scale it so that it always match and follow the field of view of your cam. then i would use a universal material, disable diffuse / specular and plug my backplate in the emission slot. and i would use that to reflect and refract my backplate.

[juanjgon]

You can also use an OSL shader:
viewtopic.php?f=101&t=71924&p=397039&hilit=backplate+osl#p397039

Thanks,
-juanjo

[allenh]

Hey juanjo;

I actually tried exactly this, in fact! But I was doing so inside the renderTarget node itself, and the OSL did not seem to work. Perhaps – at the point that code is running – there is not yet a render camera context (or something?)

I can definitely create physical geometry that 'rides' with the camera frustum and uses OSL NDC shading; I'd just hoped for something a bit more elegant.

In any case, thanks!