Fron Projection from Camera

[Pionier]

Hello,

I wasn't quite checking latest news but I wanted to know if Front Projection from the camera is finally working in Vray?

I'm doing the project when 3D needs to be added to photography, so I re-created environment with some low-poly meshes. Then I wanted to project background image itself back to this mesh to get the reflection of the environment on my main object in the scene. That's the basic idea.

At the moment looks like is not possible, the texture is showing on top of the whole render, which gives the similar result to apply it on photoshop with low opacity level.

If I am right, when that will be fixed?
If I am wrong, what is the right way of doing it?

Thanks,
Peter.

[vladimir.nedev]

Front projection works only for the render camera, no improvement there yet.
But it sounds like this is what you need in this case ?

Have you considered using a shadow catcher / matte material on the low poly objects ?

Maybe attach or send a scene, so I can check the exact setup.

Greetings,
Vladimir Nedev

[boyan]

Hey Peter,

Thank you for the post. I've made a simple scene and some tests, as attached files. It seems a bit tricky but I think is a workable solution. Only one note, paint the texture and save it immediately.



camera_projection_test.zip

BR Boyan

Edit : Also be sure that option "Override MODO projection camera" is enabled. You can find it on the "Camera effect" tab -> Vray Camera Type Overrides.

[Pionier]

Hi Vladimir and Boyan,

thanks for taking your time to answer me.

Boyan, If I good understood you, what you are suggesting is to bake texture from camera projection and use it again as a regular texture? That is indeed my idea so far, a little bit of more clicking but it should work.

Vladimir, I attached two images to help illustrate my point. It's exactly the same scene and setup between them. I only apply Vray Materials in Vray scene, rest is the same. You can see that the texture is showing through the diffuse object.

But it may be, I'm doing it wrong?

Thanks,
Peter.

[boyan]

Hey Peter,

Thank's for the post. I think that have a solution about it. Go to Shader tab -> Environment and disable options "Visible to Reflection & Refraction". Also, let to change the channel name of texture layer from "Diffuse color" to "vmtl Diffuse color" . I've added and some ref. as attached files.



camera_projection_test2.zip

BR Boyan

[vladimir.nedev]

You can see that the texture is showing through the diffuse object. But it may be, I'm doing it wrong?

No, you are not doing it wrong. It is a bug that will be fixed together with the support for projection from any camera.
Currently the projection is a very simple "screen" projection, so it doesn't work correctly for secondary rays (reflection /GI).

Also, let to change the channel name of texture layer from "Diffuse color" to "vmtl Diffuse color"

This will have an effect only when rendering with the MODO renderer.
For V-Ray for MODO Diffuse color to vmtl Diffuse color are exactly the same thing.

Greetings,
Vladimir Nedev

[Pionier]

Hi guys,

thanks again for your time,
if this is the case, the way around will be baking projection to regular texture and re-apply it on the model, this should work in Vray!

can't wait for the full support for camera projection then

best,
P.

[vladimir.nedev]

No, you are not doing it wrong. It is a bug that will be fixed together with the support for projection from any camera.
Currently the projection is a very simple "screen" projection, so it doesn't work correctly for secondary rays (reflection /GI).

This has been fixed for some time (including in the official 3.52.01 build).
There are some additional bug fixes to it in the 2017.07.13 nightly build, as well as proper RT updates in the 2017.07.14 nightly build.

Greetings,
Vladimir Nedev