Unwrap with UV Cam

Hello,

I am quite new from Notch and I have a question about UV unwrap with the UV CAM.

First of all, let me explain you my project :

I have an angled screen setup (3840 x 1344 px and 90 degree angle) (see attached the screen specifications).

I have a fbx and C4D set up of the screen with a camera for the perfect position.

I made a Notch Animation with a Procedural and Particles system that works perfectly.

I know how to Unwrap my Notch Render (in 4096 x 2048 resolution) with the right camera on After Effect with my UV Map to make a 3844 x 1344 px for the screen.

But I would like to use realtime render animation and to do so I need to unwrap the animation also in realtime in Notch.

Here you can see an image of the “render” and the same image with the right Unwrap made with After Effect (and a video of the animation on the screen) :

https://youtu.be/KU11M9E29xs


Here is a historic of my trials :

  1. I used an precompile node of the “render layer” to apply it as a texture on the fbx with the mapping node and the right cam (I used a proxy camera to be sure to have the same cam that in the render layer). And then I used the UV Cam to Unwrap it.It seems that is working fine but the only problem is that the Unwrapped view is deformed. Indeed, my render needs to be in 4096 x 2048 (2:1 aspect) whereas the final file unwrapped needs to be in 3840 x 1344.

  2. Then, to simplify the workflow and the 2 different resolutions issue (4096 x 2048 for the render and 3844 x 1344 for the unwrap), I simplified my workflow with a unique layer with 2 render to texture. (Layer named “UV CAM Unwrap”)

  3. I also noticed the UV Remap Input in the Image 2D node and I tried to unwrap the render with the same UV Map used in After Effect. It presents the same problem as the UV Cam Unwrap (because of resolution issue). I tried to change the Image 2D’s scale but it doesn’t work as I need a 3840x1344 to output for the screen.

Of course, the UV Cam Solution offers much more possibility. Indeed, if it works, we would be able to change the perfect point of view in real time (the render cam position) and unwrap the new perspective in real time. It would allow us to track a person to change the point of view depending of his position.

I feel like I’m very closed to managed to do it, can you help me with it ?

My DXF file :dl=0DXF File

Thank you by advance and sorry for this looooong post :slight_smile:

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Did you make any progress yet? I would love to help but can’t really figure out where it doesn’t work as expected and the whole after effects workflow.

Maybe you could give an update?

Hello Thomas,

Thank you for your reply.
I didn’t make any progress. I am like really stuck and I tried a lot of things before posting my problem on the forum.

In fact, the understanding of the after effect workflow is not needed, the UV Cam seems to be exactly the right tools to do that in Notch but like I said, I didn’t manage to solve these problems and I still stuck.

I have finaly succeeded !!

As I wanted to send a 3840 x 1344 output (with Spout or NDI) in a player (Resolume for example), the project needs to be in that resolution because it seems like the output need to be in the same resolution as the project.

So first, I changed my project resolution to 3840 x 1344.

I also noticed that the UV Cam wasn’t working well because my UV map wasn’t an square.


After changing it in Blender, it was disformed.

Then, I figured that my “box” wasn’t output straight.


This took me some time to figure out why. In fact, it was because the projection of texture made by the mapping node was in fact flipped (in y). As a consequence, the perspective was right and it made the output box not straight. I just had to change the UV scale Y of the mapping node to -1 (not the material UV scale Y like I first thought).

I am very glad that I managed to solve that problem (It took me a while before understanding why it didn’t work)

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