Scene Capture with a Mask?

Development World Creation
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1

Hello, I’m using a “SceneCaptureComponent” to project a Cube onto a screen. I’m hoping there is a way to Mask out the sky. Or, maybe use a volume to only render the Cube without the sky? This is for cinematics, not gameplay.

SceneCapture

The “sceneCaptureComponent” does not seem to have a way to render the Cube with an alpha/transparent background; the camera projects the sky onto the screen or it projects “black.”

If I turn off the Atmosphere, the screen renders “Black” instead of the sky, that is not desirable as well.

SceneCapture1

Is there a way to mask out the sky so the Cube is the only thing projected and everything behind the Cube is Alpha’d out? Hopefully, without C++? Using Stencils, does not seem to be applicable for “SceneCaptureComponent.”

2

Do you need the cube to move or do anything while doing this?

3

Hello, Detach789. Yes, the cube will move and do other stuff.

4

Why not? It definitely should be in there. You just need to set up a post proces material that renders the scene using that stencil for the scene capture.

Anyway.
Explain the end result in detail.

Rendering a cube onto the screen and needing it to animate/rotate like a cube, probably means you just need to use and animate a cube…

5

Hello, may I request a Step By Step with screen grabs? I seem to be doing something wrong.

  1. I Google’d Post Process material. Made a Post Process volume and plugged it into the Rendering Features>Post Process Material Array.
    a. But all I see is the blue sky.
    b. Alternatively, if I plug the Post Process Material into the camera, I see “black” instead of sky.
    c. I do not know how to use the post process material as a stencil, either.

I truly hope you have some time for a Step by Step with screengrabs.

6

I definitely won’t have time for a step by step.

Sencils work via a mesh being assigned to a stencil. In the case of athmosphere which has no mesh, you have to assing everything else to a stencil.

Once thats done, your post process will have to work with the section that isnt assigned to a stencil number to isolate the athmosphere.

Either way, still not sure what it is you need as an end result.

7

Hello, we need something like a green screen effect within a UE scene. I know UE has the ability to simply place a 3D object in front of and HDRI or textured Quad.

  1. The 3D object has to be projected onto a Quad render target so the 3D object will look 2D; as if it were on a flat screen. The 3D object will be animated by hand within Sequencer with key frames. When we press play in Sequencer, the scene capture camera will project the 3D object onto the quad as a flat 2D animation.

  2. Can’t use a movie render to apply to the flat screen cause the colors on the 3D object appear slightly different. If the 3D object is in the same scene as the scene capture camera the color look correct. The 3D object is located in another part of the scene; we just need to remove the sky and make everything that is the sky transparent; similar to a green screen effect.

Photoshop example:

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8

Makes absolutely 0 sense.
You can render it normally without using scene capture or cube maps if all you need is a still image.

Make a sphere with normals on the inside, and apply any texture you need to it (cut to fit the inside of a sphere).

Same idea with a cube map.

Lighting does not matter to the background. If the light for the render is off, fix the light.

Check the skysphere BP as an example of how to do this.

That said, if you want to go nuts figuring the other way out…
For a green screen effect, set a green cube mesh with chromakey color as the background to the item, make sure it doesn’t receive shadows.
Thats all.