Post Process: How to Absolute World Position at UV

General Feedback & Requests
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1

Hi,

you all know the Absolute World Position (per Pixel) Node.

What i need now is the same thing but at a given UV like SceneTexture Node.

Is this possible? Should i request it?

Thanks and cheers

2

You might be helped by the post right after yours.

How to convert World Position to Screen UV coordinate

Not saying it’s the exact same, but it could have information that is necessary.

3

Hi, i have dived deeper and the solution would be a custom hlsl node that does some interpolation from the vertex shader.

But i am not familiar with hlsl.

Deer Epic Games. Would you mind extending the absolute world position node with an UV input?

Meanwhile i skip my task.

4

What, basically, are you using it for? There isn’t a GetUVCoordinate node or reference type node? It would be valuable, I presume.

5

I have found a solution. Not the best but it does the job for the moment.

This and Custom UV plugged into the Custom Depth or in my case Scene Depth. Thats it.

But an Absolute World Position with an UV Input would be much nicer.

6

Simply to get an absolute world position at UV? UE needs a simpler BP function(s) for that. Do a request. I would, but I don’t know enough about it to describe at length how it would be valuable.

7

Hi, i already did:

https://forums.unrealengine.com/unreal-engine/feedback-for-epic/1695032-material-editor

Why it is valuable for me?: I combine a post process scanner with screen pixelation.
For a post process scanner you have to use the absolute world position per pixel and do some calculations. For a pixelated screen you have to divide the screen into grid cells. Within a grid cell all values shall be the same, for example the value of the middle of that cell. To achieve that you have to “snap” the UV for any values, also absolute world position.

8

I see. So, snapping the UV and doing something in the post process scanner based on abs world position requires being able to utilize the UV at world position…hence the need for a UV input in the World Position node. Then it’s connected in the blueprint, and doesn’t require a bunch of extra connections and math to get the values of UV and abs world pos where they line up, and so forth.

I was thinking how the material editor is quite limiting sometimes in terms of how to combine data points without having to use an extensive workaround that can require more time and effort than if the capacity to do it was already there in a simpler form.