HDRP Transparent Render Target Render Texture

Dear unity Community / Unity Team.

Im in need of a kind of special case withe the HDRP.

I have a project that requires rendering a image of an object / scene with alpha channel in a RenderTexture.
The original project was in unity 2018.2.16 with HDRP 3.0.0-preview and Post Processing 2.0.13-Preview.
The RenderTexture did look like this:
Color:


Alpha:

But in the current HDRP for 2019.1 / 2019.2 the alpha channel is allays just blank.

Is there any way to recreate this result in a current unity / HDRP version?

I do not need camera stacking , i do the compositing with other textures myself.

i got a similar issue, hope anybody can help

Same issue here, no alphachannel in RenderTexture with HDRP (Unity 2019.2.0f1).
Hope this will be fixed, soon!?

Sadly unity does not see it as a problem:

:eyes: that’s really sad! I don’t get it, this was an essential feature for years?!

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As a work around you could render the alpha channel into a separate texture.

Show me how.
The Renderpipline is not rendering the alpha channel at all, so i do not have access to it.

Oh, i thought you were controlling the rendering process.

In this case i think this would require to fiddle with the rendering pipeline code itself, but i haven’t done it so i can’t suggest anything.

This looks like a serious problem for devs if there aren’t any available options to obtain the alpha channel for now, i hope Unity will add such an option in the future.

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