MainCamera is white in build, UI is drawn on top - in Version 1.4

[kyl3r92]

I got Version 1.4 from UPM. It worked fine in Editor, but in build the image was white, only the UI layer was drawn on top. I created a Dev Build and connected the Frame Debugger, it seems to be very similar to this issue: https://github.com/alelievr/HDRP-UI-Camera-Stacking/issues/18 But adding the Shaders to "always include" didn't fix it for me.

Have a look at: UI Transparency Background Init.shader There is MainTex defined as "2D" but sampled as array:

5 _MainTex("Main Texture", 2D) = "white" {}
13 TEXTURE2D(_MainTex);
52 float4 s = SAMPLE_TEXTURE2D_X_LOD(_MainTex, s_linear_clamp_sampler, uv, 0);

Unity throws an "error" (yellow warning icon though) if I select this shader file. Something about implicit truncation of vector type. If you change SAMPLE_TEXTURE2D_X_LOD to SAMPLE_TEXTURE2D_LOD the error is gone. But the problem is not fixed.

I also tried returning "0.5" for the alpha - that results in my scene being half-visible (but overlayed with 50% white - as expected) But neither 1 nor 0 work perfectly - also expected. 0.01 looks ok for colors, but stuff on UI Camera show a trace over multiple frames... - this is clearly not the right way to fix it. But it helped me pinpoint the problem.

So I changed everything to 2DArray (like it's done in HDRP UI Compositing.shader):

_MainTex("Main Texture", 2DArray) = "white" {}
TEXTURE2D(_MainTex);
SAMPLE_TEXTURE2D_X_LOD(_MainTex, s_linear_clamp_sampler, uv, 0);

That "worked" but the scene was still too bright, didn't look like it's simply overlayed with a white semi-transparent image. Instead it looked like it's gamma instead of linear? So maybe we are close to a fix here: Using "2DArray" (etc.) in the "UI Transparency Background Init.shader" is step one, and step 2 could have to do with linear/gamma color space. But I'm stuck here. Maybe it helps you to reproduce and find the error? I'm using linear color space and I haven't tested with gamma yet.

But I saw the LinearToGammaSpace function in the shader, altering this didn't have an effect for me. Also the Composite function had a commented line where you probably worked on the alpha parts:

    return s;
    // return float4((s.rgb), s.a);

Which may be a hint that I'm not completely on the wrong track here.

For now I "fixed" it now by replacing the 1.4 with 1.2 from here: https://github.com/alelievr/HDRP-UI-Camera-Stacking/releases

[alelievr]

Thanks for the bug report, there is indeed an error in the dimension of the compositing shader, I fixed it in this commit: https://github.com/alelievr/HDRP-UI-Camera-Stacking/commit/e4aad25510fc888a97a0eaf65131a9dff3cb9d87 (version 1.4.1) Can you check if you still have the intensity issue with the fix?

[kyl3r92]

Hi, thank you! Yes that makes sense, as I've read similar stuff while looking for possible solutions - the mainTex basically needed to be forced to a certain size. This at least somehow explains why it worked in the editor but not in build.

I didn't find 1.4.1 in releases and also not via UPM (only 1.4 so far) but I downloaded the whole repo, deleted the "Editor" and "Runtime" Folders and replaced them. The contained package.json says "1.4.1" so this should be the correct version.

I built the game and can confirm it works as expected now - thanks a lot!

[alelievr]

Thanks for checking, I've published the new release on github: https://github.com/alelievr/HDRP-UI-Camera-Stacking/releases/tag/1.4.1