first working

[UnityPaul]

Enable Z-Test to optimize overdraw

1. Create a 2D depth buffer at any resolution
2. Upscale the depth buffer to match frame buffer
3. Draw Transparents with depth buffer

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[github-actions]

Hi! This comment will help you figure out which jobs to run before merging your PR. The suggestions are dynamic based on what files you have changed.
Link to Yamato: https://unity-ci.cds.internal.unity3d.com/project/902/
Search for your PR branch using the search bar at the top, then add the following segment(s) to the end of the URL (you may need multiple tabs depending on how many packages you change)

URP
/jobDefinition/.yamato%252Fall-urp.yml%2523PR_URP_trunk
With changes to URP packages, you should also run
/jobDefinition/.yamato%2Fall-lightmapping.yml%23PR_Lightmapping_trunk

Depending on the scope of your PR, you may need to run more jobs than what has been suggested. Please speak to your lead or a Graphics SDET (#devs-graphics-automation) if you are unsure.

[manuele-bonanno]

the DepthOnlyPass.cs change looks good, I didn't look in much detail into the 2D specific changes

[manuele-bonanno]

not sure if this is a temporary change for testing purpose or final. If final you can remove the ternary operator completely and replace it with BuiltinRenderTextureType.None