Question: How do I remove HDRP from a Unity project?

Answer

Removing the High Definition Render Pipeline (HDRP) from a Unity project involves a few steps since HDRP assets and settings are tightly integrated once installed. Here's how you can revert to the standard pipeline or switch to the Universal Render Pipeline (URP):

1. Backup Your Project: Before making any significant changes, always backup your project to avoid losing work.

2. Change Rendering Settings:

   • Go to Edit > Project Settings > Graphics.
   • Under the Scriptable Render Pipeline Settings, remove the HDRP asset if it's assigned.

3. Remove HDRP Package:

   • Open the Package Manager by going to Window > Package Manager.
   • In the list of packages, find "High Definition RP".
   • Click on it and then click the "Remove" button to uninstall HDRP from your project.

4. Revert Material Settings:

   • HDRP changes the materials in your project. You will need to manually change them back to Standard materials or convert them to URP materials if switching to URP.
   • This can be done through the material editor, selecting the shader dropdown, and choosing the desired shader.

5. Check For HDRP Assets:

   • Some assets specific to HDRP might not work correctly after removal. Check your project for any HDRP-specific assets and consider replacing them with standard versions or alternatives.

6. Scan for Shader Errors:

   • Once HDRP is removed, there may be shader errors. You'll need to fix these manually, either by changing the shader or adjusting the material properties.

7. Clean Up Project Files:

   • Sometimes Unity leaves behind some files even after removing the package. Look through your project for any leftover HDRP files in the Project window and remove them.

8. Switch To URP (if needed):

   • If you want to switch to the URP, you should now install the URP package via the Package Manager.
   • Once URP has been added, you will need to create a URP asset (Create > Rendering > Universal Render Pipeline > Pipeline Asset) and assign it in the Graphics settings as mentioned above.

9. Reimport All Assets:

   • Right-click in the Project window and select Reimport All. This can help clean up lingering issues related to the HDRP removal.

10. Resolve Compilation Errors:

    • After removing HDRP and reimporting assets, there may still be compilation errors in scripts or shaders that directly reference HDRP APIs or features. These need to be addressed manually by editing the code.

Remember to test your project thoroughly after these changes as removing HDRP can have widespread effects on project assets, particularly lighting and materials.