Merge pull request #1826 from Unity-Technologies/RemoveSkyInLuxMeter

Remove sky in lux meter

com.unity.render-pipelines.high-definition/CHANGELOG.md

 - Fix HDReflectionProbe offset displayed in gizmo different than what is affected.
 - Fix decals getting into a state where they could not be removed or disabled.
 - Fix issue with package upgrading (HDRP resources asset is now versionned to worarkound package manager limitation)
+- Fix lux meter mode - The lux meter isn't affected by the sky anymore
 
 ## [3.1.0-preview]
 

com.unity.render-pipelines.high-definition/HDRP/RenderPipeline/HDRenderPipeline.cs

                 using (new ProfilingSample(cmd, "Clear HDR target", CustomSamplerId.ClearHDRTarget.GetSampler()))
                 {
                     if (hdCamera.clearColorMode == HDAdditionalCameraData.ClearColorMode.BackgroundColor ||
+                        // If the luxmeter is enabled, the sky isn't rendered so we clear the background color
+                        m_DebugDisplaySettings.lightingDebugSettings.debugLightingMode == DebugLightingMode.LuxMeter ||
                         // If we want the sky but the sky don't exist, still clear with background color
                         (hdCamera.clearColorMode == HDAdditionalCameraData.ClearColorMode.Sky && !m_SkyManager.IsVisualSkyValid()) ||
                         // Special handling for Preview we force to clear with background color (i.e black)
                     {
                         Color clearColor = hdCamera.backgroundColorHDR;
+
+                        // We set the background color to black when the luxmeter is enabled to avoid picking the sky color
+                        if (m_DebugDisplaySettings.lightingDebugSettings.debugLightingMode == DebugLightingMode.LuxMeter)
+                            clearColor = Color.black;
+
                         HDUtils.SetRenderTarget(cmd, hdCamera, m_CameraColorBuffer, m_CameraDepthStencilBuffer, ClearFlag.Color, clearColor);
                     }
                 }

com.unity.render-pipelines.high-definition/HDRP/Sky/SkyRenderingContext.cs

                     m_BuiltinParameters.debugSettings = debugSettings;
 
                     skyContext.renderer.SetRenderTargets(m_BuiltinParameters);
-                    // When rendering the visual sky for reflection probes, we need to remove the sun disk if skySettings.includeSunInBaking is false.
-                    skyContext.renderer.RenderSky(m_BuiltinParameters, false, hdCamera.camera.cameraType != CameraType.Reflection || skyContext.skySettings.includeSunInBaking);
+                    
+                    // If the luxmeter is enabled, we don't render the sky
+                    if (debugSettings.lightingDebugSettings.debugLightingMode != DebugLightingMode.LuxMeter)
+                    {
+                        // When rendering the visual sky for reflection probes, we need to remove the sun disk if skySettings.includeSunInBaking is false.
+                        skyContext.renderer.RenderSky(m_BuiltinParameters, false, hdCamera.camera.cameraType != CameraType.Reflection || skyContext.skySettings.includeSunInBaking);
+                    }
                 }
             }
         }