[Fogbugz # 1365098] correct depth transparent lens flare (#5658)

* Binding correct depth for lens flare. Depth bound was depth pyramid causing occlusion artifacts on depth transparent

* Changelog

Co-authored-by: sebastienlagarde <[email protected]>

Author: kecho

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

@@ -46,6 +46,7 @@ and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.
 - Fixed a warning when enabling tile/cluster debug.
 - Fix recursive rendering transmittance over the sky (case 1323945).
 - Fixed specular anti aliasing for layeredlit shader.
+- Fixed lens flare occlusion issues with transparent depth. It had the wrong depth bound (1365098)
 
 ### Changed
 - Visual Environment ambient mode is now Dynamic by default.

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

@@ -513,7 +513,7 @@ TextureHandle RenderPostProcess(RenderGraph renderGraph,
                 // HDRP to reduce the amount of resolution lost at the center of the screen
                 source = PaniniProjectionPass(renderGraph, hdCamera, source);
 
-                source = LensFlareDataDrivenPass(renderGraph, hdCamera, source);
+                source = LensFlareDataDrivenPass(renderGraph, hdCamera, source, depthBuffer);
 
                 TextureHandle bloomTexture = BloomPass(renderGraph, hdCamera, source);
                 TextureHandle logLutOutput = ColorGradingPass(renderGraph, hdCamera);
@@ -3061,11 +3061,12 @@ class LensFlareData
         {
             public LensFlareParameters parameters;
             public TextureHandle source;
+            public TextureHandle depthBuffer;
             public HDCamera hdCamera;
             public Vector2Int viewport;
         }
 
-        TextureHandle LensFlareDataDrivenPass(RenderGraph renderGraph, HDCamera hdCamera, TextureHandle source)
+        TextureHandle LensFlareDataDrivenPass(RenderGraph renderGraph, HDCamera hdCamera, TextureHandle source, TextureHandle depthBuffer)
         {
             if (m_LensFlareDataDataDrivenFS && !LensFlareCommonSRP.Instance.IsEmpty())
             {
@@ -3075,6 +3076,7 @@ TextureHandle LensFlareDataDrivenPass(RenderGraph renderGraph, HDCamera hdCamera
                     passData.parameters = PrepareLensFlareParameters(hdCamera);
                     passData.viewport = postProcessViewportSize;
                     passData.hdCamera = hdCamera;
+                    passData.depthBuffer = depthBuffer;
                     TextureHandle dest = GetPostprocessUpsampledOutputHandle(renderGraph, "Lens Flare Destination");
 
                     builder.SetRenderFunc(
@@ -3083,6 +3085,8 @@ TextureHandle LensFlareDataDrivenPass(RenderGraph renderGraph, HDCamera hdCamera
                             float width = (float)data.viewport.x;
                             float height = (float)data.viewport.y;
 
+                            ctx.cmd.SetGlobalTexture(HDShaderIDs._CameraDepthTexture, data.depthBuffer);
+
                             LensFlareCommonSRP.DoLensFlareDataDrivenCommon(
                                 data.parameters.lensFlareShader, data.parameters.lensFlares, data.hdCamera.camera, width, height,
                                 data.parameters.usePanini, data.parameters.paniniDistance, data.parameters.paniniCropToFit,