Enable sky IBL

Assets/ScriptableRenderLoop/HDRenderLoop/HDRenderLoop.cs

             //Shader.SetGlobalTexture("_CookieTextures", m_CookieTexArray.GetTexCache());
             //Shader.SetGlobalTexture("_CubeCookieTextures", m_CubeCookieTexArray.GetTexCache());
             Shader.SetGlobalTexture("_EnvTextures", m_CubeReflTexArray.GetTexCache());
+            m_SkyRenderer.SetGlobalSkyTexture();
 
             if (debugParameters.useSinglePassLightLoop)
             {

Assets/ScriptableRenderLoop/HDRenderLoop/Lighting/SinglePass/SinglePassLoop.hlsl

         iblSpecularLighting = lerp(iblSpecularLighting, localSpecularLighting, weight.y);
     }
 
-    /*
+
+        // The EnvLightData of the sky light contains a bunch of compile-time constants.
+        // We set them here directly to allow the compiler to propagate them and optimize the code.
+        _EnvLightSky.envShapeType  = ENVSHAPETYPE_SKY;
+        _EnvLightSky.envIndex      = 0;
+        _EnvLightSky.forward       = float3(0.0, 0.0, 1.0);
+        _EnvLightSky.up            = float3(0.0, 1.0, 0.0);
+        _EnvLightSky.right         = float3(1.0, 0.0, 0.0);
+        _EnvLightSky.positionWS    = float3(0.0, 0.0, 0.0);
+        _EnvLightSky.offsetLS      = float3(0.0, 0.0, 0.0);
+        _EnvLightSky.innerDistance = float3(0.0, 0.0, 0.0);
+        _EnvLightSky.blendDistance = 1.0;
+
-    */
 
     diffuseLighting  += iblDiffuseLighting;
     specularLighting += iblSpecularLighting;

Assets/ScriptableRenderLoop/HDRenderLoop/Sky/SkyRenderer.cs

             }
         }
 
+        // Sets the global "_SkyTexture" cubemap array in the shader.
+        // The texture being set is a sky (environment) map pre-convolved with GGX.
+        public void SetGlobalSkyTexture()
+        {
+            Shader.SetGlobalTexture("_SkyTexture", m_SkyboxGGXCubemapRT);
+        }
+
         public void Rebuild()
         {
             // TODO: We need to have an API to send our sky information to Enlighten. For now use a workaround through skybox/cubemap material...