Added proper error messages for "ExportSkyToTexture" to the method.

Assets/ScriptableRenderPipeline/HDRenderPipeline/Editor/HDRenderPipelineMenuItems.cs

             Texture2D result = renderpipelineInstance.ExportSkyToTexture();
             if(result == null)
             {
-                Debug.LogError("Cannot export sky to an image, Sky is not setup properly.");
                 return;
             }
 

Assets/ScriptableRenderPipeline/HDRenderPipeline/HDRenderPipeline.cs

 
         public Texture2D ExportSkyToTexture()
         {
-            return m_SkyManager.ExportSkyToImage();
+            return m_SkyManager.ExportSkyToTexture();
         }
 
         void RenderForward(CullResults cullResults, Camera camera, ScriptableRenderContext renderContext, bool renderOpaque)

Assets/ScriptableRenderPipeline/HDRenderPipeline/Sky/SkyManager.cs

             }
         }
 
-        public Texture2D ExportSkyToImage()
+        public Texture2D ExportSkyToTexture()
-            if(m_Renderer != null && m_Renderer.IsSkyValid())
+            if(m_Renderer == null)
-                int resolution = (int)m_SkySettings.resolution;
+                Debug.LogError("Cannot export sky to a texture, no SkyRenderer is setup.");
+                return null;
+            }
-                RenderTexture tempRT = new RenderTexture(resolution * 6, resolution, 0, RenderTextureFormat.ARGBHalf, RenderTextureReadWrite.Linear);
-                tempRT.dimension = TextureDimension.Tex2D;
-                tempRT.useMipMap = false;
-                tempRT.autoGenerateMips = false;
-                tempRT.filterMode = FilterMode.Trilinear;
-                tempRT.Create();
+            if(m_SkySettings == null)
+            {
+                Debug.LogError("Cannot export sky to a texture, no Sky settings are setup.");
+                return null;
+            }
-                Texture2D temp = new Texture2D(resolution * 6, resolution, TextureFormat.RGBAFloat, false);
-                Texture2D result = new Texture2D(resolution * 6, resolution, TextureFormat.RGBAFloat, false);
+            int resolution = (int)m_SkySettings.resolution;
-                // Note: We need to invert in Y the cubemap faces because the current sky cubemap is inverted (because it's a RT)
-                // So to invert it again so that it's a proper cubemap image we need to do it in several steps because ReadPixels does not have scale parameters:
-                // - Convert the cubemap into a 2D texture
-                // - Blit and invert it to a temporary target.
-                // - Read this target again into the result texture.
-                int offset = 0;
-                for (int i = 0; i < 6; ++i)
-                {
-                    Graphics.SetRenderTarget(m_SkyboxCubemapRT, 0, (CubemapFace)i);
-                    temp.ReadPixels(new Rect(0, 0, resolution, resolution), offset, 0);
-                    temp.Apply();
-                    offset += resolution;
-                }
+            RenderTexture tempRT = new RenderTexture(resolution * 6, resolution, 0, RenderTextureFormat.ARGBHalf, RenderTextureReadWrite.Linear);
+            tempRT.dimension = TextureDimension.Tex2D;
+            tempRT.useMipMap = false;
+            tempRT.autoGenerateMips = false;
+            tempRT.filterMode = FilterMode.Trilinear;
+            tempRT.Create();
+
+            Texture2D temp = new Texture2D(resolution * 6, resolution, TextureFormat.RGBAFloat, false);
+            Texture2D result = new Texture2D(resolution * 6, resolution, TextureFormat.RGBAFloat, false);
+
+            // Note: We need to invert in Y the cubemap faces because the current sky cubemap is inverted (because it's a RT)
+            // So to invert it again so that it's a proper cubemap image we need to do it in several steps because ReadPixels does not have scale parameters:
+            // - Convert the cubemap into a 2D texture
+            // - Blit and invert it to a temporary target.
+            // - Read this target again into the result texture.
+            int offset = 0;
+            for (int i = 0; i < 6; ++i)
+            {
+                Graphics.SetRenderTarget(m_SkyboxCubemapRT, 0, (CubemapFace)i);
+                temp.ReadPixels(new Rect(0, 0, resolution, resolution), offset, 0);
+                temp.Apply();
+                offset += resolution;
+            }
-                // Flip texture.
-                // Temporarily disabled until proper API reaches trunk
-                //Graphics.Blit(temp, tempRT, new Vector2(1.0f, -1.0f), new Vector2(0.0f, 0.0f));
-                Graphics.Blit(temp, tempRT);
+            // Flip texture.
+            // Temporarily disabled until proper API reaches trunk
+            //Graphics.Blit(temp, tempRT, new Vector2(1.0f, -1.0f), new Vector2(0.0f, 0.0f));
+            Graphics.Blit(temp, tempRT);
-                result.ReadPixels(new Rect(0, 0, resolution * 6, resolution), 0, 0);
-                result.Apply();
+            result.ReadPixels(new Rect(0, 0, resolution * 6, resolution), 0, 0);
+            result.Apply();
-                Graphics.SetRenderTarget(null);
-                Object.DestroyImmediate(temp);
-                Object.DestroyImmediate(tempRT);
+            Graphics.SetRenderTarget(null);
+            Object.DestroyImmediate(temp);
+            Object.DestroyImmediate(tempRT);
-                return result;
-            }
-            else
-            {
-                return null;
-            }
+            return result;
         }
     }
 }

Assets/ScriptableRenderPipeline/common/Resources/BlitCubemap.shader

-Shader "Hidden/BlitCubemap" {
+// Note: This shader is supposed to be removed at some point when Graphics.ConvertTexture can take a RenderTexture as a destination (it's only used by sky manager for now).
+Shader "Hidden/BlitCubemap" {
     SubShader {
         // Cubemap blit.  Takes a face index.
         Pass {