Missing WriteBuffer to support mesh sampling

Author: PaulDemeulenaere

com.unity.visualeffectgraph/Editor/Compiler/VFXCodeGenerator.cs

@@ -367,7 +367,8 @@ internal static void BuildParameterBuffer(VFXContextCompiledData contextData, IE
             var parameterBuffer = new VFXShaderWriter();
             parameterBuffer.WriteCBuffer(contextData.uniformMapper, "parameters");
             parameterBuffer.WriteLine();
-
+            parameterBuffer.WriteBuffer(contextData.uniformMapper, contextData.graphicsBufferUsage);
+            parameterBuffer.WriteLine();
             parameterBuffer.WriteTexture(contextData.uniformMapper, filteredOutTextures);
             parameterBufferContent = parameterBuffer.ToString();
         }