NormalMappingModelProcessor.cs

#region File Description
//-----------------------------------------------------------------------------
// NormalMappingModelProcessor.cs
//
// This file is subject to the terms and conditions defined in file 'LICENSE.txt', which is part of this source code package.
// MonoGame - Copyright (C) The MonoGame Team
//-----------------------------------------------------------------------------
#endregion

#region Using Statements
using Microsoft.Xna.Framework.Content.Pipeline;
using Microsoft.Xna.Framework.Content.Pipeline.Graphics;
using Microsoft.Xna.Framework.Content.Pipeline.Processors;
using System;

#endregion

namespace MonoGame.Tests.ContentPipeline
{
    /// <summary>
    /// The NormalMappingModelProcessor is used to change the material/effect applied
    /// to a model. After going through this processor, the output model will be set
    /// up to be rendered with NormalMapping.fx.
    /// </summary>
    [ContentProcessor(DisplayName = "Normal Mapping Validation")]
    public class NormalMappingModelProcessor : ModelProcessor
    {
        public override ModelContent Process(NodeContent input,
            ContentProcessorContext context)
        {
            if (input == null)
            {
                throw new ArgumentNullException("input");
            }
            context.Logger.LogImportantMessage("processing: " + input.Name);
            PreprocessSceneHierarchy(input, context, input.Name);
            return base.Process(input, context);
        }


        /// <summary>
        /// Recursively calls MeshHelper.CalculateTangentFrames for every MeshContent
        /// object in the NodeContent scene.
        /// </summary>
        /// <param initialFileName="input">A node in the scene.  The function should be called
        /// with the root of the scene.</param>
        private void PreprocessSceneHierarchy(NodeContent input,
            ContentProcessorContext context, string inputName)
        {
            MeshContent mesh = input as MeshContent;
            if (mesh != null)
            {
                MeshHelper.CalculateTangentFrames(mesh,
                    VertexChannelNames.TextureCoordinate(0),
                    VertexChannelNames.Tangent(0),
                    VertexChannelNames.Binormal(0));
            }
        }
    }
}