Body of the Custom Content Pipeline in Office Word

Printer DataMatrix in Office Word Body of the Custom Content Pipeline

Because the input of this content pipeline is an image, you will need to create a custom image processor. This time, however, you cannot inherit from the default image processor, because this requires your processor to produce a TextureContent object. As shown in Figure 5-22, you want to output an object of a custom class, TerrainContent. In this custom processor, you will create an object of a custom class, so you will want to go through the ten short initialization steps of recipe 4-15. In step 4, you will indicate you re going to define a content processor that takes in a TextureContent object and processes this into a TerrainContent object: [ContentProcessor] public class HeightMapProcessor : ContentProcessor<TextureContent, TerrainContent> { public override TerrainContent Process(TextureContent input, ContentProcessorContext context) { } }

After you ve gone through the ten steps, you ll want to add the two custom classes you need in this chapter: the Terrain class containing the code of recipe 5-8 and the TerrainContent class containing all the data required to create a Terrain object from. You can add the first class by importing the class file in your content pipeline project. You will define this last class yourself; for now, add this empty class to your content pipeline project (you ll be adding stuff throughout this recipe): public class TerrainContent { public TerrainContent() { } } With a custom class defined, you need to define a TypeWriter capable of serializing objects of your custom class to a binary file. Add this TypeWriter class to your pipeline project: [ContentTypeWriter] public class CPTerrainTypeWriter : ContentTypeWriter<TerrainContent> { protected override void Write(ContentWriter output, TerrainContent value) { } public override string GetRuntimeReader(TargetPlatform targetPlatform) { return typeof(TerrainTypeReader).AssemblyQualifiedName; } } The first line indicates this class will be a TypeWriter, capable of serializing a TerrainContent object to file. In your Write method, you will define how this should be done. The GetRuntimeReader is called at runtime and informs XNA which TypeReader should be called to deserialize the binary data. However, unlike in recipes 4-15 and 4-16 and as explained in the introduction to this recipe, this time you do not want the binary data to be deserialized into a TerrainContent object but into an object of the Terrain class! You can inform XNA of this by overriding the GetRuntimeType method in your TypeWriter class as well: public override string GetRuntimeType(TargetPlatform targetPlatform) { return typeof(Terrain).AssemblyQualifiedName; } This informs XNA that any data that was serialized from the TerrainContent object should be used to generate a Terrain object at runtime. You are responsible for making your TerrainContent object serialize enough data so a Terrain object can be constructed from it.

With the body of the content pipeline defined, you re ready to update the processor. It is responsible for calculating all the data you want to be stored in the TerrainContent object, starting from a TextureContent object. Change the Process method to this so it calculates all height data, vertices, and indices for the terrain: public override TerrainContent Process(TextureContent input, ContentProcessorContext context) { TextureContent usualImage = context.Convert<TextureContent, TextureContent>(input, "TextureProcessor"); usualImage.ConvertBitmapType(typeof(PixelBitmapContent<Color>)); PixelBitmapContent<Color> image = (PixelBitmapContent<Color>)usualImage.Faces[0][0]; float[,] heightData = HeightMapToArray(image); VertexPositionNormalTexture[] vertices = CreateTerrainVertices(heightData); int[] indices = CreateTerrainIndices(heightData); vertices = GenerateNormalsForTriangleStrip(vertices, indices); }

As good practice (but optional in this case), you first process the image using the default image processor. Next, you convert it to a more usable format and retrieve the only face of interest, as explained in recipe 3-9. Once you know the colors of the individual pixels, you can create all required vertices and indices using the terrain generation code explained in recipe 5-8. This processing code is the main topic of recipe 5-8, so I will not list it here, but remember that now this code will be executed only once at compile time instead of each time at runtime as in recipe 5-8, bringing a speedup at runtime. At this moment, you have virtually everything you need to create a Terrain object. However, keep in mind you re writing a custom content pipeline, so the data first needs to be serialized to a binary file and deserialized by the TypeReader at runtime. Therefore, you need to think about which data you ll need in the TypeReader to generate a Terrain object.