xml save Texture2D

As some of you’ve might seen, I’ve been breaking my head over the following problem for the past few days:

How do I serialize the class like the following without creating a special ‘intermediate’ struct for each and ever classes

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public class MyData     {         [ContentSerializer(SharedResource = true)]         public Texture2D myTexture;         public int myInt;         public string[] myLines;         public MyData() { } // for deserialization         public MyData(int myInt, Texture2DProxy myTexture, string[] myLines)         {             this.myInt = myInt;             this.myTexture = myTexture;             this.myLines = myLines;         }     }

Even though I’ve marked the Texture2D as a shared resource, I still can’t serialize it using the IntermediateSerializer because a Texture2D always has a reference to a GraphicsDevice object, and the IS can’t serialize that.

Fortunately some helpfull people in #XNA on Efnet (ecosky and flashed, that’s you guys!) told me about proxyclasses, first I was confused and thought they wanted me to write a proxy for every class in my project, but soon they helped me understand that I should write a proxy class for Texture2D. I just had to write a proxy class that can be serialized and that will store the path to texture, so that it can reload itself when deserialized.

I quickly came up with the following class, very simple but it will suffice for now:

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public class Texture2DProxy     {         public Texture2DProxy(string path)         {             LoadTexture(path);         }           public Texture2DProxy() { }           private void LoadTexture(string path)         {             ContentManager content = GameServices.GetService<ContentManager>(); //My own class, see my code snippet, you can also reference a static CM here.             texture = content.Load<Texture2D>(path);             this.path = path;         }           [ContentSerializerIgnore()] //make this is not serialized         private Texture2D texture;           [ContentSerializerIgnore()]         public Texture2D Texture         {             get             {                 if (texture == null)                 {                     LoadTexture(path);                 }                 return texture;             }         }           [ContentSerializer()] //make sure this is, even-though it's a private field.         private string path;     }

Now we just need to replace Texture2D with Texture2DProxy everywhere, and update some code. In the end we can now serialize and deserialize the MyData class like this:

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public void DoSerialize(MyData myData)         {             XmlWriterSettings settings = new XmlWriterSettings();             settings.Indent = true;             using (XmlWriter writer = XmlWriter.Create("example.xml", settings))             {                 IntermediateSerializer.Serialize(writer, myData, null);             }         }           public MyData DoLoad()         {             MyData tmp;             XmlReaderSettings settings = new XmlReaderSettings();             using(XmlReader reader = XmlReader.Create("example.xml", settings))             {                 tmp = IntermediateSerializer.Deserialize<MyData>(reader, null);             }               return tmp;         }

Btw, serializing like this will generate the following XML file:

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<?xml version="1.0" encoding="utf-8"?> <XnaContent>   <Asset Type="XNASerialization.MyData">     <myTexture>#Resource1</myTexture>     <myInt>42</myInt>     <myLines>       <Item>Two households, both alike in dignity,</Item>       <Item>In fair Verona, where we lay our scene,</Item>       <Item>From ancient grudge break to new mutiny,</Item>       <Item>Where civil blood makes civil hands unclean.</Item>     </myLines>   </Asset>   <Resources>     <Resource ID="#Resource1" Type="XNASerialization.Texture2DProxy">       <path>latern</path>     </Resource>   </Resources> </XnaContent>

With this problem out of the way, I can now finally start working on a way to save and restore levels in Hollandia. Oh btw, you can ofcourse do the same trick with SoundEffects and Models or anything else for that matter.