/// <summary>
/// Initializes a new instance of the <see cref="ExternalReference"/> class.
/// </summary>
/// <param name="fileName">The reference file name.</param>
/// <param name="loaderParams">Loader parameters specifying optional parameters for loading the resource.</param>
public ExternalReference(String fileName, LoaderParameters loaderParams)
{
if (String.IsNullOrEmpty(fileName))
{
throw new ArgumentNullException("Reference file name cannot be null!");
}
_fileName = fileName;
if (loaderParams == null)
{
_loaderParams = LoaderParameters.None;
}
else
{
_loaderParams = loaderParams;
}
}
/// <summary>
/// Loads the asset relative to another asset source. If UseDefaultContent is set to true, and if the asset cannot be found,
/// an attempt to load it from the default content manager will be made.
/// </summary>
/// <typeparam name="T">Type of resource</typeparam>
/// <param name="assetName">Asset name</param>
/// <param name="relativeResource">Relative asset source</param>
/// <param name="parameters">Loader parameters</param>
/// <returns>Loaded asset, if it exists, otherwise null</returns>
/// <exception cref="System.ObjectDisposedException">Thrown if the manager has been disposed</exception>
/// <exception cref="System.ArgumentNullException">Thrown if the asset name is null</exception>
/// <exception cref="System.InvalidCastException">Thrown if the asset to load does not match return type</exception>
/// <exception cref="Tesla.Content.ResourceNotFoundException">Thrown if resource could not be located</exception>
/// <exception cref="System.InvalidOperationException">Thrown if no suitable loader registered to the manager</exception>
/// <exception cref="Tesla.Core.TeslaException">Thrown if loader parameters are not valid.</exception>
public T LoadRelativeTo <T>(String assetName, IResource relativeResource, LoaderParameters parameters)
{
if (_loadedAssets == null)
{
throw new ObjectDisposedException("Content manager is disposed");
}
if (relativeResource == null)
{
throw new ArgumentNullException("Resource to use to locate relative resource cannot be null");
}
if (String.IsNullOrEmpty(assetName))
{
throw new ArgumentNullException("Asset name is not valid");
}
if (parameters == null)
{
parameters = LoaderParameters.None;
}
if (!parameters.ValidateParameters())
{
throw new TeslaException(String.Format("Error importing resource, {0} parameters are invalid.", parameters.GetType()));
}
Object asset;
String fullName = _resourceLocator.GetFullPathRelativeTo(assetName, relativeResource);
IResource resource = null;
//Try the default content first
if (String.IsNullOrEmpty(fullName))
{
if (!_useDefault)
{
throw new ResourceNotFoundException(String.Format("Resource {0} could not be found", assetName));
}
try {
return(Engine.RenderSystemProvider.DefaultContent.LoadRelativeTo <T>(assetName, relativeResource, parameters));
} catch (Exception e) {
throw new ResourceNotFoundException(String.Format("Resource {0} could not be found", assetName), e.InnerException);
}
}
//Get the full name and see if its been loaded, if not try to locate the resource
if (!parameters.OverrideCache && _loadedAssets.TryGetValue(fullName, out asset))
{
if (asset is T)
{
return((T)asset);
}
else
{
throw new InvalidCastException("Load error: Asset to retrieve does not match specified asset type.");
}
}
else
{
resource = _resourceLocator.LocateResource(fullName);
}
Type targetType = typeof(T);
//Find the appropiate resource loader
ResourceLoader loader = _resourceLoaders[resource.Extension, targetType];
if (loader == null)
{
throw new InvalidOperationException(String.Format("Error loading resource, no suitable loader for that {0} extension found.", resource.Extension));
}
//Load the asset
asset = loader.Load(resource, targetType, parameters);
if (!(asset is T))
{
throw new InvalidCastException("Load error: Asset to retrieve does not match specified asset type.");
}
//Cache the asset and return
_loadedAssets[fullName] = asset;
return((T)asset);
}
/// <summary> /// Loads the resource. /// </summary> /// <param name="resource">Resource to load</param> /// <param name="type">Type of resource</param> /// <param name="parameters">Loader parameters</param> /// <returns>Loaded object</returns> public abstract Object Load(IResource resource, Type type, LoaderParameters parameters);
/// <summary>
/// Deserializes the object and populates it from the input.
/// </summary>
/// <param name="input">Savable input</param>
public void Read(ISavableReader input)
{
_fileName = input.ReadString();
_loaderParams = input.ReadSavable <LoaderParameters>();
}
