//TODO (CR Sept 2010): same comment as with the ProgressGraphic stuff; the API is unclear
//as to what it is doing (return value) because it's trying to account for the async loading.
/// <summary>
/// Attempts to start loading the overlay data asynchronously, if not already loaded.
/// </summary>
/// <param name="progress">A value between 0 and 1 indicating the progress of the asynchronous loading operation.</param>
/// <param name="message">A string message detailing the progress of the asynchronous loading operation.</param>
/// <returns></returns>
public bool BeginLoad(out float progress, out string message)
{
// update the last access time
_largeObjectData.UpdateLastAccessTime();
// if the data is already available without blocking, return success immediately
//TODO (CR Sept 2010): because unloading the volume involves disposing it, if every operation that uses it
//isn't in the same lock (e.g. lock(_syncVolumeDataLock)) you could be getting a disposed/null volume here.
VolumeData volume = _volume;
if (volume != null)
{
message = SR.MessageFusionComplete;
progress = 1f;
return(true);
}
lock (_syncLoaderLock)
{
message = SR.MessageFusionInProgress;
progress = 0;
if (_volumeLoaderTask == null)
{
// if the data is available now, return success
volume = _volume;
if (volume != null)
{
message = SR.MessageFusionComplete;
progress = 1f;
return(true);
}
_volumeLoaderTask = new BackgroundTask(c => this.LoadVolume(c), false, null)
{
ThreadUICulture = Application.CurrentUICulture
};
_volumeLoaderTask.Run();
_volumeLoaderTask.Terminated += OnVolumeLoaderTaskTerminated;
}
else
{
// TODO (CR Apr 2013): See comment in OnVolumeLoaderTaskTerminated; if the task were not created
// on the UI thread, _volumeLoaderTask could be set to null before hitting this instruction.
if (_volumeLoaderTask.LastBackgroundTaskProgress != null)
{
message = _volumeLoaderTask.LastBackgroundTaskProgress.Progress.Message;
progress = _volumeLoaderTask.LastBackgroundTaskProgress.Progress.Percent / 100f;
}
}
}
return(false);
}
private VolumeData LoadVolume(IBackgroundTaskContext context)
{
// TODO (CR Apr 2013): Ideally, loading and unloading could be done with minimal locking; this way,
// Unload actually has to wait for Load to finish and vice versa. I think a quicker way would be to
// have a _loading field - have this method set it inside the lock, then proceed to do the load,
// then set the _volume field when done. Have Unload check _loading and just return, otherwise set _volume to null.
// Basically, you don't need to lock the entire load operation - you only need to guarantee that multiple loads
// can't occur at once, and that Unload actually unloads it.
// wait for synchronized access
lock (_syncVolumeDataLock)
{
_largeObjectData.Lock();
try
{
// if the data is now available, return it immediately
// (i.e. we were blocked because we were already reading the data)
if (_volume != null)
{
return(_volume);
}
// load the volume data
if (context == null)
{
_volume = VolumeData.Create(_frames);
}
else
{
_volume = VolumeData.Create(_frames, (n, count) => context.ReportProgress(new BackgroundTaskProgress(n, count, SR.MessageFusionInProgress)));
}
// update our stats
_largeObjectData.BytesHeldCount = 2 * _volume.ArrayLength;
_largeObjectData.LargeObjectCount = 1;
_largeObjectData.UpdateLastAccessTime();
// regenerating the volume data takes a few seconds
_largeObjectData.RegenerationCost = LargeObjectContainerData.PresetComputedData;
// register with memory manager
MemoryManager.Add(this);
return(_volume);
}
finally
{
_largeObjectData.Unlock();
}
}
}
private void UnloadVolume()
{
// wait for synchronized access
lock (_syncVolumeDataLock)
{
// dump our data
if (_volume != null)
{
_volume.Dispose();
_volume = null;
}
// update our stats
_largeObjectData.BytesHeldCount = 0;
_largeObjectData.LargeObjectCount = 0;
// unregister with memory manager
MemoryManager.Remove(this);
}
this.OnUnloaded();
}
public VolumeSlice(Volume volume, VolumeSliceArgs sliceArgs, Vector3D imagePositionPatient, float? spacingBetweenSlices = null)
: this(volume.CreateReference(), sliceArgs, imagePositionPatient, spacingBetweenSlices) {}
public void Dispose()
{
if (_volume != null)
{
_volume.OnReferenceDisposed();
_volume = null;
}
}
public VolumeReference(Volume volume)
{
_volume = volume;
_volume.OnReferenceCreated();
}
private static vtkImageData CreateVtkVolume(Volume volume)
{
var vtkVolume = new vtkImageData();
vtkVolume.RegisterVtkErrorEvents();
vtkVolume.SetDimensions(volume.ArrayDimensions.Width, volume.ArrayDimensions.Height, volume.ArrayDimensions.Depth);
vtkVolume.SetOrigin(0, 0, 0);
vtkVolume.SetSpacing(volume.VoxelSpacing.X, volume.VoxelSpacing.Y, volume.VoxelSpacing.Z);
if (volume.BitsPerVoxel == 16)
{
if (!volume.Signed)
{
using (var array = new vtkUnsignedShortArray())
{
array.SetArray((ushort[]) volume.Array, (VtkIdType) volume.ArrayLength, 1);
vtkVolume.SetScalarTypeToUnsignedShort();
vtkVolume.GetPointData().SetScalars(array);
}
}
else
{
using (var array = new vtkShortArray())
{
array.SetArray((short[]) volume.Array, (VtkIdType) volume.ArrayLength, 1);
vtkVolume.SetScalarTypeToShort();
vtkVolume.GetPointData().SetScalars(array);
}
}
}
else if (volume.BitsPerVoxel == 8)
{
if (!volume.Signed)
{
using (var array = new vtkUnsignedCharArray())
{
array.SetArray((byte[]) volume.Array, (VtkIdType) volume.ArrayLength, 1);
vtkVolume.SetScalarTypeToUnsignedChar();
vtkVolume.GetPointData().SetScalars(array);
}
}
else
{
using (var array = new vtkSignedCharArray())
{
array.SetArray((sbyte[]) volume.Array, (VtkIdType) volume.ArrayLength, 1);
vtkVolume.SetScalarTypeToSignedChar();
vtkVolume.GetPointData().SetScalars(array);
}
}
}
else
{
throw new NotSupportedException("Unsupported volume scalar type.");
}
// This call is necessary to ensure vtkImageData data's info is correct (e.g. updates WholeExtent values)
vtkVolume.UpdateInformation();
return vtkVolume;
}
private void UnloadVolume()
{
// wait for synchronized access
lock (_syncVolumeDataLock)
{
// dump our data
if (_volume != null)
{
_volume.Dispose();
_volume = null;
}
// update our stats
_largeObjectData.BytesHeldCount = 0;
_largeObjectData.LargeObjectCount = 0;
// unregister with memory manager
MemoryManager.Remove(this);
}
this.OnUnloaded();
}
private VolumeData LoadVolume(IBackgroundTaskContext context)
{
// TODO (CR Apr 2013): Ideally, loading and unloading could be done with minimal locking; this way,
// Unload actually has to wait for Load to finish and vice versa. I think a quicker way would be to
// have a _loading field - have this method set it inside the lock, then proceed to do the load,
// then set the _volume field when done. Have Unload check _loading and just return, otherwise set _volume to null.
// Basically, you don't need to lock the entire load operation - you only need to guarantee that multiple loads
// can't occur at once, and that Unload actually unloads it.
// wait for synchronized access
lock (_syncVolumeDataLock)
{
_largeObjectData.Lock();
try
{
// if the data is now available, return it immediately
// (i.e. we were blocked because we were already reading the data)
if (_volume != null)
return _volume;
// load the volume data
if (context == null)
_volume = VolumeData.Create(_frames);
else
_volume = VolumeData.Create(_frames, (n, count) => context.ReportProgress(new BackgroundTaskProgress(n, count, SR.MessageFusionInProgress)));
// update our stats
_largeObjectData.BytesHeldCount = 2*_volume.ArrayLength;
_largeObjectData.LargeObjectCount = 1;
_largeObjectData.UpdateLastAccessTime();
// regenerating the volume data takes a few seconds
_largeObjectData.RegenerationCost = LargeObjectContainerData.PresetComputedData;
// register with memory manager
MemoryManager.Add(this);
return _volume;
}
finally
{
_largeObjectData.Unlock();
}
}
}