+ mMapper->SetVolumeRayCastFunction(mRayCastFunction);
+ mMapper->AutoAdjustSampleDistancesOn();
+
+ _volumeProperty = vtkVolumeProperty::New();
+ _volumeProperty->SetInterpolationTypeToLinear();
+ _volumeProperty->ShadeOn();
+ _volumeProperty->DisableGradientOpacityOn();
+ //_volumeProperty->SetColor(_ctfun);
+ //_volumeProperty->SetScalarOpacity(_tfun );