[Insight-users] DRR raycasting transformation coordinate direction

[MedVision]

Hi all,

   I have questions about the coordinate direction in DRR generation according to the DigitallyReconstructedRadiograph1.cxx example. The alteration of DRRs generated with different transformation parameters are not along the way I expected. 
   The DRR moves as if the volume data is moving along -Tx, +Ty, -Tz direction, and rotaing along -Rx, +Ry, +Rz axis, which does not define a right-handed coordinate. Should the simulated image generated be flipped when compared to the real image since it is said that images in ITK are flipped along the Y axis?
   My understanding is that according to the example, I am seeing from the screen to the focalpoint which are fixed, i.e. along the -Z direction, and the transform should be applied to the volume data. Is that right?  And however, in the example program it is noted: "translation parameter of the camera" and "Rotation around x,y,z axis in degrees", I'm wondering whether it is the transformation of the volume or the camera. Does anyone know what my problems could be? 

   Thanks and Regards

watermark