ALICE3-TRK: correct shift of VD chips to match the APTS response coordinate system + fix comment

Author: atriolo

Detectors/Upgrades/ALICE3/TRK/simulation/include/TRKSimulation/Digitizer.h

@@ -107,7 +107,7 @@ class Digitizer
   {
     if (subDetID == 0) { // VD
       return constants::VD::petal::layer::nCols;
-    } else if (subDetID == 1) { // ML/OT: the smallest element is a chip of 500 rows and 640 cols
+    } else if (subDetID == 1) { // ML/OT: the smallest element is a chip of 470 rows and 640 cols
       return constants::moduleMLOT::chip::nCols;
     }
     return 0;

Detectors/Upgrades/ALICE3/TRK/simulation/src/Digitizer.cxx

@@ -73,7 +73,7 @@ void Digitizer::init()
 
   mSimRespVDScaleX = o2::trk::constants::apts::pitchX / o2::trk::SegmentationChip::PitchRowVD;
   mSimRespVDScaleZ = o2::trk::constants::apts::pitchZ / o2::trk::SegmentationChip::PitchColVD;
-  mSimRespVDShift = -mChipSimRespVD->getDepthMax(); // the curved, rescaled, sensors have a width from 0 to -45. Must add 10 um (= max depth) to match the APTS response.
+  mSimRespVDShift = mChipSimRespVD->getDepthMax(); // the curved, rescaled, sensors have a width from 0 to -45. Must add 10 um (= max depth) to match the APTS response.
   mSimRespMLOTScaleX = o2::trk::constants::apts::pitchX / o2::trk::SegmentationChip::PitchRowMLOT;
   mSimRespMLOTScaleZ = o2::trk::constants::apts::pitchZ / o2::trk::SegmentationChip::PitchColMLOT;
   mSimRespMLOTShift = mChipSimRespMLOT->getDepthMax() - thicknessMLOT / 2.f; // the shift should be done considering the rescaling done to adapt to the wrong silicon thickness. TODO: remove the scaling factor for the depth when the silicon thickness match the simulated response