GPU TPC: Fix using correct cluster errors with all modifiers during refit with TrackParCov model

Author: davidrohr

GPU/GPUTracking/Merger/GPUTPCGMPropagator.cxx

@@ -598,20 +598,25 @@ GPUd() int GPUTPCGMPropagator::GetPropagatedYZ(float x, float& GPUrestrict() pro
 }
 
 GPUd() void GPUTPCGMPropagator::GetErr2(float& GPUrestrict() err2Y, float& GPUrestrict() err2Z, const GPUParam& GPUrestrict() param, float posZ, int iRow, short clusterState, bool sideC) const
+{
+  GetErr2(err2Y, err2Z, param, mT0.GetSinPhi(), mT0.DzDs(), posZ, mT->GetX(), iRow, clusterState, sideC);
+  mStatErrors.GetOfflineStatisticalErrors(err2Y, err2Z, mT0.GetSinPhi(), mT0.DzDs(), clusterState);
+}
+
+GPUd() void GPUTPCGMPropagator::GetErr2(float& GPUrestrict() err2Y, float& GPUrestrict() err2Z, const GPUParam& GPUrestrict() param, float snp, float tgl, float posZ, float x, int iRow, short clusterState, bool sideC)
 {
 #ifndef GPUCA_TPC_GEOMETRY_O2
   if (mSeedingErrors) {
-    param.GetClusterErrorsSeeding2(iRow, posZ, mT0.GetSinPhi(), mT0.DzDs(), err2Y, err2Z);
+    param.GetClusterErrorsSeeding2(iRow, posZ, snp, tgl, err2Y, err2Z);
   } else
 #endif
   {
-    param.GetClusterErrors2(iRow, posZ, mT0.GetSinPhi(), mT0.DzDs(), err2Y, err2Z);
+    param.GetClusterErrors2(iRow, posZ, snp, tgl, err2Y, err2Z);
   }
   param.UpdateClusterError2ByState(clusterState, err2Y, err2Z);
-  float statErr2 = param.GetSystematicClusterErrorIFC2(mT->GetX(), posZ, sideC);
+  float statErr2 = param.GetSystematicClusterErrorIFC2(x, posZ, sideC);
   err2Y += statErr2;
   err2Z += statErr2;
-  mStatErrors.GetOfflineStatisticalErrors(err2Y, err2Z, mT0.SinPhi(), mT0.DzDs(), clusterState);
 }
 
 GPUd() float GPUTPCGMPropagator::PredictChi2(float posY, float posZ, int iRow, const GPUParam& GPUrestrict() param, short clusterState, bool sideC) const

GPU/GPUTracking/Merger/GPUTPCGMPropagator.h

@@ -129,6 +129,7 @@ class GPUTPCGMPropagator
   GPUd() void GetBxByBz(float Alpha, float X, float Y, float Z, float B[3]) const;
 
   GPUd() void GetErr2(float& err2Y, float& err2Z, const GPUParam& param, float posZ, int iRow, short clusterState, bool sideC) const;
+  GPUd() static void GetErr2(float& err2Y, float& err2Z, const GPUParam& param, float snp, float tgl, float posZ, float x, int iRow, short clusterState, bool sideC);
 
   GPUd() float GetAlpha() const { return mAlpha; }
   GPUd() void SetAlpha(float v) { mAlpha = v; }

GPU/GPUTracking/Refit/GPUTrackingRefit.cxx

@@ -374,8 +374,7 @@ GPUd() int GPUTrackingRefit::RefitTrack(T& trkX, bool outward, bool resetCov)
       CADEBUG(printf("\t%21sPropaga Alpha %8.3f    , X %8.3f - Y %8.3f, Z %8.3f   -   QPt %7.2f (%7.2f), SP %5.2f (%5.2f)   ---   Res %8.3f %8.3f   ---   Cov sY %8.3f sZ %8.3f sSP %8.3f sPt %8.3f   -   YPt %8.3f\n", "", trk.getAlpha(), x, trk.getParams()[0], trk.getParams()[1], trk.getParams()[4], trk.getParams()[4], trk.getParams()[2], trk.getParams()[2], trk.getParams()[0] - y, trk.getParams()[1] - z, sqrtf(trk.getCov()[0]), sqrtf(trk.getCov()[2]), sqrtf(trk.getCov()[5]), sqrtf(trk.getCov()[14]), trk.getCov()[10]));
       gpu::gpustd::array<float, 2> p = {y, z};
       gpu::gpustd::array<float, 3> c = {0, 0, 0};
-      mPparam->GetClusterErrors2(currentRow, z, getPar(trk)[2], getPar(trk)[3], c[0], c[2]);
-      mPparam->UpdateClusterError2ByState(clusterState, c[0], c[2]);
+      GPUTPCGMPropagator::GetErr2(c[0], c[2], *mPparam, getPar(trk)[2], getPar(trk)[3], z, x, currentRow, clusterState, sector >= 18);
       TrackParCovChi2 += trk.getPredictedChi2(p, c);
       if (!trk.update(p, c)) {
         IgnoreErrors(trk.getSnp());