Changeset 19664 for trunk

Timestamp:

09/23/19 18:17:17 (5 years ago)

Author:

tbretz

Message:

Added some longer comments on the meaning of some variables, the valid range must be aligned with the pulse width, not Xminand Xmax of the pulse. The pulse is now shifted such that a photon with t=0 (w.r.t. to the simulation sampling window) gets sampled fully into the window

File:

• trunk/Mars/msimcamera/MSimCamera.cc (modified) (3 diffs)

trunk/Mars/msimcamera/MSimCamera.cc

@@ -297 +297 @@
     // FIXME: Should we use a higher sampling here?
 
+    // Start end end of sampling window (in ns, converted to samples)
+    // The sampling window starts at start+pulsewidth to have a potential
+    // previous pulse in the widdow. The trigger should then be at
+    // start+pulsewidth+triggerpos
     const Double_t start = fStat->GetTimeFirst()*freq;
     const Double_t end   = fStat->GetTimeLast() *freq;
 
+    // Length of the simulated window (in units of samples)
+    // nlen = (last-first)+roi+pulsewidth
     const UInt_t   nlen  = TMath::CeilNint(end-start);
 
@@ -313 +319 @@
     }
 
-    const Double_t pl = fSpline->GetXmin()*freq;
-    const Double_t pr = fSpline->GetXmax()*freq;
+    const Double_t pw = fSpline->GetXmax()-fSpline->GetXmin(); // [samples] Width of pulse
 
     // Init the arrays and set the range which will contain valid data
+    // FIXME: There must be some contingency for all the time offsets...
+    // otherwise, we might loose late triggers!!!!!
     fCamera->Init(npix, nlen);
-    fCamera->SetValidRange(TMath::FloorNint(pr), TMath::CeilNint(nlen+pl));
+    fCamera->SetValidRange(TMath::FloorNint(pw), nlen);
 
     Double_t timeoffset[npix];
-
 
     // Add electronic noise to empty channels
@@ -504 +510 @@
         const Double_t gain = (*fGain)[idx].GetPedestal();
 
+        // The "-GetXmin" ensures that a photon at t=0 does not get sampled
+        // before the sampling window!
         // === FIXME === FIXME === FIXME === Frequency!!!!
-        (*fCamera)[idx].AddPulse(*fSpline, t, ph.GetWeight()*gain);
+        (*fCamera)[idx].AddPulse(*fSpline, t - fSpline->GetXmin(), ph.GetWeight()*gain);
     }