From cbc7c606a636895846a8e1f90d06de70e0dee564 Mon Sep 17 00:00:00 2001
From: myliu <201916234@mail.sdu.edu.cn>
Date: Thu, 5 Nov 2020 19:36:09 +0800
Subject: [PATCH] The position of the wire is taken as the center of the cell.

---
 Detector/DetSegmentation/src/GridDriftChamber.cpp | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/Detector/DetSegmentation/src/GridDriftChamber.cpp b/Detector/DetSegmentation/src/GridDriftChamber.cpp
index b65edb2d..c9cb9d50 100644
--- a/Detector/DetSegmentation/src/GridDriftChamber.cpp
+++ b/Detector/DetSegmentation/src/GridDriftChamber.cpp
@@ -79,9 +79,10 @@ void GridDriftChamber::cellposition(const CellID& cID, TVector3& Wstart,
   updateParams(layerIndex);
 
   double phi_start = phi(cID);
-  double phi_end = phi_start + returnAlpha();
+  double phi_mid = phi_start + _currentLayerphi/2.;
+  double phi_end = phi_mid + returnAlpha();
 
-  Wstart = returnWirePosition(phi_start, -1);
+  Wstart = returnWirePosition(phi_mid, -1);
   Wend = returnWirePosition(phi_end, 1);
 }
 
-- 
GitLab