- added new class ZDiskPetalsStruct/ZDiskPetalsData

 - added treatment of gear::FTDParameters (for ILD )

DDRec/include/DDRec/DetectorData.h

 #ifndef DDRec_DetectorData_H_
 #define DDRec_DetectorData_H_
 
+#include <bitset>
 
 namespace DD4hep {
   namespace DDRec {
@@ -145,6 +146,101 @@ namespace DD4hep {
 
 
 
+    /** Simple data structure with key parameters for
+     *  reconstruction of a silicon tracking detector
+     *  with disks (roughly orthogonal to the z-axis) built from petals.
+     *  ( Can be used to instantiate a gear::FTDParameters object )
+     * 
+     * @author F.Gaede, CERN/DESY
+     * @date Oct, 20 2014
+     * @version $Id: $
+     */
+    struct ZDiskPetalsStruct{
+
+      /// width of the strips (if applicable )
+      double widthStrip ;
+      /// length of the strips (if applicable )
+      double lengthStrip ;
+      /// strip pitch  (if applicable )
+      double pitchStrip ;
+      /// strip stereo angle  (if applicable )
+      double angleStrip ;
+      
+      /// enum for encoding the sensor type in typeFlags
+      struct SensorType{
+	enum {
+	  DoubleSided=0,
+	  Pixel
+	};
+      } ;
+
+      /** Internal helper struct for defining the layer layout. Layers are defined 
+       *  with a sensitive part and a support part.
+       */      
+      struct LayerLayout{
+	
+	
+	/// half angle covered by petal 
+	double  petalHalfAngle ;
+	
+	/** angle alpha by which the petal is rotated away from the plane 
+	 *  that is orthogonal to the z-axis 
+	 */
+	double  alphaPetal ;
+	
+	/// z-position of layer ( z-position of middle axis ) 	
+	double  zPosition ;
+
+	/// The number of petals in the layer.
+	int petalNumber ;
+
+ 	/// number of sensor per petal
+	int sensorsPerPetal ;
+
+	/// Bit flag describing sensor type - use enum SensorType to access the bits.
+	std::bitset<32> typeFlags ;
+
+	/// azimuthal angle of vector defined by the Z-axis to first petal x-positive, y-positive edge 
+	double phi0 ; 
+
+	/** z-offset of support petals from layer z-position - signed for first
+	 *  petal, following petals have alternating sign 
+	 */
+	double  zOffsetSupport ;
+	/// The distance of the petal support from the z-axis.
+	double distanceSupport ;
+	/// The thickness of the petal support.
+	double thicknessSupport ;
+	/// The inner width of the petal support.
+	double widthInnerSupport ;
+	/// The outer width of the petal support.
+	double widthOuterSupport ;
+	/// The radial length of the petal support.
+	double lengthSupport ;
+
+	/** z-offset of sensitive petals from layer z-position - signed for first
+	 *  petal, following petals have alternating sign 
+	 */
+	double  zOffsetSensitive ;
+	/// The distance of the petal sensitive from the z-axis.
+	double distanceSensitive ;
+	/// The thickness of the petal sensitive.
+	double thicknessSensitive ;
+	/// The inner width of the petal sensitive.
+	double widthInnerSensitive ;
+	/// The outer width of the petal sensitive.
+	double widthOuterSensitive ;
+	/// The radial length of the petal sensitive.
+	double lengthSensitive ;
+      } ;
+
+      std::vector<LayerLayout> layers ;
+
+    } ;
+    typedef StructExtension<ZDiskPetalsStruct> ZDiskPetalsData ;
+
+
+
 
   } /* namespace DDRec */
 } /* namespace DD4hep */

DDRec/src/gear/createGearForILD.cpp

@@ -8,6 +8,7 @@
 #include "gearimpl/TPCParametersImpl.h"
 #include "gearimpl/FixedPadSizeDiskLayout.h"
 #include "gearimpl/ZPlanarParametersImpl.h"
+#include "gearimpl/FTDParametersImpl.h"
 
 #include <iostream>
 
@@ -145,6 +146,52 @@ namespace DD4hep{
       setDE.addExtension< GearHandle >( new GearHandle( gearSET, "SETParameters" ) ) ;
      //============================================================================================
 
+      DetElement ftdDE = lcdd.detector("FTD") ;
+      
+      ZDiskPetalsData* ftd = ftdDE.extension<ZDiskPetalsData>() ;
+      
+      gear::FTDParametersImpl* gearFTD = new gear::FTDParametersImpl();
+      
+      for(unsigned i=0,n=ftd->layers.size() ; i<n; ++i){
+	
+	const DDRec::ZDiskPetalsData::LayerLayout& l = ftd->layers[i] ;
+	
+
+	bool isDoubleSided  = l.typeFlags[ DDRec::ZDiskPetalsStruct::SensorType::DoubleSided ] ;
+	int  sensorType   = ( l.typeFlags[ DDRec::ZDiskPetalsStruct::SensorType::Pixel ] ?
+			      gear::FTDParameters::PIXEL :  gear::FTDParameters::STRIP ) ;
+
+	double zoffset = fabs( l.zOffsetSupport ) ;
+	double signoffset =  l.zOffsetSupport > 0  ?  1. : -1 ;
+	
+	gearFTD->addLayer( l.petalNumber, l.sensorsPerPetal, 
+			   isDoubleSided, sensorType, 
+			   l.petalHalfAngle, l.phi0, l.alphaPetal, 
+			   l.zPosition/dd4hep::mm, zoffset/dd4hep::mm, signoffset,
+			   l.distanceSupport/dd4hep::mm, l.thicknessSupport/dd4hep::mm,
+			   l.widthInnerSupport/dd4hep::mm, l.widthOuterSupport/dd4hep::mm,
+			   l.lengthSupport/dd4hep::mm, 
+			   0.,
+			   l.distanceSensitive/dd4hep::mm, l.thicknessSensitive/dd4hep::mm,
+			   l.widthInnerSensitive/dd4hep::mm, l.widthOuterSensitive/dd4hep::mm,
+			   l.lengthSensitive/dd4hep::mm, 
+			   0. ) ;
+	
+
+	// FIXME set rad lengths to 0 -> need to get from DD4hep ....
+      }
+     
+      gearFTD->setDoubleVal("strip_width_mm"  , ftd->widthStrip / dd4hep::mm ) ;
+      gearFTD->setDoubleVal("strip_length_mm" , ftd->lengthStrip/ dd4hep::mm ) ;
+      gearFTD->setDoubleVal("strip_pitch_mm"  , ftd->pitchStrip / dd4hep::mm ) ;
+      gearFTD->setDoubleVal("strip_angle_deg" , ftd->angleStrip / dd4hep::deg ) ;
+
+     
+      ftdDE.addExtension< GearHandle >( new GearHandle( gearFTD, "FTDParameters" ) ) ;
+     //============================================================================================
+
+
+
       // --- LCDD::apply() expects return code 1 if all went well ! ----
       return 1;
     }