DM-8889: Add detector z-offsets

doc/lsst.obs.lsst/adding-a-camera.rst

@@ -34,7 +34,9 @@ To add a new camera (e.g., ``fooCam``, made up of 9 CCDs in a single
    default to 0.0 and the yaw entry is not generated.  These offsets
    are interpreted relative to the nominal positions given in cameraHeader.yaml
    for each type of raft, as adjusted for the centre of the raft; these
-   values are therefore reasonable.
+   values are therefore reasonable.  (Note that offsets here and elsewhere may
+   either be specified as 2-tuples, in which case the z-offset is inferred to be
+   0.0, or directly as 3-tuples with their z-offset explicit).
 
    The yaw (rotation in the plane of the detector) is measured in degrees,
    anticlockwise as shown in cameraGeomUtils.plotFocalPlane (i.e. with ``R00`` in

policy/lsstCam/R00W.yaml

@@ -8,11 +8,11 @@ R00W :
 
   geometryWithinRaft :
     SW0 : {
-      offset : [2.5, 1.4375],
+      offset : [2.5, 1.4375, -1.5],  # extrafocal
       yaw : 0.0,
     }
     SW1 : {
-      offset : [2.5, 3.5625],
+      offset : [2.5, 3.5625, 1.5],  # intrafocal
       yaw : 180.0,
     }
 

policy/lsstCam/R04W.yaml

@@ -8,11 +8,11 @@ R04W :
 
   geometryWithinRaft :
     SW0 : {
-      offset : [2.5, 1.4375],
+      offset : [2.5, 1.4375, -1.5],  # extrafocal
       yaw : 0.0,
     }
     SW1 : {
-      offset : [2.5, 3.5625],
+      offset : [2.5, 3.5625, 1.5],  # intrafocal
       yaw : 180.0,
     }
 

policy/lsstCam/R40W.yaml

@@ -8,11 +8,11 @@ R40W :
 
   geometryWithinRaft :
     SW0 : {
-      offset : [2.5, 1.4375],
+      offset : [2.5, 1.4375, -1.5],  # extrafocal
       yaw : 0.0,
     }
     SW1 : {
-      offset : [2.5, 3.5625],
+      offset : [2.5, 3.5625, 1.5],  # intrafocal
       yaw : 180.0,
     }
 

policy/lsstCam/R44W.yaml

@@ -8,11 +8,11 @@ R44W :
 
   geometryWithinRaft :
     SW0 : {
-      offset : [2.5, 1.4375],
+      offset : [2.5, 1.4375, -1.5],  # extrafocal
       yaw : 0.0,
     }
     SW1 : {
-      offset : [2.5, 3.5625],
+      offset : [2.5, 3.5625, 1.5],  # intrafocal
       yaw : 180.0,
     }
 

python/lsst/obs/lsst/script/generateCamera.py

@@ -85,22 +85,23 @@ def applyRaftYaw(offset, raftYaw):
     Parameters
     ----------
     offset : `list` of `float`
-        A list of the offsets to rotate: [x, y]
+        A list of the offsets to rotate: [x, y, z]
     raftYaw : `float`
         Raft yaw angle in degrees.
 
     Returns
     -------
     offsets : `list` of `float
-        2-item sequence of floats containing the rotated offsets.
+        3-item sequence of floats containing the rotated offsets.
     """
     if raftYaw == 0.:
         return offset
-    new_offset = np.zeros(2, dtype=np.float)
+    new_offset = np.zeros(3, dtype=np.float)
     sinTheta = np.sin(np.radians(raftYaw))
     cosTheta = np.cos(np.radians(raftYaw))
     new_offset[0] = cosTheta*offset[0] - sinTheta*offset[1]
     new_offset[1] = sinTheta*offset[0] + cosTheta*offset[1]
+    new_offset[2] = offset[2]
     return new_offset
 
 
@@ -232,6 +233,8 @@ def indent():
             nindent += 1
 
             raftOffset = perRaftData["offset"]
+            if len(raftOffset) == 2:
+                raftOffset.append(0.0)  # Default offset_z is 0.0
             id0 = perRaftData['id0']
             try:
                 raftYaw = perRaftData['yaw']
@@ -242,9 +245,11 @@ def indent():
             for ccdName, ccdLayout in ccds.items():
                 if ccdName in geometryWithinRaft:
                     doffset = geometryWithinRaft[ccdName]['offset']
+                    if len(doffset) == 2:
+                        doffset.append(0.0)  # Default offset_z is 0.0
                     yaw = geometryWithinRaft[ccdName]['yaw'] + raftYaw
                 else:
-                    doffset = (0.0, 0.0,)
+                    doffset = (0.0, 0.0, 0.0)
                     yaw = None
 
                 print(indent(), "%s_%s : " % (raftNameMap.get(raftName, raftName), ccdName), file=fd)
@@ -256,10 +261,13 @@ def indent():
                 print(indent(), "serial : %s" % (raftCcdData['ccdSerials'][ccdName]), file=fd)
                 print(indent(), "physicalType : %s" % (detectorType), file=fd)
                 print(indent(), "refpos : %s" % (ccdLayout['refpos']), file=fd)
+                if len(ccdLayout['offset']) == 2:
+                    ccdLayout['offset'].append(0.0)  # Default offset_z is 0.0
                 ccdLayoutOffset = applyRaftYaw([el1+el2 for el1, el2 in zip(ccdLayout['offset'], doffset)],
                                                raftYaw)
-                print(indent(), "offset : [%g, %g]" % (ccdLayoutOffset[0] + raftOffset[0],
-                                                       ccdLayoutOffset[1] + raftOffset[1]),
+                print(indent(), "offset : [%g, %g, %g]" % (ccdLayoutOffset[0] + raftOffset[0],
+                                                           ccdLayoutOffset[1] + raftOffset[1],
+                                                           ccdLayoutOffset[2] + raftOffset[2]),
                       file=fd)
                 if yaw is not None:
                     print(indent(), "yaw : %g" % (yaw), file=fd)

tests/test_generateCamera.py

@@ -97,6 +97,8 @@ def testGenerateCamera(self):
         self.assertEqual([x for x in content['CCDs'] if 'W_' in x], [])
         self.assertEqual(content["name"], "LSSTCam")
         self.assertEqual(content["plateScale"], 20.0)
+        # SW0 is extrafocal is negative-z in DVCS
+        self.assertEqual(content["CCDs"]["R04_SW0"]["offset"][2], -1.5)
 
     def testFailures(self):
         with self.assertRaises(RuntimeError):