Changeset 1383

Timestamp:

Jun 13, 2014 5:40:58 PM (9 years ago)

Author:

toby

Message:

fix bug where 'zero' rotations flips structure plot

File:

• trunk/GSASIIplot.py (modified) (5 diffs)

trunk/GSASIIplot.py

@@ -3227 +3227 @@
         return Bonds
 
+    # PlotStructure initialization here
     ForthirdPI = 4.0*math.pi/3.0
     generalData = data['General']
@@ -3641 +3642 @@
         
     def SetRotation(newxy):
-#first get rotation vector in screen coords. & angle increment        
+        'Perform a rotation in x-y space due to a left-mouse drag'
+    #first get rotation vector in screen coords. & angle increment        
         oldxy = drawingData['oldxy']
         if not len(oldxy): oldxy = list(newxy)
@@ -3648 +3650 @@
         V = np.array([dxy[1],dxy[0],0.])
         A = 0.25*np.sqrt(dxy[0]**2+dxy[1]**2)
-# next transform vector back to xtal coordinates via inverse quaternion
-# & make new quaternion
+        if not A: return # nothing changed, nothing to do
+    # next transform vector back to xtal coordinates via inverse quaternion
+    # & make new quaternion
         Q = drawingData['Quaternion']
         V = G2mth.prodQVQ(G2mth.invQ(Q),np.inner(Bmat,V))
@@ -3655 +3658 @@
         Q = G2mth.prodQQ(Q,DQ)
         drawingData['Quaternion'] = Q
-# finally get new view vector - last row of rotation matrix
+    # finally get new view vector - last row of rotation matrix
         VD = np.inner(Bmat,G2mth.Q2Mat(Q)[2])
         VD /= np.sqrt(np.sum(VD**2))
@@ -4142 +4145 @@
         Draw('focus')
         
-    # PlotStructure execution starts here
+    # PlotStructure execution starts here (N.B. initialization above)
     try:
         plotNum = G2frame.G2plotNB.plotList.index(generalData['Name'])