Added SRTTransform3D test, corrected fromMatrix bug

pyqtgraph/SRTTransform3D.py

@@ -123,6 +123,7 @@ class SRTTransform3D(Transform3D):
         m = self.matrix().reshape(4,4)
         ## translation is 4th column
         self._state['pos'] = m[:3,3]
+        
         ## scale is vector-length of first three columns
         scale = (m[:3,:3]**2).sum(axis=0)**0.5
         ## see whether there is an inversion
@@ -132,7 +133,7 @@ class SRTTransform3D(Transform3D):
         self._state['scale'] = scale
         
         ## rotation axis is the eigenvector with eigenvalue=1
-        r = m[:3, :3] / scale[:, np.newaxis]
+        r = m[:3, :3] / scale[np.newaxis, :]
         try:
             evals, evecs = numpy.linalg.eig(r)
         except:

pyqtgraph/tests/test_srttransform3d.py

@@ -0,0 +1,39 @@
+import pyqtgraph as pg
+from pyqtgraph.Qt import QtCore, QtGui
+import numpy as np
+from numpy.testing import assert_array_almost_equal, assert_almost_equal
+
+testPoints = np.array([
+                       [0, 0, 0],
+                       [1, 0, 0],
+                       [0, 1, 0],
+                       [0, 0, 1],
+                       [-1, -1, 0],
+                       [0, -1, -1]])
+
+
+def testMatrix():
+    """
+    SRTTransform3D => Transform3D => SRTTransform3D
+    """
+    tr = pg.SRTTransform3D()
+    tr.setRotate(45, (0, 0, 1))
+    tr.setScale(0.2, 0.4, 1)
+    tr.setTranslate(10, 20, 40)
+    assert tr.getRotation() == (45, QtGui.QVector3D(0, 0, 1))
+    assert tr.getScale() == QtGui.QVector3D(0.2, 0.4, 1)
+    assert tr.getTranslation() == QtGui.QVector3D(10, 20, 40)
+
+    tr2 = pg.Transform3D(tr)
+    assert np.all(tr.matrix() == tr2.matrix())
+    
+    # This is the most important test:
+    # The transition from Transform3D to SRTTransform3D is a tricky one.
+    tr3 = pg.SRTTransform3D(tr2)
+    assert_array_almost_equal(tr.matrix(), tr3.matrix())
+    assert_almost_equal(tr3.getRotation()[0], tr.getRotation()[0])
+    assert_array_almost_equal(tr3.getRotation()[1], tr.getRotation()[1])
+    assert_array_almost_equal(tr3.getScale(), tr.getScale())
+    assert_array_almost_equal(tr3.getTranslation(), tr.getTranslation())
+
+