Make viewer more robust

occmodel/occmodel.pyx

@@ -37,9 +37,16 @@ cdef class Tesselation:
         args = self.nvertices(), self.nranges()
         return "(nvertices = %d, ranges = %d)" % args
 
+    cpdef bint isValid(self):
+        cdef c_OCCTesselation *occ = <c_OCCTesselation *>self.thisptr
+        return occ.vertices.size() > 0 and occ.ranges.size() > 0
+
     cdef setArrays(self):
         cdef c_OCCTesselation *occ = <c_OCCTesselation *>self.thisptr
 
+        if not self.isValid():
+            return
+
         self.verticesItemSize = sizeof(float)
         self.rangesItemSize = sizeof(unsigned int)
 
@@ -106,9 +113,17 @@ cdef class Mesh:
         args = self.nvertices(), self.ntriangles(), self.nnormals()
         return "(nvertices = %d, ntriangles = %d, nnormals = %d)" % args
 
+    cpdef bint isValid(self):
+        cdef c_OCCMesh *occ = <c_OCCMesh *>self.thisptr
+        return occ.vertices.size() > 0 and occ.normals.size() > 0 and \
+               occ.triangles.size() > 0
+
     cdef setArrays(self):
         cdef c_OCCMesh *occ = <c_OCCMesh *>self.thisptr
 
+        if not self.isValid():
+            return
+
         self.verticesItemSize = sizeof(float)
         self.normalsItemSize = sizeof(float)
         self.trianglesItemSize = sizeof(unsigned int)

occmodel/occmodelviewer.py

@@ -1,4 +1,5 @@
 # -*- coding: utf-8 -*-
+from __future__ import print_function
 import sys
 import math
 import array
@@ -145,7 +146,9 @@ def addObject(self, obj, color = None):
             res.color = color
 
             tess = obj.tesselate()
-
+            if not tess.isValid():
+                return False
+
             # update bounding box
             bbox = obj.boundingBox()
             self.bbox.addPoint(bbox.min)
@@ -170,7 +173,9 @@ def addObject(self, obj, color = None):
             res = FaceObj()
 
             mesh = obj.createMesh()
-
+            if not mesh.isValid():
+                return False
+
             # update bounding box
             bbox = obj.boundingBox()
             self.bbox.addPoint(bbox.min)
@@ -227,7 +232,9 @@ def addObject(self, obj, color = None):
             res = SolidObj()
 
             mesh = obj.createMesh()
-
+            if not mesh.isValid():
+                return False
+
             # update bounding box
             bbox = obj.boundingBox()
             self.bbox.addPoint(bbox.min)
@@ -272,6 +279,11 @@ def addObject(self, obj, color = None):
             )
 
             self.objects.add(res)
+
+        else:
+            raise GLError('unknown object type')
+
+        return True
 
     def onSetup(self):
         self.ui = gl.UI()
@@ -651,7 +663,7 @@ def onIsoView(self):
         self.onZoomExtents()
 
 
-def viewer(objs, colors = None):
+def viewer(objs, colors = None, logger = sys.stderr):
     if not isinstance(objs, (tuple,list)):
        objs = (objs,)
 
@@ -668,10 +680,11 @@ def viewer(objs, colors = None):
     for obj, color in itertools.izip(objs, itertools.cycle(colors)):
         # skip Null objects.
         if obj.isNull():
-            print("skipped object: '%s'" % str(obj))
+            print("skipped Null object", file=logger)
             continue
 
-        mw.addObject(obj, color)
+        if not mw.addObject(obj, color):
+            print("skipped object", file=logger)
 
     mw.onIsoView()
     mw.mainLoop()