grabWindowPixmap() broken for QCDATWidget

[remram44]

The saveToPNG() implementation in QCDATWidget doesn't correctly handle the case where the filename argument is None, which makes VCS fail.

Traceback (most recent call last):
  File "/home/remram/Documents/programming/uvcdat-vistrails/vistrails/packages/spreadsheet/spreadsheet_tabcontroller.py", line 426, in exportSheetToSingleImageActionTriggered
    self.currentWidget().exportSheetToImage(filename)
  File "/home/remram/Documents/programming/uvcdat-vistrails/vistrails/packages/spreadsheet/spreadsheet_tab.py", line 543, in exportSheetToImage
    pix = widget.grabWindowPixmap()
  File "/home/remram/Documents/programming/uvcdat-vistrails/vistrails/packages/uvcdat_cdms/vtk_classes.py", line 836, in grabWindowPixmap
    uchar = self.saveToPNG(None)  # crashes
  File "/home/remram/Documents/programming/uvcdat-vistrails/vistrails/packages/uvcdat_cdms/init.py", line 1511, in saveToPNG
    self.canvas.png(filename)
  File "/home/remram/uvcdat-builds/builds/32f3893f053107374d2b4b8fb0feee5efbcaedee/install/lib/python2.7/site-packages/vcs/Canvas.py", line 4783, in png
    return self.backend.png(file,width,height,units,draw_white_background, **args )
  File "/home/remram/uvcdat-builds/builds/32f3893f053107374d2b4b8fb0feee5efbcaedee/install/lib/python2.7/site-packages/vcs/VTKPlots.py", line 1577, in png
    if not file.split('.')[-1].lower() in ['png']:
AttributeError: 'NoneType' object has no attribute 'split'

I'm not sure what is expected here.

[remram44]

Options are: make VisTrails feed a temporary filename to VCS, or directly get an in-memory buffer from VCS.

[remram44]

Traceback as of 2.2.0-45, vistrails 2.2.0-12

Traceback (most recent call last):
  File "/home/remram/Documents/programming/uvcdat-vistrails/vistrails/packages/spreadsheet/spreadsheet_tabcontroller.py", line 426, in exportSheetToSingleImageActionTriggered
    self.currentWidget().exportSheetToImage(filename)
  File "/home/remram/Documents/programming/uvcdat-vistrails/vistrails/packages/spreadsheet/spreadsheet_tab.py", line 543, in exportSheetToImage
    pix = widget.grabWindowPixmap()
  File "/home/remram/Documents/programming/uvcdat-vistrails/vistrails/packages/uvcdat_cdms/vtk_classes.py", line 836, in grabWindowPixmap
    uchar = self.saveToPNG(None)
  File "/home/remram/Documents/programming/uvcdat-vistrails/vistrails/packages/uvcdat_cdms/init.py", line 1511, in saveToPNG
    self.canvas.png(filename)
  File "/home/remram/uvcdat-builds/builds/9f25d777ca82a9bd383f232c26b579e4912c88e8/install/lib/python2.7/site-packages/vcs/Canvas.py", line 4787, in png
    return self.backend.png(file,width,height,units,draw_white_background, **args )
  File "/home/remram/uvcdat-builds/builds/9f25d777ca82a9bd383f232c26b579e4912c88e8/install/lib/python2.7/site-packages/vcs/VTKPlots.py", line 857, in png
    if not file.split('.')[-1].lower() in ['png']:
AttributeError: 'NoneType' object has no attribute 'split'

Second attempt at exporting causes segmentation fault:

QPaintDevice: Cannot destroy paint device that is being painted

[remram44]

@doutriaux1 Is rendering to a memory buffer going to be supported in vcs? It looks like VCS plots have never been exportable in the spreadsheet since their introduction in 2011.

[rexissimus]

This seems to work:

diff --git a/Packages/vcs/Lib/VTKPlots.py b/Packages/vcs/Lib/VTKPlots.py
index 1c1f112..bd894b0 100644
--- a/Packages/vcs/Lib/VTKPlots.py
+++ b/Packages/vcs/Lib/VTKPlots.py
@@ -851,17 +851,18 @@ def gif(self,filename='noname.gif', merge='r', orientation=None, geometry='1600x

   def png(self, file, width=None,height=None,units=None,draw_white_background = True, **args ):

+@ -854,13 +1583,14 @@ def png(self, file, width=None,height=None,units=None,draw_white_background = Tr
         if self.renWin is None:
           raise Exception,"Nothing to dump aborting"

-        if not file.split('.')[-1].lower() in ['png']:
-            file+='.png'
-
-        try:
-          os.remove(file)
-        except:
-          pass
+        if file is not None:
+            if not file.split('.')[-1].lower() in ['png']:
+                file+='.png'

+            try:
+              os.remove(file)
+            except:
+              pass

         #if width is not None and height is not None:
         #  self.renWin.SetSize(width,height)
@@ -883,8 +884,16 @@ def png(self, file, width=None,height=None,units=None,draw_white_background = Tr

         writer = vtk.vtkPNGWriter()
         writer.SetInputConnection(imgfiltr.GetOutputPort())
-        writer.SetFileName(file)
+
+        if file is not None:
+            writer.SetFileName(file)
+        else:
+            writer.WriteToMemoryOn()
         writer.Write()
+        if file is not None:
+            return file
+        else:
+            return writer.GetResult()

[doutriaux1]

@remram44 I believe that's what bg=1 is for.

[remram44]

Is it something cdat used to have?

[doutriaux1]

still does x.plot(data,bg=1)