how can I draw pie charts in PsychoPy Builder

I want to create half a pie chart to use in an existing builder script and I'm not sure how to go about it. (its actually to implement a speedometer)

Does anyone have any suggestions?

I realise I'll need to dip into some python code.

This old posting in Google Groups https://groups.google.com/forum/#!topic/psychopy-users/JcnS7ZtuVlM gives some sample code utilising pylab but they couldn't get it to work when it was dropped into Builder.

Thanks,

Solution

I've worked out how to do this now so here's my method for the record.

# create 1st sector - use the **ori** parameter to control what bearing it 
# starts on (0 is vertical)
rad1 = visual.RadialStim( win=win, name='rad1', color=[1,-1,-1],
    angularCycles = 0, radialCycles = 0, radialPhase = 0.5, colorSpace = 'rgb', 
    ori= -90.0, pos=(0.5, -0.3), size=(0.3,0.3),  visibleWedge=(0.0, 135.0) )
rad1.draw()

#now draw another sector next to it by using **ori** again to line them up
rad2 = visual.RadialStim( win=win, name='rad1', color=[-1,1,-1],
    angularCycles = 0, radialCycles = 0, radialPhase = 0.5, colorSpace = 'rgb', 
    ori= 45.0, pos=(0.5, -0.3), size=(0.3,0.3),  visibleWedge=(0.0, 45.0) )
rad2.draw()

This works fine in Builder, dropping it into a code segment and knowing that Builder uses a window called win

Note that this uses the default mode for size (-1 to 1) so it will look different on different screen sizes. you may want to change to cm (and calibrate your monitor) if you want it to be round.

Thanks to Jon P for his suggestion (via google groups) to use RadialStim)