Ghosted Axis Text

[capaulson]

I've had issues with axis 'ghosting' when saving PNG images. The code to generate plots follows:

    plot = mlab.contour3d(scalars, contours=10, opacity=.8, transparent=True, figure=predictFig)
    plot.compute_normals = False
    a = mlab.axes(xlabel='Area', ylabel='Aspect Ratio', zlabel='Sweep', ranges=ranges1, nb_labels=2)
    a.axes.corner_offset=0.0601
    a.title_text_property.font_family = 'times'
    a.label_text_property.font_family = 'times'
    engine = mlab.get_engine()
    scene = engine.current_scene
    scene.scene.isometric_view()
    f = mlab.gcf()
    f.scene.camera.zoom(.9)
    f.scene.render()
    mlab.savefig('%s_prediction.pdf' % name, figure=predictFig)

This sometimes works:

And sometimes produces ghosted text:

Any ideas about what's going on?

[capaulson]

bump. any ideas on how to fix this?

[kitchoi]

This is caused by the orientation of the object being close to where if you rotate the object a bit, the axis will swap side. The ghost axes occur when saving a figure, i.e. when everything is rendered again. To prevent this from happening, you may (1) set the view of the camera so that the axis is safely on one side despite small deviation; OR (2) set a.axes.fly_mode = "none" then the axes would be fixed

[kitchoi]

For (1), setting the camera view can be achieved like this:

mlab.view(50.5, 60.5, 210.8, [33.6, 35., 28.5])

One can run with interactive python session or in mayavi2 and play with the scene to find the optimal orientation, then call mlab.view() to get the view setting.

@capaulson Hope this help.