One problem with the colorbar is that the png file
> "im.write_png (filename)" creates is upside down,
> image_demo.py creates an upside down png too.
> I see that the GTK/GDK backend does not use im.write_png()
> but uses im.as_str() which has a 'flipud' argument to flip
> the image. Is it possible for im.write_png() to take the
> 'flipud' argument and flip the image for the SVG backend?
I started working on this, but then realized I would also need to add
it to buffer_argb32, buffer_rgba and so on, and that is was much
cleaner to simply add an im.flipud() method than implement it in all
the conversion and write methods.
I just committed changes with these fixes and updated backend_ps and
backend_svg to use them. images in svg appear to be working fine now,
and the origin = 'lower'|'upper' is respected.
> The name im.as_str() is a bit vague - what kind of string?
> Something like im.as_rgba_str() would make it a bit