Re: [Matplotlib-users] Is it possible to have different color for inner and outer face of a 3D plot?

[Benjamin R. <ben...@ou...>]

On Wed, Sep 19, 2012 at 9:14 AM, Fabien Lafont <laf...@gm...>wrote:

> Actually I want to try to plot something like this picture:
>
> http://physics.aps.org/assets/d88621a594e78eea
>
> With a color for inside and another for outside.
>
>
Probably not to the level of control one may wish to have, but one can
achieve shading effects assuming a light source.  plot_surface() can assume
a light source for you, or you could provide one IIRC.  This isn't very
well documented (in fact, it is downright non-existent!).

The most simple way of getting something like what you want is to set
shade=True and not use a colormap.  This shades the surface according to
the normal vector to the surface.

One can also provide a "lightsource".  I just noticed this is not
documented.  One can specify a "lightsource" kwarg to plot_surface (note
that shade must be set to True, a cmap must be provided, and oddly enough,
facecolors has to be not None (this might be a bug)), and a colorbar won't
work (seem to throw an exception...).  By default (i.e., lightsource=None),
a matplotlib.color.LightSource object with azdeg=135 and altdeg=55 is used
to shade based on the data and colormap.  You can provide your own light
source to achieve the effect you would like by positioning it properly
(don't ask me how, I never played with that part).

I know this was kind of vague, but I hope it is at least somewhat
illuminating.

Cheers!
Ben Root