Re: [Matplotlib-users] matplotlib 3D: equivalent to Matlab patch()?

On Thu, Sep 29, 2011 at 4:31 PM, Holger Brandsmeier <
hol...@sa...> wrote:

> Hi Ben,
>
> in your example
> > http://matplotlib.sourceforge.net/examples/mplot3d/polys3d_demo.html
> the essential line is:
>  ax.add_collection3d(poly, zs=zs, zdir='y')
> according to everything I see this can only draw something that is
> made out of several axes parallel parts. I don't think how with such a
> command you could end up with some picture like:
>
> http://matplotlib.sourceforge.net/plot_directive/mpl_examples/mplot3d/surface3d_demo.hires.png


That is correct.  It is only for simple conversions.


>
> What I want to plot should look like that picture (with is part of
> your gallery), just that I don't have a meshgrid data underlying.
>
>
That is why you have to work with the 3D objects from
mpl_toolkits.mplot3d.art3d directly.  There isn't a lot of documentation, so
your best bet is to look at the source code of the module.


> Your second example seems to have the same limitation
>  http://matplotlib.sourceforge.net/examples/mplot3d/pathpatch3d_demo.html
> just it works with the command
>  art3d.pathpatch_2d_to_3d(p, z=0, zdir="x")
>
> The only way that I currently see is that I call
>  ax.plot_surface()
> for each quadrilateral of my mesh.
>
>
That would be overkill.  However, try checking out the source code for
plot_surface() to see how it creates its Poly3DCollection object.

Ben Root