The ray-tracing package Tachyon
is distributed with Sage.
The 3D plots look very nice but tend to take a bit more setting up.
Here is an example of a parametric space curve:
sage: f = lambda t: (t,t^2,t^3) sage: t = Tachyon(camera_center=(5,0,4)) sage: t.texture('t') sage: t.light((-20,-20,40), 0.2, (1,1,1)) sage: t.parametric_plot(f,-5,5,'t',min_depth=6)
Type t.show()
to view this.
Other examples are in the Sage Reference Manual.
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