Re: [Fwd: Re: Introducing real 3d in Gnuplot (Was: Re: please try POV-Ray and VRML terminals )]

[<dan...@ie...>]

> At the moment, the design of gnuplot assumes 2D output, and therefore
all the information passed to the terminals is just 2D, *even for 3D
plots*. So we are not really after a "more feature-full 3D", just a
sensible way of making the existing 3D information available to a
terminal (such as POV-Ray) that would have something useful to do with
it.

I'm assuming the POV-Ray driver needs 3D so that it can determine
directions of shading and lighting, "ray trace" if you will?  Is that
correct?  Or does POV-Ray also allow changing of viewing angle too?

Anyway, there is still (always?) work that could be done to clean up 3D
mode in gnuplot, i.e., to better organize the similar plot elements (colo=
r
boxes, keys, margins) and code progression between 2D and 3D.  If someone
wants to take on that project, that's fine with me.  But before doing
that, let me take out some of the #ifdef'd code for reading data into 2D
and 3D plots from a file... but I have little time to do that now.  (The
new method--now similar in 2D and 3D--has been in use by default for
probably 8+ months now, so I assume it is working fine.)

As far as the 3D POV-Ray, there is a routine something like "project3d"
(?) that maps points from 3D space to the 2D view.  Perhaps that could be
made to leave points as 3D or map to 2D based upon the ability of the
terminal to accept 3D data.  We're talking a major conceptual shift,
however.  Shaking the tree a bit too much probably, and difficult to work
in without coordinated effort when many developers are working on a
project.

Dan