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

[V. <gae...@en...>]

On Wed, Apr 13, 2005 at 09:40:10PM +0200, Hans-Bernhard Broeker wrote:
> [Gael: please subscribe yourself to the mailing list --- it's getting=20
> cumbersome to manually approve each mail you send to it.]
  Done.


  Just to answer the discussion that has been going on in the "other"
threat" (that I have ne seen until today), I think that to add openGL
interactive terminal is a great idea, and I think it would be one of the
major benefits of having a proper 3D API, but such a terminal will not
allow to do "printouts", and povray seems well suited for that. Anyhow,
writing a povray terminal is rather easy (once the term3d api is done),
where as I have no clue how to handle openGL, and I therefore do not
know how hard writing a terminal that uses openGL would be.

  I must clarify my previous posts : when I was talking of "interface",
I always meant API and not user interface.

  I was not aware of the term.c:do_arrow() and do_point(), I need to
spend more time reading gnuplot's code. Yes this is maybe a solution,
but if you look at the way do_3dplot is currently written there is a lot
of work to do to break it in routines that separate the data handling
and resizing, from the projection and the removing of the hidden lines.

  For those do not know povray well, here is a brief description of what
can be done with it.

  Povray takes a 3D description of the scene, with camera and light. An
example of a povray file would be something like=20

#include "colors.inc"
camera {location <0,2,-3> look_at <0,1,0>}
light_source {<6,6,-2> color White}
plane {<0,1,0> pigment {color Yellow}
sphere {<0,1,0> pigment {color Red} finish {phong 1}}

  As you can see povray is preprocessed by CPP which allows to define
"Vector" macros, or a camera position defined by the same angles then
Gnuplot (povray can do math). Povray is like TeX, it is not interactive,
is only processes scenes and returns bitmap images.

--
  Ga=EBl