[Plplot-devel] 3D plots enhancements commited to HEAD.

[<jc...@fe...>]

Hi,

I have just now committed some enhancements to 3d plots, including=20
changes to x08c.c to show the new features.

In plot3d() the "opt" argument now accepts another option, MAG_COLOR,=20
that colors the grid with a color dependent of the function magnitude.

In plotfc3d() the "side" argument is now called "opt", that accepts
 *  SURF_CONT -- draw contour at surface
 *  SURF_BASE -- draw contour at bottom xy plane
 *  DRAW_SIDE -- draw sides (this one is currently disabled, as is ugly)
 there are also two new arguments, clevel and nlevel, to specify the=20
levels of the contours.
The surface contour lines are not very good, as they are merely straight=20
lines drawn on the intersection of the contour plane with each triangle=20
that makes up the surface. The contour lines drawn at the xy plane are=20
derived from the ones drawn from plcont(), and are quite good.

x08c, besides showing the new features, has also a new function, the log=20
of the Rosenbrock function (know by optimization people). It can be=20
invoked with the command line option "-rosen". It is nicer than the=20
sombrero like default function plotted by x08c, and has the nice=20
feature of not being symmetric.

I have also changed plconf() and associated functions, and added a new=20
function cont_store(),  in order to enable  plconf()  to plot the=20
contour lines to memory. You can see an example of its usage in=20
plotfc3d().

Finally I would like to merge two API entries, but have not done it=20
until we discuss the matter.
The API in question are plotfc3d() and plotsh3d(). As they are almost=20
identical, only the way of coloring the surface is different, I think=20
that is makes sense to merge both.
plotfc3d() is so recent that nobody else other than us has ever seen it,=20
so any change will make no harm to users. plotsh3d() is older, but as=20
it was buggy I don't think that changing it will make any difference to=20
users.
So, what I propose is just to remove both API entries and create a new=20
one, plsurf3d() that will have the capabilities of the old functions=20
managed with the "opt" argument: if LIGHT_SHADE, than plotsh3d() will=20
be handled, else if MAG_SHADE (or LIGHT_SHADE not defined) plotfc3d()=20
will be handled.
What do you think of this?

Joao