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RE: SpericalPlot3D in Gray?

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  • Subject: [mg72120] RE: [mg72073] SpericalPlot3D in Gray?
  • From: "David Park" <djmp at earthlink.net>
  • Date: Wed, 13 Dec 2006 06:38:54 -0500 (EST)

Thomas,

You could do it the following way...

SphericalPlot3D[ {(theta/2 - Pi/2)^2, {SurfaceColor[GrayLevel[0.7]],
        EdgeForm[GrayLevel[0.5]]}}, {theta, 0, Pi}, {phi, 0, 2Pi},
    PlotPoints -> {54, 34},
    LightSources -> {{{1.`, 0.`, 1.`}, GrayLevel[0.5]}, {{1.`, 1.`, 1.`},
          GrayLevel[0.5]}, {{0.`, 1.`, 1.`}, GrayLevel[0.5]}},
    Axes -> False,
    BoxStyle -> Gray,
    ImageSize -> 350];

Instead of a simple radial function you use a list where the first item is
the radial function and the second item is color directives for the surface.
The color directives could be functions of phi and theta. But to show the
surface color properly you have to use neutral colors for the light sources.

Another way to do this is with the DrawGraphics package from my web site
below. Here, if the surface color is uniform, it can be placed before the
SphericalDraw3D statement. NeutralLighting[saturation, brightness, ambient]
is an easier DrawGraphics command that allows you to control the light
sources. (It also allows the lights to be rotated about the z axis.) In both
of the plots I also used EdgeForm so that the 'mesh' lines were only a
slightly darker shade of the surface color. Subdued edges generally look
better than black edges.

Needs["DrawGraphics`DrawingMaster`"]

Draw3DItems[
    {SurfaceColor[GrayLevel[0.7]], EdgeForm[GrayLevel[0.5]],
      SphericalDraw3D[ (theta/2 - Pi/2)^2, {theta, 0, Pi}, {phi, 0, 2Pi},
        PlotPoints -> {54, 34}]},
    NeutralLighting[0.0, 0.5, 0.1],
    BoxStyle -> Gray,
    ImageSize -> 300];

David Park
djmp at earthlink.net
http://home.earthlink.net/~djmp/

From: Thomas Rausch [mailto:thomas.rausch at lehrer.uni-karlsruhe.de]

Hi,

is there a Possibility to show figures with SpericalPlot3D in
gray-shades?

Thanks



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