Home Manual Packages Global Index Keywords Quick Reference | # functions in pl3d.i - l
light3 |
                 light3, ambient=a_level,
                         diffuse=d_level,

    		    specular=s_level,
    		    spower=n,
    		    sdir=xyz
         Sets lighting properties for 3D shading effects.
         A surface will be shaded according to its to its orientation
         relative to the viewing direction.
         The ambient level A_LEVEL is a light level (arbitrary units)
         that is added to every surface independent of its orientation.
         The diffuse level D_LEVEL is a light level which is proportional
         to cos(theta), where theta is the angle between the surface
         normal and the viewing direction, so that surfaces directly
         facing the viewer are bright, while surfaces viewed edge on are
         unlit (and surfaces facing away, if drawn, are shaded as if they
         faced the viewer).
         The specular level S_LEVEL is a light level proportional to a high
         power spower=N of 1+cos(alpha), where alpha is the angle between
         the specular reflection angle and the viewing direction.  The light
         source for the calculation of alpha lies in the direction XYZ (a
         3 element vector) in the viewer's coordinate system at infinite
         distance.  You can have ns light sources by making S_LEVEL, N, and
         XYZ (or any combination) be vectors of length ns (3-by-ns in the
         case of XYZ).  (See source code for specular_hook function
         definition if powers of 1+cos(alpha) aren't good enough for you.)
         With no arguments, return to the default lighting.
       EXAMPLES:
         light3, diffuse=.1, specular=1., sdir=[0,0,-1]
           (dramatic "tail lighting" effect)
         light3, diffuse=.5, specular=1., sdir=[1,.5,1]
           (classic "over your right shoulder" lighting)
         light3, ambient=.1,diffuse=.1,specular=1.,
                 sdir=[[0,0,-1],[1,.5,1]],spower=[4,2]
           (two light sources combining previous effects)

    interpreted function, defined at i/pl3d.i   line 262
SEE ALSO: | rot3, save3, restore3
limit3 |
                 limit3, xmin,xmax, ymin,ymax
              or limit3, xmin,xmax, ymin,ymax, zmin,zmax

         Set the 3D axis limits for use with the cage.
         Use keyword aspect=[ax,ay,az] to set the aspect ratios of the
         cage to ax:ay:az -- that is, the ratios of the lengths of the
         cage axes will become ax:ay:az.

    interpreted function, defined at i/pl3d.i   line 181
SEE ALSO: | cage3, range3, plwf, plwf, orient3