Sample demonstrating simple shadow casting from directional light source V3d_DirectionalLight.
pload MODELING VISUALIZATION
# create simple scene
box b 1 2 3
box bb -5 -5 0 10 10 0 -preview
vgldebug 1
vclear
vinit View1
vcamera -persp
vdisplay -dispMode 1 b bb
vaspects bb -material STONE
vfit
# setup light sources
set aPrsSize 75
vlight -clear
vlight -add AMBIENT -color WHITE -display amb -prsSize $aPrsSize
# add WHITE directional light source
vlight -add DIRECTIONAL -color WHITE -direction 1.0 1.0 -1.0 -head 0 -display dir1 -prsSize $aPrsSize
vlight -change 1 -castShadows 1
# add RED directional light source in disabled state
vlight -add DIRECTIONAL -color RED -direction 1.0 -1.0 -0.5 -head 0 -display dir2 -prsSize $aPrsSize
vselect 300 85
vlight -change 2 -castShadows 1
#vrenderparams -shadingModel phong
vrenderparams -shadowMapBias 0.01