Construct the sphere with this pattern:

> restart:

> r:=sin(s):

> x:=r*cos(t):

> y:=r*sin(t):

> z:=cos(s):

> a:=plot3d([x,y,z],s=0..Pi,t=0..Pi/3,scaling=constrained,color=yellow):

> b:=plot3d([x,y,z],s=0..Pi,t=Pi/3..2*Pi/3,scaling=constrained,color=green):

> c:=plot3d([x,y,z],s=0..Pi,t=2*Pi/3..Pi,scaling=constrained,color=red):

> d:=plot3d([x,y,z],s=0..Pi,t=Pi..4*Pi/3,scaling=constrained,color=blue):

> e:=plot3d([x,y,z],s=0..Pi,t=4*Pi/3..5*Pi/3,scaling=constrained,color=brown):

> f:=plot3d([x,y,z],s=0..Pi,t=5*Pi/3..2*Pi,scaling=constrained,color=coral):

> with(plots):

Warning, the name changecoords has been redefined

> g;

> with(plottools):

> vrml(g,"c:/042/9/9-3.wrl",background_color=white);

>