proyector 3d frontal amb rotació

k·<(c_{1}+(-1)a_{1}),(c_{2}+(-1)a_{2}),(c_{3}+(-1)a_{3})>=...
...i·<cos(s),sin(s),0>+j·<(-1)sin(s),cos(s),0>+<0,0,1>


k=( 1/(c_{3}+(-1)a_{3}) )
i=( (c_{1}+(-1)a_{1})cos(s)+(c_{2}+(-1)a_{2})sin(s) )/(c_{3}+(-1)a_{3})
j=( (c_{2}+(-1)a_{2})cos(s)+(c_{1}+(-1)a_{1})(-1)sin(s) )/(c_{3}+(-1)a_{3})

x·<1,0,0>=...
...( (c_{1}+(-1)a_{1})( cos(s) )^{2}+(c_{2}+(-1)a_{2})sin(s)cos(s) )/(c_{3}+(-1)a_{3})+...
...( (c_{2}+(-1)a_{2})(-1)sin(s)cos(s)+(c_{1}+(-1)a_{1})( sin(s) )^{2} )/(c_{3}+(-1)a_{3})


y·<0,1,0>=...
...( (c_{1}+(-1)a_{1})sin(s)cos(s)+(c_{2}+(-1)a_{2})( sin(s) )^{2} )/(c_{3}+(-1)a_{3})+...
...( (c_{2}+(-1)a_{2})( cos(s) )^{2}+(c_{1}+(-1)a_{1}(-1)sin(s)cos(s) )/(c_{3}+(-1)a_{3})