I am working on some timple functions to make my own grass (I want the
challenge of making my own, I know there are some out there already).  The
way I'm doing it right now gives me the results I want (it looks like I
want it to look), but the parsing process is very slow due to the nested
loops that I use.  I am using splines to calculate the path I want.  With
my spline, I simply draw triangles to make up the grass.  There is a loops
the goes up the spline, while drawing triangles.  This loop is contained in
another loop whose roll it is to create multiple blades.  Heck, here is the
source code:

#declare counter=0;
#declare num_blades=12000;

#declare s_point1=<0,0,0>;
#declare s_point2=<0,0,0>;
#declare s_step=.1;
#declare blade_width = .025;



#while( counter < num_blades)

#declare num1=((rand(R2)-.5)*30) ;//-11 ;

#declare num2=0;

#declare num3=(rand(R2)-.5)*30;//- 11  ;

#declare rot = rand(R2)*360;

#declare ctr = 0;


#declare sway=cosd(clock)*.025;

#declare s = spline {quadratic_spline  0, <0,0,0> .5, <0, .5,0> 1, <0,1,.5>
}



#while (ctr < 1)
  /*sphere {
    <s(ctr).x,s(ctr).y,s(ctr).z>,.02
    pigment { rgb <1-ctr,ctr,0> }     */



    #declare s_point1=s(ctr);
    #declare s_point2=s(ctr+s_step);


    triangle {<s_point1.x-blade_width,s_point1.y,s_point1.z>
<s_point1.x+blade_width,s_point1.y,s_point1.z>
<s_point1.x-blade_width,s_point2.y,s_point2.z> pigment {color rgb <0,ctr,0>
} finish {diffuse .5} translate <num1,0,num3>   rotate y*rot}
    triangle {<s_point1.x+blade_width,s_point1.y,s_point1.z>
<s_point1.x+blade_width,s_point2.y,s_point2.z>
<s_point1.x-blade_width,s_point2.y,s_point2.z> pigment {color rgb <0,ctr,0>
} finish {diffuse .5} translate <num1,0,num3>  rotate y*rot}


  //}




  #declare ctr = ctr + s_step;
#end


#declare counter = counter + 1;
#end







As already stated, the parsing step is very slow and takes a lot of ram
(once it hits swap, the time required goes through the roof.  Can someone
help me come up with a good optimization scheme?

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