/* file doplot2.mac */

/*  eighteen triangles  */
disp("doplot2()")$
print("eighteen colored triangles")$
doplot2() := 
  block([cc, qlist,x1,x2,y1,y2,i,val ],
     cc : [aquamarine,beige,blue,brown,cyan,gold,goldenrod,green,khaki,
            magenta,orange,pink,plum,purple,red,salmon,skyblue,turquoise,
            violet,yellow ],            
     qlist : [ xr(-3.3,3.3), yr(-3.3,3.3) ],     
  /* top row of triangles  */
     y1  : 1,
     y2 : 3,
     for i:0 thru 5 do ( 
       x1 : -3 + i,
       x2 : x1 + 1,
       val : poly( [ [x1,y1],[x2,y1],[x1,y2]], fill( cc[i+1] ) ),
       qlist : append(qlist, [val ] ) 
     ),
  /* middle row of triangles  */
     y1 : -1,
     y2 : 1,
     for i:0 thru 5 do (
        x1 : -3 + i,
        x2 : x1 + 1,
        val : poly( [ [x1,y1],[x1,y2],[x2,y2]], fill( cc[i+7] ) ),
        qlist : append(qlist, [val ] ) 
     ),
      /* bottom row of triangles  */
     y1 : -3,
     y2 : -1,
     for i:0 thru 5 do (
       x1 : -3 + i,
       x2 : x1 + 1,
       val : poly( [ [x1,y1],[x2,y1],[x1,y2]], fill( cc[i+13] ) ),
       qlist : append(qlist, [val ] )        
     ),          
     qlist : append(qlist,[ cut(all) ] ),                    
     apply( 'qdraw, qlist )                                   
  )$