// blobify.inc
//
// Ryan Budge
// budgery@yahoo.com
//
// April 27,2004



/* Blobify usage :
      
      Blobify ( obj, vec1, vec2, res, elrad, thresh )
      
      obj    - object to blobify
      vec1   - one corner of scan box (obj should be contained within scan box)
      vec2   - far corner of scan box (order of vec1 and vec2 interchangable)
      res    - scan resolution (higher=better, slower; lower=uglier, faster; upper limit 256?)
      elrad  - radius of blob elements
      thresh - blob threshold (higher=smoother; if set too high, blob will disappear)

   Inner details :
   
      Step 1 : Scan object, store all points inside obj into arrA
      Step 2 : For each point in arrA, eliminate points surrounded by other points,
               effectively leaving only the surface of obj, store those points in arrB
      Step 3 : Input arrB points into blob

*/


#macro Blobify ( obj, vec1, vec2, res, elrad, thresh )
   
   //Step 1
   #local i=0;
   #local j=0;
   #local k=0;
   
   #local arrA = array[res][res][res];
   #local arrA[0][0][0]=0;
   
   #while (i<res)
      #local j=0;
      #while (j<res)
         #local k=0;
         #while (k<res)
            #local rel_coord=(<i,j,k>/(res-1))*(vec2-vec1)+vec1;
            #local arrA[i][j][k]=inside(obj, rel_coord);
            #local k=k+1;
         #end
         #local j=j+1;
      #end
      #local i=i+1;
   #end
   //End Step 1
   
   //Step 2
   #local i=0;
   #local j=0;
   #local k=0;
   #local edge_points=0;
   #local arrB = array[pow(res,3)];
   #local arrB[0]=<0,0,0>;
   #local edge=1;
   
   #while (i<res)
      #local j=0;
      #while (j<res)
         #local k=0;
         #while (k<res)
            #if (arrA[i][j][k])
               #local scanx=0;
               #while (scanx<3)
                  #local scany=0;
                  #while (scany<3)
                     #local scanz=0;
                     #while (scanz<3)
                        #local rel_coord=<i,j,k>+<scanx,scany,scanz>-1;
                        #if (scanx=1 * scany=1 * scanz=1)
                           //nothing
                        #else
                           #if ( (i=0)+(j=0)+(k=0)+(i=res-1)+(j=res-1)+(k=res-1) )
                              #local edge=0;
                              #local scanx=2;
                              #local scany=2;
                              #local scanz=2;
                           #else
                              #local edge=edge*arrA[rel_coord.x][rel_coord.y][rel_coord.z];
                           #end
                        #end
                        #local scanz=scanz+1;
                     #end
                     #local scany=scany+1;
                  #end
                  #local scanx=scanx+1;
               #end
               #if (edge=0)
                  #local arrB[edge_points]=<i,j,k>;
                  #local edge_points=edge_points+1;
               #end
               #local edge=1;
            #end
            #local k=k+1;
         #end
         #local j=j+1;
      #end
      #local i=i+1;
   #end
   //End Step 2
   
   //Step 3
   blob {
      threshold thresh
      #local i=0;
      #while (i<edge_points)
         sphere { (arrB[i]/(res-1))*(vec2-vec1)+vec1, elrad/(res-1)*(vec2-vec1), 1 }
         #local i=i+1;
      #end
   }
   //End Step 3
   
   #undef arrA
   #undef arrB            

#end