/* Creation of Bezier patches for testing purposes. */
/* Last edited on 2009-08-21 15:30:22 by stolfilocal */

#ifndef dg_makegrid_H
#define dg_makegrid_H

#include "mdg_grid.h"
#include "dg_tree.h"
#include "bz_patch.h"

typedef bool_t mdg_cell_predicate_t
  ( mdg_cell_index_t k, 
    mdg_rank_t r, 
    bz_patch_t *b, 
    dg_tree_node_t *p
  );
  /* A client-defined predicate that is used in recursive traversals
    of the dyadic cell tree. The arguments are the index {k} of a cell
    {C}, the corresponding rank {r}, the cell's shape {b}, and a node
    of some tree that encloses {C}. The node {p} and/or the shape {b}
    may be null. */
 
dg_tree_node_t *dg_make_grid
  ( mdg_dim_t d,
    mdg_cell_index_t k,
    mdg_rank_t r,
    bz_patch_t *b,
    dg_tree_node_t *p,
    mdg_cell_predicate_t *split
  );
  /* Creates a finite multigrid whose root is the dyadic cell {C} of
    level {r} with index {k}. 
    
    If {b} is not NULL, it is taken to define the shape and/or
    function values of {C}. If the node {p} is not NULL, it is taken
    to be a node, from some other tree, that encloses {C}.
    
    The procedure generates the grid by recursive subdivision of the initial cell
    {C}. It uses the predicate {split} to decide when they should have children.
    
    More precisely, the procedure calls {split} for every
    candidate subcell {C'} of {C}, including {C} itself. 
    If {split} returns FALSE, then {C'} is included in the grid as a
    leaf cell. 
    
    If {split} returns TRUE, the procedure recursively generates
    subgrids for the two halves of {C'}. The procedure then creates a
    node for {C'}, and returns it.

    Note that the {count} fields of {n}'s ancestors will need fixing
    after the split. The shape {b} may be null. */

#endif