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#include "config.h"
#include <assert.h>
#include <ccan/container_of/container_of.h>
#include <ccan/ptrint/ptrint.h>
#include <ccan/aga/aga.h>
#include "simple-graph.h"
static ptrint_t *grid_first_edge(const struct aga_graph *g,
const struct aga_node *n)
{
return int2ptr(1);
}
static ptrint_t *grid_next_edge(const struct aga_graph *g,
const struct aga_node *n,
ptrint_t *e)
{
int index = ptr2int(e);
if (index < 4)
return int2ptr(index + 1);
else
return NULL;
}
static int grid_edge_info(const struct aga_graph *g,
const struct aga_node *n,
ptrint_t *e, struct aga_edge_info *ei)
{
struct grid_graph *gg = container_of(g, struct grid_graph, sg.g);
int ni = n - gg->sg.nodes;
int x = ((ni - 1) % gg->nx) + 1;
int y = ((ni - 1) / gg->nx) + 1;
int i = ptr2int(e);
assert((x >= 1) && (x <= gg->nx));
assert((y >= 1) && (y <= gg->ny));
switch (i) {
case 1: /* right */
if (gg->right && (x != gg->nx))
ei->to = &gg->sg.nodes[ni + 1];
break;
case 2: /* down */
if (gg->down && (y != gg->ny))
ei->to = &gg->sg.nodes[ni + gg->nx];
break;
case 3: /* left */
if (gg->left && (x != 1))
ei->to = &gg->sg.nodes[ni - 1];
break;
case 4: /* up */
if (gg->up && (y != 1))
ei->to = &gg->sg.nodes[ni - gg->nx];
break;
default:
assert(0);
}
return 0;
}
void grid_graph_init(struct grid_graph *gg, int nx, int ny,
bool right, bool down, bool left, bool up)
{
assert((nx * ny) < MAX_NODES);
gg->nx = nx;
gg->ny = ny;
gg->right = right;
gg->down = down;
gg->left = left;
gg->up = up;
simple_graph_init(&gg->sg, grid_first_edge, grid_next_edge,
grid_edge_info);
}
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