void init_walking(void)
{
CnetPosition start;
CHECK(CNET_set_handler(EV_WALKING, walker, 0));
choose_position(&start, 0);
CHECK(CNET_set_position(start));
}
void update_wolf(struct world **read_matrix, struct world **write_matrix, int row, int col) {
int possibilities[N_ADJACENTS];
int may_move[N_ADJACENTS];
int n_possibilities, n_squirrels, n_other;
int chosen;
struct world *wolf = &write_matrix[row][col];
n_possibilities = get_adjacents(row, col, possibilities);
if(!wolf->starvation_period) {
kill_wolf(wolf);
return;
}
/*If has adjacents to choose*/
if(n_possibilities) {
/*Check for squirrels*/
n_squirrels = get_cells_with_squirrels(read_matrix, possibilities, n_possibilities, may_move);
if(n_squirrels) {
/*At least one squirrel has been found
Choose one of them*/
chosen = choose_position(row, col, n_squirrels);
/* Eat the squirrel - Now inside move_to
get_world_coordinates(may_move[chosen], &s_row, &s_col);
eat_squirrel(wolf, &write_matrix[s_row][s_col]);*/
/*Move to that position*/
move_to(row, col, may_move[chosen], read_matrix, write_matrix);
}
else {
/*No squirrels
Let's another cell*/
n_other = get_walkable_cells(read_matrix, possibilities, n_possibilities, may_move, ICE | TREE);
if(n_other) {
chosen = choose_position(row, col, n_other);
/*Move to that position*/
move_to(row, col, may_move[chosen], read_matrix, write_matrix);
}
}
}
}
/*
* Update rules for animals in the world
*/
void update_squirrel(struct world **read_matrix, struct world **write_matrix, int row, int col) {
int possibilities[N_ADJACENTS];
int may_move[N_ADJACENTS];
int n_possibilities, n_moves;
int chosen;
n_possibilities = get_adjacents(row, col, possibilities);
n_moves = get_walkable_cells(read_matrix, possibilities, n_possibilities, may_move, ICE | WOLF);
if(n_moves) {
chosen = choose_position(row, col, n_moves);
move_to(row, col, may_move[chosen], read_matrix, write_matrix);
}
}
static EVENT_HANDLER(walker)
{
static double dx = 0.0;
static double dy = 0.0;
static double newx = 0.0;
static double newy = 0.0;
static int nsteps = 0;
CnetPosition now;
CnetTime movenext;
// IF PAUSED, WE NEED TO CHOOSE A NEW DESTINATION AND WALKING SPEED
if(paused) {
CnetPosition newdest;
CHECK(CNET_get_position(&now, NULL));
// CHOOSE A NEW DESTINATION THAT DOESN'T REQUIRE WALKING THROUGH A WALL!
do {
int newspeed;
double dist;
newdest = now;
do {
choose_position(&newdest, MAX_WALK_DIST);
} while(through_an_object(now, newdest));
dx = newdest.x - now.x;
dy = newdest.y - now.y;
dist = sqrt(dx*dx + dy*dy); // only walking in 2D
newspeed = CNET_rand() % MAX_SPEED + 1;
nsteps = dist / newspeed;
} while(nsteps < 3); // ensure we'll take at least 3 steps
//draw_walk(&now, &newdest);
// CALCULATE MOVEMENTS PER STEP
dx = (dx / nsteps);
dy = (dy / nsteps);
newx = now.x;
newy = now.y;
paused = false; // and off we go....
}
// WE'RE WALKING; DO WE STILL HAVE SOME STEPS TO TAKE?
if(nsteps > 0) {
newx += dx;
newy += dy;
now.x = newx;
now.y = newy;
now.z = 0;
CHECK(CNET_set_position(now));
paused = false;
--nsteps;
movenext = WALK_FREQUENCY;
}
// WE'VE FINISHED WALKING, SO WE PAUSE HERE FOR A WHILE
else {
paused = true;
nsteps = 0;
movenext = (CNET_rand() % (MAX_PAUSE-MIN_PAUSE) + MIN_PAUSE) * 1000000;
}
// RESCHEDULE THIS WALKING EVENT
tid = CNET_start_timer(EV_WALKING, movenext, data);
}