/*
 *  File:       los.h
 *  Summary:    Line-of-sight algorithm.
 */

#ifndef LOS_H
#define LOS_H

#include "externs.h"
#include "losparam.h"

#define EPSILON_VALUE 0.00001

bool double_is_zero(const double x);


void setLOSRadius(int newLR);
int get_los_radius_squared(); // XXX

struct ray_def;
bool find_ray(const coord_def& source, const coord_def& target,
              ray_def& ray, int cycle_dir = 0, bool find_shortest = false,
              bool ignore_solid = false);
void fallback_ray(const coord_def& source, const coord_def& target,
                  ray_def& ray);

int num_feats_between(const coord_def& source, const coord_def& target,
                      dungeon_feature_type min_feat,
                      dungeon_feature_type max_feat,
                      bool exclude_endpoints = true,
                      bool just_check = false);
bool cell_see_cell(const coord_def& p1, const coord_def& p2);

void clear_rays_on_exit();
void losight(env_show_grid& sh, const los_param& dat);
void calc_show_los();

bool see_grid( const env_show_grid &show,
               const coord_def &c,
               const coord_def &pos );
bool see_grid(const coord_def &p);
bool see_grid_no_trans( const coord_def &p );
bool trans_wall_blocking( const coord_def &p );

inline bool see_grid( int grx, int gry )
{
    return see_grid(coord_def(grx, gry));
}

inline bool see_grid_no_trans(int x, int y)
{
    return see_grid_no_trans(coord_def(x, y));
}

inline bool trans_wall_blocking(int x, int y)
{
    return trans_wall_blocking(coord_def(x, y));
}

#endif