-/* src/server/field_of_view.c */
+/* src/server/field_of_view.c
+ *
+ * This file is part of PlomRogue. PlomRogue is licensed under the GPL version 3
+ * or any later version. For details on its copyright, license, and warranties,
+ * see the file NOTICE in the root directory of the PlomRogue source package.
+ */
#include "field_of_view.h"
-#include <stdint.h> /* uint8_t, uint16_t, uint32_t, int32_t */
+#include <stddef.h> /* NULL */
+#include <stdint.h> /* uint8_t, uint16_t, uint32_t, int32_t, UINT8_MAX */
#include <stdlib.h> /* free() */
#include <string.h> /* memset() */
#include "../common/rexit.h" /* exit_trouble() */
#include "../common/try_malloc.h" /* try_malloc() */
-#include "map.h" /* yx_to_map_pos() */
-#include "things.h" /* Thing */
-#include "yx_uint8.h" /* yx_uint8 */
+#include "../common/yx_uint8.h" /* yx_uint8 */
+#include "map.h" /* mv_yx_in_dir_legal() */
+#include "things.h" /* Thing, ThingInMemory, add_thing_to_memory_map() */
#include "world.h" /* world */
-/* Move "yx" into hex direction "d". */
-static void mv_yx_in_hex_dir(char d, struct yx_uint8 * yx);
-
-/* Move "yx" into hex direction "d". If this moves "yx" beyond the minimal (0)
- * or maximal (UINT8_MAX) column or row, it wraps to the opposite side. Such
- * wrapping is returned as a wraps enum value and stored, so that further calls
- * to move "yx" back into the opposite direction may unwrap it again. Pass an
- * "unwrap" of !0 to re-set the internal wrap memory to 0.
- */
-static uint8_t mv_yx_in_dir_wrap(char d, struct yx_uint8 * yx, uint8_t unwrap);
-
-/* Wrapper to mv_yx_in_dir_wrap(), returns 1 if the wrapped function moved "yx"
- * within the wrap borders and the map size, else 0.
- */
-static uint8_t mv_yx_in_dir_legal(char dir, struct yx_uint8 * yx);
-
/* Recalculate angle < 0 or > CIRCLE to a value between these two limits. */
static uint32_t correct_angle(int32_t angle);
static uint8_t try_merging_angles(uint32_t left_angle, uint32_t right_angle,
struct shadow_angle ** shadows);
-/* If "pos_in_map" in angle between"left_angle" to "right_angle" to the viewing
- * actor is in a shadow from the shadow list "shadows", mark it as HIDDEN on the
- * "fov_map"; else, if the world map features a viewing obstacle on the world
- * map, calculate its shadow angle to the viewer and add it to "shadows".
+/* Test whether angle between "left_angle" and "right_angle", or at least
+ * "middle_angle", is captured inside one of the shadow angles in "shadows". If
+ * so, set hex in "fov_map" indexed by "pos_in_map" to 'H'. If the whole angle
+ * and not just "middle_angle" is captured, return 1. Any other case: 0.
*/
-static void set_shadow(uint32_t left_angle, uint32_t right_angle,
- struct shadow_angle ** shadows, uint16_t pos_in_map,
- uint8_t * fov_map);
+static uint8_t shade_hex(uint32_t left_angle, uint32_t right_angle,
+ uint32_t middle_angle, struct shadow_angle ** shadows,
+ uint16_t pos_in_map, char * fov_map);
/* Free shadow angles list "angles". */
static void free_angles(struct shadow_angle * angles);
/* Evaluate map position "test_pos" in distance "dist" to the view origin, and
* on the circle of that distance to the origin on hex "hex_i" (as counted from
- * the circle's rightmost point), for setting shaded cells in "fov_map" and
+ * the circle's rightmost point), for setting shaded hexes in "fov_map" and
* potentially adding a new shadow to linked shadow angle list "shadows".
*/
-static void eval_position(uint16_t dist, uint16_t hex_i, uint8_t * fov_map,
+static void eval_position(uint16_t dist, uint16_t hex_i, char * fov_map,
struct yx_uint8 * test_pos,
struct shadow_angle ** shadows);
-
-
-static void mv_yx_in_hex_dir(char d, struct yx_uint8 * yx)
-{
- if (d == 'e')
- {
- yx->x = yx->x + (yx->y % 2);
- yx->y--;
- }
- else if (d == 'd')
- {
- yx->x++;
- }
- else if (d == 'c')
- {
- yx->x = yx->x + (yx->y % 2);
- yx->y++;
- }
- else if (d == 'x')
- {
- yx->x = yx->x - !(yx->y % 2);
- yx->y++;
- }
- else if (d == 's')
- {
- yx->x--;
- }
- else if (d == 'w')
- {
- yx->x = yx->x - !(yx->y % 2);
- yx->y--;
- }
-}
-
-
-
-static uint8_t mv_yx_in_dir_wrap(char d, struct yx_uint8 * yx, uint8_t unwrap)
-{
- static int8_t wrap_west_east = 0;
- static int8_t wrap_north_south = 0;
- if (unwrap)
- {
- wrap_west_east = wrap_north_south = 0;
- return 0;
- }
- struct yx_uint8 original;
- original.y = yx->y;
- original.x = yx->x;
- mv_yx_in_hex_dir(d, yx);
- if (strchr("edc", d) && yx->x < original.x)
- {
- wrap_west_east++;
- }
- else if (strchr("xsw", d) && yx->x > original.x)
- {
- wrap_west_east--;
- }
- if (strchr("we", d) && yx->y > original.y)
- {
- wrap_north_south--;
- }
- else if (strchr("xc", d) && yx->y < original.y)
- {
- wrap_north_south++;
- }
- return (wrap_west_east != 0) + (wrap_north_south != 0);
-}
-
-
-
-static uint8_t mv_yx_in_dir_legal(char dir, struct yx_uint8 * yx)
-{
- uint8_t wraptest = mv_yx_in_dir_wrap(dir, yx, 0);
- if (!wraptest && yx->x < world.map.length && yx->y < world.map.length)
- {
- return 1;
- }
- return 0;
-}
+/* Update "t"'s .mem_map memory with what's in its current FOV, remove from its
+ * .t_mem all memorized things in FOV and add inanimiate things in FOV to it.
+ */
+static void update_map_memory(struct Thing * t, uint32_t map_size);
-static void set_shadow(uint32_t left_angle, uint32_t right_angle,
- struct shadow_angle ** shadows, uint16_t pos_in_map,
- uint8_t * fov_map)
+static uint8_t shade_hex(uint32_t left_angle, uint32_t right_angle,
+ uint32_t middle_angle, struct shadow_angle ** shadows,
+ uint16_t pos_in_map, char * fov_map)
{
struct shadow_angle * shadow_i;
- if (fov_map[pos_in_map] & VISIBLE)
+ if (fov_map[pos_in_map] == 'v')
{
for (shadow_i = *shadows; shadow_i; shadow_i = shadow_i->next)
{
if ( left_angle <= shadow_i->left_angle
&& right_angle >= shadow_i->right_angle)
{
- fov_map[pos_in_map] = HIDDEN;
- return;
+ fov_map[pos_in_map] = 'H';
+ return 1;
+ }
+ if ( middle_angle < shadow_i->left_angle
+ && middle_angle > shadow_i->right_angle)
+ {
+ fov_map[pos_in_map] = 'H';
}
}
}
- if ('X' == world.map.cells[pos_in_map])
+ return 0;
+}
+
+
+
+/* To "shadows", add shadow defined by "left_angle" and "right_angle", either as
+ * new entry or as part of an existing shadow (swallowed whole or extending it).
+ */
+static void set_shadow(uint32_t left_angle, uint32_t right_angle,
+ struct shadow_angle ** shadows)
+{
+ struct shadow_angle * shadow_i;
+ if (!try_merging_angles(left_angle, right_angle, shadows))
{
- if (!try_merging_angles(left_angle, right_angle, shadows))
+ struct shadow_angle * shadow;
+ shadow = try_malloc(sizeof(struct shadow_angle), __func__);
+ shadow->left_angle = left_angle;
+ shadow->right_angle = right_angle;
+ shadow->next = NULL;
+ if (*shadows)
{
- struct shadow_angle * shadow;
- shadow = try_malloc(sizeof(struct shadow_angle), __func__);
- shadow->left_angle = left_angle;
- shadow->right_angle = right_angle;
- shadow->next = NULL;
- if (*shadows)
+ for (shadow_i = *shadows; shadow_i; shadow_i = shadow_i->next)
{
- for (shadow_i = *shadows; shadow_i; shadow_i = shadow_i->next)
+ if (!shadow_i->next)
{
- if (!shadow_i->next)
- {
- shadow_i->next = shadow;
- return;
- }
+ shadow_i->next = shadow;
+ return;
}
}
- *shadows = shadow;
}
+ *shadows = shadow;
}
}
-static void eval_position(uint16_t dist, uint16_t hex_i, uint8_t * fov_map,
+static void eval_position(uint16_t dist, uint16_t hex_i, char * fov_map,
struct yx_uint8 * test_pos,
struct shadow_angle ** shadows)
{
int32_t left_angle_uncorrected = ((CIRCLE / 12) / dist)
- - ((hex_i * (CIRCLE / 6)) / dist);
+ - (hex_i * (CIRCLE / 6) / dist);
int32_t right_angle_uncorrected = left_angle_uncorrected
- (CIRCLE / (6 * dist));
uint32_t left_angle = correct_angle(left_angle_uncorrected);
uint32_t right_angle = correct_angle(right_angle_uncorrected);
uint32_t right_angle_1st = right_angle > left_angle ? 0 : right_angle;
- uint16_t pos_in_map = yx_to_map_pos(test_pos);
- set_shadow(left_angle, right_angle_1st, shadows, pos_in_map, fov_map);
- if (right_angle_1st != right_angle)
+ uint32_t middle_angle = 0;
+ if (right_angle_1st)
{
- left_angle = CIRCLE;
- set_shadow(left_angle, right_angle, shadows, pos_in_map, fov_map);
+ middle_angle = right_angle + ((left_angle - right_angle) / 2);
+ }
+ uint16_t pos_in_map = test_pos->y * world.map.length + test_pos->x;
+ uint8_t all_shaded = shade_hex(left_angle, right_angle_1st, middle_angle,
+ shadows, pos_in_map, fov_map);
+ if (!all_shaded && 'X' == world.map.cells[pos_in_map])
+ {
+ set_shadow(left_angle, right_angle_1st, shadows);
+ if (right_angle_1st != right_angle)
+ {
+ left_angle = CIRCLE;
+ set_shadow(left_angle, right_angle, shadows);
+ }
}
}
-extern uint8_t * build_fov_map(struct Thing * eye)
+static void update_map_memory(struct Thing * t_eye, uint32_t map_size)
{
- uint32_t map_size = world.map.length * world.map.length;
- uint8_t * fov_map = try_malloc(map_size, __func__);
- memset(fov_map, VISIBLE, map_size);
- struct yx_uint8 test_pos = eye->pos;
- struct shadow_angle * shadows = NULL;
- char * circle_dirs = "xswedc";
- uint16_t dist;
- uint8_t first_round, circle_on_map;
- for (first_round = 1, dist = 1, circle_on_map = 1; circle_on_map; dist++)
+ if (!t_eye->mem_map)
{
- if (!first_round)
+ t_eye->mem_map = try_malloc(map_size, __func__);
+ memset(t_eye->mem_map, ' ', map_size);
+ }
+ uint32_t i;
+ for (i = 0; i < map_size; i++)
+ {
+ if (' ' == t_eye->mem_map[i] && t_eye->fov_map[i] == 'v')
+ {
+ t_eye->mem_map[i] = world.map.cells[i];
+ }
+ }
+ struct ThingInMemory * tm = t_eye->t_mem;
+ struct ThingInMemory * tm_prev = NULL;
+ struct ThingInMemory * tm_next = NULL;
+ for (; tm; tm = tm_next)
+ {
+ tm_next = tm->next;
+ if ('v' == t_eye->fov_map[tm->pos.y * world.map.length + tm->pos.x])
{
- mv_yx_in_dir_legal('c', &test_pos);
+ if (tm_prev)
+ {
+ tm_prev->next = tm->next;
+ }
+ else
+ {
+ t_eye->t_mem = tm->next;
+ }
+ free(tm);
+ continue;
}
- char dir = 'd';
- uint8_t i_dir = first_round = circle_on_map = 0;
- uint16_t i_dist, hex_i;
- for (hex_i = 0, i_dist = 1; hex_i < 6 * dist; i_dist++, hex_i++)
+ tm_prev = tm;
+ }
+ struct Thing * t = world.things;
+ for (; t; t = t->next)
+ {
+ if ( !t->lifepoints
+ && 'v' == t_eye->fov_map[t->pos.y * world.map.length + t->pos.x])
+ {
+ add_thing_to_memory_map(t_eye, t->type, t->pos.y, t->pos.x);
+ }
+ }
+}
+
+
+
+extern void build_fov_map(struct Thing * t)
+{
+ uint32_t map_size = world.map.length * world.map.length;
+ t->fov_map = t->fov_map ? t->fov_map : try_malloc(map_size, __func__);
+ memset(t->fov_map, 'v', map_size);
+ struct shadow_angle * shadows = NULL;
+ struct yx_uint8 test_pos = t->pos;
+ char * circledirs_string = "xswedc";
+ uint16_t circle_i;
+ uint8_t circle_is_on_map;
+ for (circle_i = 1, circle_is_on_map = 1; circle_is_on_map; circle_i++)
+ {
+ circle_is_on_map = 0;
+ if (1 < circle_i) /* All circles but the 1st are */
+ { /* moved into starting from a */
+ mv_yx_in_dir_legal('c', &test_pos);/* previous circle's last hex, */
+ } /* i.e. from the upper left. */
+ char dir_char = 'd'; /* Circle's 1st hex is entered by rightward move.*/
+ uint8_t dir_char_pos_in_circledirs_string = UINT8_MAX;
+ uint16_t dist_i, hex_i;
+ for (hex_i=0, dist_i=circle_i; hex_i < 6 * circle_i; dist_i++, hex_i++)
{
- if (mv_yx_in_dir_legal(dir, &test_pos))
+ if (circle_i < dist_i)
{
- eval_position(dist, hex_i, fov_map, &test_pos, &shadows);
- circle_on_map = 1;
+ dist_i = 1;
+ dir_char=circledirs_string[++dir_char_pos_in_circledirs_string];
}
- dir = circle_dirs[i_dir];
- if (dist == i_dist)
+ if (mv_yx_in_dir_legal(dir_char, &test_pos))
{
- i_dist = 0;
- i_dir++;
+ eval_position(circle_i, hex_i, t->fov_map, &test_pos, &shadows);
+ circle_is_on_map = 1;
}
}
}
- mv_yx_in_dir_wrap(0, NULL, 1);
+ mv_yx_in_dir_legal(0, NULL);
free_angles(shadows);
- return fov_map;
+ update_map_memory(t, map_size);
}