Server: Add explanatory comments to build_fov_map().

[plomrogue] / src / server / field_of_view.c

diff --git a/src/server/field_of_view.c b/src/server/field_of_view.c
index b4303970cdee2bcb283ed223aa5a6832f3ca0cb2..9cd52d01a51f17f9bccfb5acd47eee7ec5fe398f 100644 (file)
--- a/src/server/field_of_view.c
+++ b/src/server/field_of_view.c
@@ -6,9 +6,9 @@
 #include <string.h> /* memset() */
 #include "../common/rexit.h" /* exit_trouble() */
 #include "../common/try_malloc.h" /* try_malloc() */
+#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 "yx_uint8.h" /* yx_uint8, mv_yx_in_hex_dir(), mv_yx_in_dir_wrap(), */
 #include "world.h" /* world  */
 
 
@@ -317,34 +317,35 @@ extern void build_fov_map(struct Thing * t)
     memset(t->fov_map, 'v', map_size);
     struct shadow_angle * shadows = NULL;
     struct yx_uint8 test_pos = t->pos;
-    char * circle_dirs = "xswedc";
-    uint16_t dist;
-    uint8_t circle_on_map;
-    for (dist = 1, circle_on_map = 1; circle_on_map; dist++)
+    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++)
     {
-        if (1 != dist)
+        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.   */
+        uint8_t dir_char_pos_in_circledirs_string = 0;
+        char dir_char = 'd'; /* Circle's 1st hex is entered by rightward move.*/
+        uint16_t dist_i, hex_i;
+        for (hex_i = 0, dist_i = 1; hex_i < 6 * circle_i; dist_i++, hex_i++)
         {
-            mv_yx_in_dir_legal('c', &test_pos);
-        }
-        char dir = 'd';
-        uint8_t i_dir = 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++)
-        {
-            if (mv_yx_in_dir_legal(dir, &test_pos))
-            {
-                eval_position(dist, hex_i, t->fov_map, &test_pos, &shadows);
-                circle_on_map = 1;
-            }
-            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;
             }
+            dir_char = circledirs_string[dir_char_pos_in_circledirs_string];
+            if (circle_i == dist_i)                 /* Number of steps into   */
+            {                                       /* one direction before   */
+                dist_i = 0;                         /* direction change is    */
+                dir_char_pos_in_circledirs_string++;/* equal to distance to   */
+            }                                       /* center / circle number.*/
         }
     }
-    mv_yx_in_dir_wrap(0, NULL, 1);
+    mv_yx_in_dir_legal(0, NULL);
     free_angles(shadows);
     update_map_memory(t, map_size);
 }