Server: Add ENEMY_FOV option (default: off) to force FOV on enemies.

[plomrogue] / src / server / field_of_view.h

diff --git a/src/server/field_of_view.h b/src/server/field_of_view.h
index eb117ae4f7cbacbdb408dd198faead5ef7924931..ee337eb1d69636d4d95e764c685a94cc02d5e99b 100644 (file)
--- a/src/server/field_of_view.h
+++ b/src/server/field_of_view.h
@@ -1,6 +1,6 @@
 /* src/server/field_of_view.h
  *
- * Generate view of map as visible to player.
+ * Generate field of view maps.
  */
 
 
@@ -8,12 +8,38 @@
 #ifndef FIELD_OF_VIEW_H
 #define FIELD_OF_VIEW_H
 
+#include <stdint.h> /* uint8_t */
+struct MapObj;
 
 
-/* Return map cells sequence as visible to the player, with invisible cells as
- * whitespace. Super-impose over visible map cells map objects positioned there.
+
+/* States that cells in the fov map may be in. */
+enum fov_cell_states {
+    VISIBLE      = 0x01,
+    HIDDEN       = 0x02,
+    SHADOW_LEFT  = 0x04,
+    SHADOW_RIGHT = 0x08,
+    LIMIT        = 0x10,
+    HIDE_LATER   = 0x20
+};
+
+/* Return overlay of world map wherein all cell positions visible from player's
+ * positions have flag VISIBLE set.
+ *
+ * This is achieved by spiraling out clock-wise from the player position,
+ * flagging cells as VISIBLE unless they're already marked as HIDDEN, and, on
+ * running into obstacles for view that are not HIDDEN, casting shadows from
+ * these, i.e. drawing cells as HIDDEN that would be hidden by said obstacle,
+ * before continuing the original spiraling path.
+ *
+ * Shadowcasting during spiraling is initially lazy, flagging only the shadows'
+ * interior cells as HIDDEN and their border cells as HIDE_LATER. Only at the
+ * end are all cells flagged HIDE_LATER flagged as HIDDEN. This is to handle
+ * cases where obstacles to view sit right at the border of pre-estabilshed
+ * shadows, therefore might be ignored if HIDDEN and not cast shadows on their
+ * own that may slightly extend beyond the pre-established shadows they border.
  */
-extern char * build_visible_map();
+extern uint8_t * build_fov_map(struct MapObj * eye);