Initial commit

original/rogue/p_trail.c

@@ -0,0 +1,129 @@
+// Copyright (c) ZeniMax Media Inc.
+// Licensed under the GNU General Public License 2.0.
+#include "g_local.h"
+
+
+/*
+==============================================================================
+
+PLAYER TRAIL
+
+==============================================================================
+
+This is a circular list containing the a list of points of where
+the player has been recently.  It is used by monsters for pursuit.
+
+.origin		the spot
+.owner		forward link
+.aiment		backward link
+*/
+
+
+#define	TRAIL_LENGTH	8
+
+edict_t		*trail[TRAIL_LENGTH];
+int			trail_head;
+qboolean	trail_active = false;
+
+#define NEXT(n)		(((n) + 1) & (TRAIL_LENGTH - 1))
+#define PREV(n)		(((n) - 1) & (TRAIL_LENGTH - 1))
+
+
+void PlayerTrail_Init (void)
+{
+	int		n;
+
+	if (deathmatch->value /* FIXME || coop */)
+		return;
+
+	for (n = 0; n < TRAIL_LENGTH; n++)
+	{
+		trail[n] = G_Spawn();
+		trail[n]->classname = "player_trail";
+	}
+
+	trail_head = 0;
+	trail_active = true;
+}
+
+
+void PlayerTrail_Add (vec3_t spot)
+{
+	vec3_t	temp;
+
+	if (!trail_active)
+		return;
+
+	VectorCopy (spot, trail[trail_head]->s.origin);
+
+	trail[trail_head]->timestamp = level.time;
+
+	VectorSubtract (spot, trail[PREV(trail_head)]->s.origin, temp);
+	trail[trail_head]->s.angles[1] = vectoyaw (temp);
+
+	trail_head = NEXT(trail_head);
+}
+
+
+void PlayerTrail_New (vec3_t spot)
+{
+	if (!trail_active)
+		return;
+
+	PlayerTrail_Init ();
+	PlayerTrail_Add (spot);
+}
+
+
+edict_t *PlayerTrail_PickFirst (edict_t *self)
+{
+	int		marker;
+	int		n;
+
+	if (!trail_active)
+		return NULL;
+
+	for (marker = trail_head, n = TRAIL_LENGTH; n; n--)
+	{
+		if(trail[marker]->timestamp <= self->monsterinfo.trail_time)
+			marker = NEXT(marker);
+		else
+			break;
+	}
+
+	if (visible(self, trail[marker]))
+	{
+		return trail[marker];
+	}
+
+	if (visible(self, trail[PREV(marker)]))
+	{
+		return trail[PREV(marker)];
+	}
+
+	return trail[marker];
+}
+
+edict_t *PlayerTrail_PickNext (edict_t *self)
+{
+	int		marker;
+	int		n;
+
+	if (!trail_active)
+		return NULL;
+
+	for (marker = trail_head, n = TRAIL_LENGTH; n; n--)
+	{
+		if(trail[marker]->timestamp <= self->monsterinfo.trail_time)
+			marker = NEXT(marker);
+		else
+			break;
+	}
+
+	return trail[marker];
+}
+
+edict_t *PlayerTrail_LastSpot (void)
+{
+	return trail[PREV(trail_head)];
+}