monsters: improve following and wandering behaviour

Makes monsters wander around the player they're following when nearby,
and wander towards the player using the follow update interval when
further away.
This prevents them clustering tightly around the player and increases
their chance of overcoming trivial obstacles.

Fixes trying to walk into walls.

diff --git a/qcsrc/common/monsters/sv_monsters.qc b/qcsrc/common/monsters/sv_monsters.qc
index 7f00250fbf781a13a32572c71dc193b6bb483ba6..d516aec2c109b62b572aa2b56e4ab5ee56c06563 100644 (file)
--- a/qcsrc/common/monsters/sv_monsters.qc
+++ b/qcsrc/common/monsters/sv_monsters.qc
@@ -575,6 +575,27 @@ void Monster_Use(entity this, entity actor, entity trigger)
        if(Monster_ValidTarget(this, actor, true)) { this.enemy = actor; }
 }
 
+/// Returns an origin that's near targetorigin and visible to this monster.
+vector Monster_WanderTarget(entity this, vector targetorigin)
+{
+       vector pos, ang;
+
+       ang_y = rint(random() * 500);
+       ang_x = this.angles_x;
+       ang_z = this.angles_z;
+       makevectors(ang);
+       pos = targetorigin + v_forward * this.wander_distance;
+       if(((this.flags & FL_FLY) && (this.spawnflags & MONSTERFLAG_FLY_VERTICAL)) || (this.flags & FL_SWIM))
+       {
+               pos.z = random() * 200;
+               if(random() >= 0.5)
+                       pos.z *= -1;
+       }
+       // truncate movement so we don't do walking into walls animations
+       traceline(this.origin + this.view_ofs, pos, MOVE_NORMAL, this);
+       return trace_endpos;
+}
+
 vector Monster_Move_Target(entity this, entity targ)
 {
        // enemy is always preferred target
@@ -610,7 +631,14 @@ vector Monster_Move_Target(entity this, entity targ)
                {
                        this.monster_movestate = MONSTER_MOVE_FOLLOW;
                        this.last_trace = time + 0.3;
-                       return (this.monster_follow) ? this.monster_follow.origin : this.origin;
+                       if (this.monster_follow)
+                       {
+                               if (vdist(this.origin - this.monster_follow.origin, <, this.wander_distance))
+                                       this.last_trace = time + this.wander_delay;
+                               return Monster_WanderTarget(this, this.monster_follow.origin);
+                       }
+                       else
+                               return this.origin;
                }
                case MONSTER_MOVE_SPAWNLOC:
                {
@@ -635,36 +663,22 @@ vector Monster_Move_Target(entity this, entity targ)
                default:
                case MONSTER_MOVE_WANDER:
                {
-                       vector pos;
                        this.monster_movestate = MONSTER_MOVE_WANDER;
-
                        if(this.monster_moveto)
                        {
                                this.last_trace = time + 0.5;
-                               pos = this.monster_moveto;
+                               return this.monster_moveto;
                        }
                        else if(targ)
                        {
                                this.last_trace = time + 0.5;
-                               pos = targ.origin;
+                               return targ.origin;
                        }
                        else
                        {
                                this.last_trace = time + this.wander_delay;
-
-                               this.angles_y = rint(random() * 500);
-                               makevectors(this.angles);
-                               pos = this.origin + v_forward * this.wander_distance;
-
-                               if(((this.flags & FL_FLY) && (this.spawnflags & MONSTERFLAG_FLY_VERTICAL)) || (this.flags & FL_SWIM))
-                               {
-                                       pos.z = random() * 200;
-                                       if(random() >= 0.5)
-                                               pos.z *= -1;
-                               }
+                               return Monster_WanderTarget(this, this.origin);
                        }
-
-                       return pos;
                }
        }
 }