Expose value of idle circling with 'attack-any' (scp-fs2open#7011)

* Expose value of idle circling with 'attack-any'

The attack-any order is extremely useful and utilized order, and there was one aspect that was ripe for exposure to modders: the `CHASE_CIRCLE_DIST` that was used to determine how big of a circle to fly around while the AI waited for new hostiles to arrive. For ships with high speeds, like FotG and others, the default radius of 200 m was a bit on the small side, which lead to ships flying in tight circles. This was was counterproductive to goals of tuning the AI to have a more cinematic style, such as where AI would fly around in large distances while waiting for enemies to arrive. Fortunately, this value is easy to expose and allow modders to tune with just a new ai_profiles value.

Tested and works as expected.

* improve name and use correct distance

Author: wookieejedi

code/ai/ai_profiles.cpp

@@ -699,6 +699,10 @@ void parse_ai_profiles_tbl(const char *filename)
 					}
 				}
 
+				if (optional_string("$attack-any idle circle distance:")) {
+					stuff_float(&profile->attack_any_idle_circle_distance);
+				}
+
 				set_flag(profile, "$unify usage of AI Shield Manage Delay:", AI::Profile_Flags::Unify_usage_ai_shield_manage_delay);
 
 				set_flag(profile, "$fix AI shield management bug:", AI::Profile_Flags::Fix_AI_shield_management_bug);
@@ -815,6 +819,7 @@ void ai_profile_t::reset()
 
 	guard_big_orbit_above_target_radius = 500.0f;
 	guard_big_orbit_max_speed_percent = 1.0f;
+	attack_any_idle_circle_distance = 100.0f;
 
     for (int i = 0; i < NUM_SKILL_LEVELS; ++i) {
         max_incoming_asteroids[i] = 0;

code/ai/ai_profiles.h

@@ -144,6 +144,9 @@ class ai_profile_t {
 	float guard_big_orbit_above_target_radius; // Radius of guardee that triggers ai_big_guard() 
 	float guard_big_orbit_max_speed_percent;   // Max percent of forward speed that is used in ai_big_guard() 
 
+	// AI attack any option --wookieejedi
+	float attack_any_idle_circle_distance; // Radius that AI circles around a point while waiting for new enemies in attack-any mode
+
     void reset();
 };
 

code/ai/aicode.cpp

@@ -13244,8 +13244,6 @@ static void ai_preprocess_ignore_objnum(ai_info *aip)
 		aip->target_objnum = -1;
 }
 
-#define	CHASE_CIRCLE_DIST		100.0f
-
 void ai_chase_circle(object *objp)
 {
 	float		dist_to_goal;
@@ -13266,11 +13264,11 @@ void ai_chase_circle(object *objp)
 	if (aip->ignore_objnum == UNUSED_OBJNUM) {
 		dist_to_goal = vm_vec_dist_quick(&aip->goal_point, &objp->pos);
 
-		if (dist_to_goal > 2*CHASE_CIRCLE_DIST) {
+		if (dist_to_goal > 2 * The_mission.ai_profile->attack_any_idle_circle_distance) {
 			vec3d	vec_to_goal;
 			//	Too far from circle goal, create a new goal point.
 			vm_vec_normalized_dir(&vec_to_goal, &aip->goal_point, &objp->pos);
-			vm_vec_scale_add(&aip->goal_point, &objp->pos, &vec_to_goal, CHASE_CIRCLE_DIST);
+			vm_vec_scale_add(&aip->goal_point, &objp->pos, &vec_to_goal, The_mission.ai_profile->attack_any_idle_circle_distance);
 		}
 
 		goal_point = aip->goal_point;