AI Prototype
This is an AI state machine prototype. The pathfinding is not the best, but I simply wanted to focus on the various detection zones and behaviour for an enemy.
CONTROLS
- WASD = Control player.
- Mouse / Left Click = Aim / Shoot.
- Shift (hold) + WASD = Run.
- + = Spawn more enemies.
- T = toggle debug info on and off.
- R = Reset room
BROAD DESIGN
- Will patrol and occasionally change directions until detecting the player.
- When detecting the player, will try to get within shooting range and shoot.
- When losing sight of the player, will get to their last known position and return to patrol if it can't find the player.
- If enemy health falls too low, the enemy will flee the player when detecting them.
- Only one enemy is allowed to shoot at the player at once (token system).
MAIN BEHAVIOUR SCRIPT (sample)
#region // DETECTION LOOP
if !collision_line(x, y, oPlayer.x, oPlayer.y, oWall, true, true) {
lastknown_x = oPlayer.x;
lastknown_y = oPlayer.y;
// See when near
if point_in_triangle(oPlayer.x, oPlayer.y, x, y, sight_detect_near_cone_x1, sight_detect_near_cone_y1, sight_detect_near_cone_x2, sight_detect_near_cone_y2) {
player_is_detected = true;
}
// See from far when player is walking
else if point_in_triangle(oPlayer.x, oPlayer.y, x, y, sight_detect_far_cone_x1, sight_detect_far_cone_y1, sight_detect_far_cone_x2, sight_detect_far_cone_y2) and oPlayer.is_walking {
player_is_detected = true;
}
// Hear the player from really close
else if point_in_circle(oPlayer.x, oPlayer.y, x, y, hear_detect_near_radius) {
player_is_detected = true;
}
// Hear the player from near if player is walking
else if point_in_circle(oPlayer.x, oPlayer.y, x, y, hear_detect_walk_radius) and oPlayer.is_walking {
player_is_detected = true;
}
// Hear the player from far if player is running
else if point_in_circle(oPlayer.x, oPlayer.y, x, y, hear_detect_run_radius) and oPlayer.is_walking and oPlayer.is_running {
player_is_detected = true;
}
else {
player_is_detected = false;
}
}
else {
player_is_detected = false;
}
#endregion
#region // STATE LOOP
if (hp >= flee_theshold and player_is_detected) or (hp >= flee_theshold and alarm[1] > 0) {
state = "CHASE";
mp_potential_step_object(lastknown_x, lastknown_y, chase_speed, oWall);
if point_distance(x, y, oPlayer.x, oPlayer.y) < shoot_threshold and can_shoot and (global.token < global.maxtoken or is_shooting) {
if !is_shooting {
global.token = global.token + 1;
is_shooting = true;
}
can_shoot = false;
instance_create_depth(x, y, depth, oBulletEnemy);
alarm[2] = shoot_delay;
}
}
else if (hp < flee_theshold and player_is_detected) or (hp < flee_theshold and alarm[1] > 0) {
state = "FLEE";
if is_shooting {
is_shooting = false;
global.token = global.token - 1;
}
direction = point_direction(x, y, oPlayer.x, oPlayer.y) + 180;
speed = flee_speed;
}
else if !player_is_detected and state != "PATROL" {
state = "PATROL";
if is_shooting {
is_shooting = false;
global.token = global.token - 1;
}
direction = choose(0, 90, 180, 270);
speed = patrol_speed;
alarm[0] = change_direction;
}
#endregion
