From 420b84da5f73084b51c78e9bdae9881cad67ef21 Mon Sep 17 00:00:00 2001
From: perivesta <>
Date: Sun, 9 Jul 2023 14:49:46 +0200
Subject: new car physics

---
 Nodes/Level_test.tscn    |  2 --
 Nodes/Level_test_2.tscn  |  2 --
 Nodes/car.tscn           |  1 +
 Scripts/car_behaviour.gd | 45 ++++++++++++++++++++++++++++++++++++---------
 4 files changed, 37 insertions(+), 13 deletions(-)

diff --git a/Nodes/Level_test.tscn b/Nodes/Level_test.tscn
index 6e2c195..d512420 100644
--- a/Nodes/Level_test.tscn
+++ b/Nodes/Level_test.tscn
@@ -35,8 +35,6 @@ texture = ExtResource("2_gp6ng")
 shape = SubResource("CircleShape2D_6g88q")
 
 [node name="Car" parent="." instance=ExtResource("4_xvobs")]
-max_speed = 500
-acceleration = 0.05
 
 [node name="DrawNode" type="Node2D" parent="."]
 script = ExtResource("5_x7h3g")
diff --git a/Nodes/Level_test_2.tscn b/Nodes/Level_test_2.tscn
index df32fcd..fff7252 100644
--- a/Nodes/Level_test_2.tscn
+++ b/Nodes/Level_test_2.tscn
@@ -35,8 +35,6 @@ texture = ExtResource("4_1x7qu")
 shape = SubResource("CircleShape2D_6g88q")
 
 [node name="Car" parent="." instance=ExtResource("5_vbxx6")]
-max_speed = 500
-acceleration = 0.05
 
 [node name="DrawNode" type="Node2D" parent="."]
 script = ExtResource("6_6cnd6")
diff --git a/Nodes/car.tscn b/Nodes/car.tscn
index dbfb4e1..98b68ac 100644
--- a/Nodes/car.tscn
+++ b/Nodes/car.tscn
@@ -15,3 +15,4 @@ texture = SubResource("CanvasTexture_aacgf")
 
 [node name="CollisionShape2D" type="CollisionShape2D" parent="."]
 shape = SubResource("RectangleShape2D_wvlyu")
+debug_color = Color(0.916191, 7.77793e-05, 0.710129, 0.42)
diff --git a/Scripts/car_behaviour.gd b/Scripts/car_behaviour.gd
index 2ef9fb9..8c22bf3 100644
--- a/Scripts/car_behaviour.gd
+++ b/Scripts/car_behaviour.gd
@@ -1,9 +1,10 @@
 extends CharacterBody2D
 
 # editor variables
-@export var max_speed = 300
-@export var steer_force = 0.1
-@export var acceleration = 0.0
+@export var max_speed = 800
+@export var steer_force = 20
+@export var acceleration = 8
+@export var mass = 1.0
 @export var look_ahead = 75
 @export var num_rays = 32
 @export var driving = false
@@ -35,8 +36,9 @@ func _physics_process(delta):
 	set_danger()
 	choose_direction()
 	
-	# example_movement(delta)
-	own_movement(delta)
+#	example_movement(delta)
+#	own_movement(delta)
+	own_movement_improved(delta)
 
 
 func set_interest():
@@ -91,13 +93,38 @@ func example_movement(delta):
 	rotation = velocity.angle()
 	move_and_collide(velocity * delta)
 
+
 func own_movement(delta):
 	var desired_velocity = chosen_dir.rotated(rotation) * max_speed
+
+	var new_speed = lerpf(velocity.length(), max_speed, acceleration)
+	var new_angle = lerp_angle(velocity.angle(), desired_velocity.angle(), steer_force)
+	
+	velocity = Vector2.from_angle(new_angle) * new_speed
+	rotation = new_angle
+	move_and_collide(velocity * delta)
+	
+
+func own_movement_improved(delta):
+	var desired_velocity = chosen_dir.rotated(rotation) * max_speed
+	print('==========')
+	print('current speed: ', velocity.length(), ' | current angle: ', velocity.angle())
+	print('desired speed: ', desired_velocity.length(), ' | desired angle: ', desired_velocity.angle())
 	
-	var actual_speed = lerpf(velocity.length(), max_speed, acceleration)
-	var actual_angle = lerp_angle(velocity.angle(), desired_velocity.angle(), steer_force)
+#	var possible_radius = mass * velocity.length_squared() / steer_force
+#	var possible_steer_angle = velocity.length() / possible_radius
+	var possible_steer_angle = steer_force / (mass * velocity.length())
+	var angle_change = clampf(wrapf(desired_velocity.angle() - velocity.angle(), -PI, PI), -possible_steer_angle, possible_steer_angle)
+	var new_angle = wrapf(velocity.angle() + angle_change, -PI, PI)
+	print('possible_steer_angle: ', possible_steer_angle, ' | angle_change: ', angle_change, ' | new_angle: ', new_angle )
 	
-	velocity = Vector2.from_angle(actual_angle) * actual_speed
-	rotation = actual_angle
+	var wanted_speed = steer_force / (mass * absf(desired_velocity.angle() - velocity.angle()))
+	var new_max_speed = min(velocity.length() + (acceleration), max_speed)
+	var new_min_speed = max(velocity.length() - (acceleration), 0)
+	var new_speed = clampf(wanted_speed, new_min_speed, new_max_speed)
+	print('wanted: ', wanted_speed, ' | min: ', new_min_speed, ' | max: ', new_max_speed, ' | new: ', new_speed)
 	
+	velocity = Vector2.from_angle(new_angle) * new_speed
+	rotation = new_angle
 	move_and_collide(velocity * delta)
+
-- 
cgit