Add vehicle sounds and adjust RPM

scenes/test_level.tscn

@@ -35,7 +35,6 @@ shape = SubResource( 3 )
 [node name="buggy" parent="." instance=ExtResource( 1 )]
 transform = Transform( 1.00456, 0, 0, 0, 1.00456, 0, 0, 0, 1.00456, -38.0928, 1.38435, -0.0872202 )
 mass = 250.0
-STEER_SPEED = 1.5
 
 [node name="camera" type="Camera" parent="."]
 transform = Transform( 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 5.88022, 23.0639 )

vehicles/buggy.gd

@@ -14,19 +14,28 @@ export (Curve) var steer_curve = null
 var steer_target = 0.0
 var steer_angle = 0.0
 
-export (float) var MAX_ENGINE_FORCE = 50.0
+export (float) var MAX_ENGINE_FORCE = 85.0
 export (float) var MAX_BRAKE_FORCE = 50.0
-export (float) var THROTTLE_POWER = 10000.0
+export (float) var THROTTLE_POWER = 6000.0
 export (float) var MAX_RPM_LOSS_PS = 3000.0
 
-export (Array) var gear_ratios = [ 6, 5, 4, 3, 2, 1.0 ]
+export (Array) var gear_ratios = [ 3.4, 2.5, 2.0, 1.5, 1.25 ]
-export (float) var reverse_ratio = -6.0
+export (float) var reverse_ratio = -3
-export (float) var final_drive = 3.38
+export (float) var final_drive = 3.45
-export (float) var max_rpm = 7000
+export (float) var max_rpm = 3500
 export (float) var min_rpm = 900
 export (float) var gear_switch_time = 0.2
 export (Curve) var power_curve = null
 
+
+var idle_sound_start: float = 0.5
+var idle_sound_end: float = 1
+
+var throttle_sound_start: float = 2.5
+var throttle_sound_end: float = 3.5
+
+var sound_time_left: float = 0.0
+
 var clutch_position: float = 0.0
 var rpm = 0
 var gear = 1
@@ -38,6 +47,9 @@ onready var flwheel: VehicleWheel = $front_left
 onready var rrwheel: VehicleWheel = $rear_right
 onready var rlwheel: VehicleWheel = $rear_left
 
+onready var engine_sound_player: AudioStreamPlayer3D = $engine_sound_player
+onready var engine_sound_playback: AudioStreamPlayback = $engine_sound_player.get_stream_playback()
+
 var traction_wheels: Array
 
 func _ready():
@@ -45,6 +57,9 @@ func _ready():
 		if wheel.use_as_traction:
 			traction_wheels.append(wheel)
 
+	_generate_engine_sound(0)
+	engine_sound_player.play()
+
 func _get_gear_ratio():
 	if gear == 0:
 		return 0
@@ -90,9 +105,9 @@ func _physics_process(delta: float):
 
 	if gear != 0:
 		rpm = lerp(rpm, transmission_rpm, delta * (1 - clutch_position))
-		rpm = _lerp_rpm(rpm, min_rpm, delta, delta * clutch_position * 3)
+		rpm = _lerp_rpm(rpm, min_rpm, delta, delta * clutch_position)
 	else:
-		rpm = _lerp_rpm(rpm, min_rpm, delta, delta * 3)
+		rpm = _lerp_rpm(rpm, min_rpm, delta, delta)
 	if _has_traction():
 		rpm += throttle * delta * clutch_position * THROTTLE_POWER
 	else:
@@ -101,6 +116,8 @@ func _physics_process(delta: float):
 	var rpm_factor = clamp(rpm / max_rpm, 0.0, 1.0)
 	var power_factor = power_curve.interpolate_baked(rpm_factor)
 
+	_generate_engine_sound(rpm_factor)
+
 	# Transfer to transmission
 	var transmission_input = power_factor * (1 - clutch_position) * _get_gear_ratio()
 
@@ -114,7 +131,7 @@ func _physics_process(delta: float):
 	rlwheel.brake = handbrake * MAX_BRAKE_FORCE / 2
 
 	var speed = wheel_rpm * 2.0 * PI * rrwheel.wheel_radius / 60.0 * 3600.0 / 1000.0
-	$Info.text = "Gear: %d, KPH: %.0f, RPM: %.0f, TRPM: %.0f, Engine force: %.0f" % [ gear, speed, rpm, transmission_rpm, engine_force ]
+	$Info.text = "Gear: %d, KPH: %.0f, RPM: %.0f, WheelRPM: %.0f, FinalRPM: %.0f, TRPM: %.0f, Engine force: %.0f" % [ gear, speed, rpm, wheel_rpm, final_rpm, transmission_rpm, engine_force ]
 
 	var steering_input = Input.get_action_strength("steer_left") - Input.get_action_strength("steer_right")
 	if abs(steering_input) < 0.05:
@@ -129,3 +146,12 @@ func _physics_process(delta: float):
 
 	steer_angle = steering_input * lerp(max_steer_angle_rad, speed_steer_angle_rad, steer_speed_factor)
 	steering = steer_angle
+
+func _generate_engine_sound(rpm_factor):
+	engine_sound_player.pitch_scale = 0.5 + rpm_factor
+	var to_fill = engine_sound_playback.get_frames_available()
+	var factor = rpm_factor
+	while to_fill > 0:
+		engine_sound_playback.push_frame(Vector2(1.0, 1.0) * factor)
+		factor += cos(factor) * sin(factor)
+		to_fill -= 1

vehicles/buggy.tscn

@@ -1,17 +1,20 @@
-[gd_scene load_steps=5 format=2]
+[gd_scene load_steps=6 format=2]
 
 [ext_resource path="res://assets/basic_buggy.glb" type="PackedScene" id=1]
 [ext_resource path="res://vehicles/buggy.gd" type="Script" id=3]
 
 [sub_resource type="Curve" id=2]
-_data = [ Vector2( 0, 0 ), 0.0, 0.0, 0, 0, Vector2( 0.910377, 0.990909 ), 0.0, 0.0, 0, 0, Vector2( 1, 0 ), 0.0, 0.0, 0, 0 ]
+_data = [ Vector2( 0, 0 ), 0.0, 0.0, 0, 0, Vector2( 0.259434, 0.463636 ), 0.0, 0.0, 0, 0, Vector2( 0.59434, 0.872727 ), 0.0, 0.0, 0, 0, Vector2( 0.900943, 1 ), 0.0, 0.0, 0, 0, Vector2( 1, 0 ), 0.0, 0.0, 0, 0 ]
 
 [sub_resource type="BoxShape" id=1]
 extents = Vector3( 0.521885, 0.334919, 1.78849 )
 
+[sub_resource type="AudioStreamGenerator" id=3]
+mix_rate = 5500.0
+
 [node name="buggy" instance=ExtResource( 1 )]
+mass = 150.0
 script = ExtResource( 3 )
-STEER_SPEED = 1.5
 power_curve = SubResource( 2 )
 
 [node name="chassis" parent="." index="0"]
@@ -57,3 +60,8 @@ margin_bottom = 14.0
 __meta__ = {
 "_edit_use_anchors_": false
 }
+
+[node name="engine_sound_player" type="AudioStreamPlayer3D" parent="." index="8"]
+transform = Transform( 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 1.14201, 0.968668 )
+stream = SubResource( 3 )
+unit_db = 14.0

vehicles/buggy_test.tscn

@@ -8,7 +8,6 @@
 data = PoolVector3Array( -1, 1, 1, 1, 1, 1, -1, -1, 1, 1, 1, 1, 1, -1, 1, -1, -1, 1, 1, 1, -1, -1, 1, -1, 1, -1, -1, -1, 1, -1, -1, -1, -1, 1, -1, -1, 1, 1, 1, 1, 1, -1, 1, -1, 1, 1, 1, -1, 1, -1, -1, 1, -1, 1, -1, 1, -1, -1, 1, 1, -1, -1, -1, -1, 1, 1, -1, -1, 1, -1, -1, -1, 1, 1, 1, -1, 1, 1, 1, 1, -1, -1, 1, 1, -1, 1, -1, 1, 1, -1, -1, -1, 1, 1, -1, 1, -1, -1, -1, 1, -1, 1, 1, -1, -1, -1, -1, -1 )
 
 [node name="buggy" instance=ExtResource( 1 )]
-STEER_SPEED = 1.5
 
 [node name="Camera" type="Camera" parent="." index="7"]
 transform = Transform( -0.0903024, 0, -0.995914, 0, 1, 0, 0.995914, 0, -0.0903024, -3.4904, 1.22508, 0 )