Fix sliding while on planet by getting closest gravity

Materials/GasGiantMaterial.tres

@@ -3,7 +3,7 @@
 [ext_resource path="res://Resources/gas_planet_flowmap.png" type="Texture" id=1]
 [ext_resource path="res://Resources/gas_planet_base.png" type="Texture" id=2]
 
-[sub_resource type="Shader" id=14]
+[sub_resource type="Shader" id=1]
 resource_local_to_scene = true
 code = "shader_type spatial;
 
@@ -38,7 +38,7 @@ void fragment(){
 "
 
 [resource]
-shader = SubResource( 14 )
+shader = SubResource( 1 )
 shader_param/color = Color( 1, 0.890196, 0.172549, 1 )
 shader_param/flow_speed = 0.2
 shader_param/flow_intensity = 0.8

MovingPlatform.gd

@@ -31,7 +31,7 @@ func _process(delta):
 	velocity = (translation - translation_before) / delta
 	
 	# Rotate according to gravity
-	var gravity_acceleration = get_node(solar_system).get_gravitation_acceleration(global_transform.origin)
+	var gravity_acceleration = get_node(solar_system).get_gravity_acceleration(global_transform.origin)
 	
 	# Rotate down vector to face center of gravity
 	var down = gravity_acceleration

Planets.gd

@@ -13,7 +13,30 @@ const distance_multiplier = 318550   # thus, a radius of 20 results in an earth-
 const gravity_multiplier = 10.0
 
 
-func get_gravitation_acceleration(position: Vector3) -> Vector3:
+# Return the gravity acceleration vector to the closest planet, not taking all other planets into
+# account.
+# This is useful for keeping something firmly on the planet while it is touching it, or for creating
+# a predictable orbit.
+func get_closest_gravity_acceleration(position: Vector3) -> Vector3:
+	var closest_planet_distance = INF
+	var closest_force = 0.0
+	
+	for planet in get_children():
+		var pos_to_center = (planet.transform.origin - position)
+		var distance = pos_to_center.length()
+		
+		if distance < closest_planet_distance:
+			var force = _gravity(planet.mass * mass_multiplier, distance * distance_multiplier)
+			force *= gravity_multiplier
+			
+			closest_force = (pos_to_center / distance) * force
+			closest_planet_distance = distance
+	
+	return closest_force
+
+
+# Return the total gravity acceleration vector experienced at that position.
+func get_gravity_acceleration(position: Vector3) -> Vector3:
 	var total_force = Vector3.ZERO
 	
 	for planet in get_children():

Player.gd

@@ -63,13 +63,10 @@ func _physics_process(delta):
 	# Make movement local
 	move_acceleration = transform.basis * move_acceleration
 	
-	print(on_ground)
-	
 	# Jumping and Gravity
-	var gravity_acceleration = get_node(solar_system).get_gravitation_acceleration(transform.origin)
-	#if on_ground:
-		# FIXME: This breaks some things, but seems to be the right principle
-		#gravity_acceleration = Vector3.ZERO
+	var gravity_acceleration = get_node(solar_system).get_gravity_acceleration(transform.origin)
+	if $GroundCheckRay.is_colliding():
+		gravity_acceleration = get_node(solar_system).get_closest_gravity_acceleration(transform.origin)
 	
 	apply_acceleration((move_acceleration + gravity_acceleration) * delta)
 	

ShootyEnemy.gd

@@ -26,7 +26,7 @@ func _physics_process(delta):
 	)
 	
 	if target:
-		var gravity = solar_system.get_gravitation_acceleration(global_transform.origin)
+		var gravity = solar_system.get_gravity_acceleration(global_transform.origin)
 		look_at(target, gravity)
 	
 	global_transform.origin += velocity * delta