-Made one way collision work with 2D physics (rigidbody)

demos/2d/platformer/one_way_platform.xml

@@ -0,0 +1,220 @@
+<?xml version="1.0" encoding="UTF-8" ?>
+<resource_file type="PackedScene" subresource_count="3" version="1.1" version_name="Godot Engine v1.1.rc1.custom_build">
+	<ext_resource path="res://one_way_platform.png" type="Texture"></ext_resource>
+	<resource type="RectangleShape2D" path="local://1">
+		<real name="custom_solver_bias"> 0 </real>
+		<vector2 name="extents"> 100, 10 </vector2>
+
+	</resource>
+	<main_resource>
+		<dictionary name="_bundled" shared="false">
+			<string> "conn_count" </string>
+			<int> 0 </int>
+			<string> "conns" </string>
+			<int_array  len="0"> 				 </int_array>
+			<string> "names" </string>
+			<string_array  len="42">
+				<string> "one_way_platform" </string>
+				<string> "StaticBody2D" </string>
+				<string> "_import_path" </string>
+				<string> "visibility/visible" </string>
+				<string> "visibility/opacity" </string>
+				<string> "visibility/self_opacity" </string>
+				<string> "visibility/light_mask" </string>
+				<string> "transform/pos" </string>
+				<string> "transform/rot" </string>
+				<string> "transform/scale" </string>
+				<string> "z/z" </string>
+				<string> "z/relative" </string>
+				<string> "input/pickable" </string>
+				<string> "shape_count" </string>
+				<string> "shapes/0/shape" </string>
+				<string> "shapes/0/transform" </string>
+				<string> "shapes/0/trigger" </string>
+				<string> "collision/layers" </string>
+				<string> "collision/mask" </string>
+				<string> "one_way_collision/direction" </string>
+				<string> "one_way_collision/max_depth" </string>
+				<string> "constant_linear_velocity" </string>
+				<string> "constant_angular_velocity" </string>
+				<string> "friction" </string>
+				<string> "bounce" </string>
+				<string> "__meta__" </string>
+				<string> "sprite" </string>
+				<string> "Sprite" </string>
+				<string> "texture" </string>
+				<string> "centered" </string>
+				<string> "offset" </string>
+				<string> "flip_h" </string>
+				<string> "flip_v" </string>
+				<string> "vframes" </string>
+				<string> "hframes" </string>
+				<string> "frame" </string>
+				<string> "modulate" </string>
+				<string> "region" </string>
+				<string> "region_rect" </string>
+				<string> "CollisionShape2D" </string>
+				<string> "shape" </string>
+				<string> "trigger" </string>
+			</string_array>
+			<string> "node_count" </string>
+			<int> 3 </int>
+			<string> "nodes" </string>
+			<int_array  len="135"> 				-1, -1, 1, 0, -1, 24, 2, 0, 3, 1, 4, 2, 5, 2, 6, 3, 7, 4, 8, 5, 9, 6, 10, 7, 11, 1, 12, 8, 13, 3, 14, 9, 15, 10, 16, 8, 17, 3, 18, 3, 19, 11, 20, 12, 21, 4, 22, 5, 23, 2, 24, 5, 25, 13, 0, 0, 0, 27, 26, -1, 21, 2, 0, 3, 1, 4, 2, 5, 2, 6, 3, 7, 4, 8, 5, 9, 6, 10, 7, 11, 1, 28, 14, 29, 1, 30, 4, 31, 8, 32, 8, 33, 3, 34, 3, 35, 7, 36, 15, 37, 8, 38, 16, 0, 0, 0, 39, 39, -1, 12, 2, 0, 3, 1, 4, 2, 5, 2, 6, 3, 7, 17, 8, 5, 9, 6, 10, 7, 11, 1, 40, 9, 41, 8, 0 </int_array>
+			<string> "variants" </string>
+			<array  len="18" shared="false">
+				<node_path> "" </node_path>
+				<bool> True </bool>
+				<real> 1 </real>
+				<int> 1 </int>
+				<vector2> 0, 0 </vector2>
+				<real> 0 </real>
+				<vector2> 1, 1 </vector2>
+				<int> 0 </int>
+				<bool> False </bool>
+				<resource  resource_type="Shape2D" path="local://1">  </resource>
+				<matrix32> 1, -0, 0, 1, 1.46304, -13.1672 </matrix32>
+				<vector2> 0, 1 </vector2>
+				<real> 20 </real>
+				<dictionary  shared="false">
+					<string> "__editor_plugin_screen__" </string>
+					<string> "2D" </string>
+					<string> "__editor_plugin_states__" </string>
+					<dictionary  shared="false">
+						<string> "2D" </string>
+						<dictionary  shared="false">
+							<string> "ofs" </string>
+							<vector2> -133.699, -110.553 </vector2>
+							<string> "snap_grid" </string>
+							<bool> False </bool>
+							<string> "snap_offset" </string>
+							<vector2> 0, 0 </vector2>
+							<string> "snap_pixel" </string>
+							<bool> False </bool>
+							<string> "snap_relative" </string>
+							<bool> False </bool>
+							<string> "snap_rotation" </string>
+							<bool> False </bool>
+							<string> "snap_rotation_offset" </string>
+							<real> 0 </real>
+							<string> "snap_rotation_step" </string>
+							<real> 0.261799 </real>
+							<string> "snap_show_grid" </string>
+							<bool> False </bool>
+							<string> "snap_step" </string>
+							<vector2> 10, 10 </vector2>
+							<string> "zoom" </string>
+							<real> 2.050546 </real>
+						</dictionary>
+						<string> "3D" </string>
+						<dictionary  shared="false">
+							<string> "ambient_light_color" </string>
+							<color> 0.15, 0.15, 0.15, 1 </color>
+							<string> "default_light" </string>
+							<bool> True </bool>
+							<string> "default_srgb" </string>
+							<bool> False </bool>
+							<string> "deflight_rot_x" </string>
+							<real> 0.942478 </real>
+							<string> "deflight_rot_y" </string>
+							<real> 0.628319 </real>
+							<string> "fov" </string>
+							<real> 45 </real>
+							<string> "show_grid" </string>
+							<bool> True </bool>
+							<string> "show_origin" </string>
+							<bool> True </bool>
+							<string> "viewport_mode" </string>
+							<int> 1 </int>
+							<string> "viewports" </string>
+							<array  len="4" shared="false">
+								<dictionary  shared="false">
+									<string> "distance" </string>
+									<real> 4 </real>
+									<string> "listener" </string>
+									<bool> True </bool>
+									<string> "pos" </string>
+									<vector3> 0, 0, 0 </vector3>
+									<string> "use_environment" </string>
+									<bool> False </bool>
+									<string> "use_orthogonal" </string>
+									<bool> False </bool>
+									<string> "x_rot" </string>
+									<real> 0 </real>
+									<string> "y_rot" </string>
+									<real> 0 </real>
+								</dictionary>
+								<dictionary  shared="false">
+									<string> "distance" </string>
+									<real> 4 </real>
+									<string> "listener" </string>
+									<bool> False </bool>
+									<string> "pos" </string>
+									<vector3> 0, 0, 0 </vector3>
+									<string> "use_environment" </string>
+									<bool> False </bool>
+									<string> "use_orthogonal" </string>
+									<bool> False </bool>
+									<string> "x_rot" </string>
+									<real> 0 </real>
+									<string> "y_rot" </string>
+									<real> 0 </real>
+								</dictionary>
+								<dictionary  shared="false">
+									<string> "distance" </string>
+									<real> 4 </real>
+									<string> "listener" </string>
+									<bool> False </bool>
+									<string> "pos" </string>
+									<vector3> 0, 0, 0 </vector3>
+									<string> "use_environment" </string>
+									<bool> False </bool>
+									<string> "use_orthogonal" </string>
+									<bool> False </bool>
+									<string> "x_rot" </string>
+									<real> 0 </real>
+									<string> "y_rot" </string>
+									<real> 0 </real>
+								</dictionary>
+								<dictionary  shared="false">
+									<string> "distance" </string>
+									<real> 4 </real>
+									<string> "listener" </string>
+									<bool> False </bool>
+									<string> "pos" </string>
+									<vector3> 0, 0, 0 </vector3>
+									<string> "use_environment" </string>
+									<bool> False </bool>
+									<string> "use_orthogonal" </string>
+									<bool> False </bool>
+									<string> "x_rot" </string>
+									<real> 0 </real>
+									<string> "y_rot" </string>
+									<real> 0 </real>
+								</dictionary>
+							</array>
+							<string> "zfar" </string>
+							<real> 500 </real>
+							<string> "znear" </string>
+							<real> 0.1 </real>
+						</dictionary>
+					</dictionary>
+					<string> "__editor_run_settings__" </string>
+					<dictionary  shared="false">
+						<string> "custom_args" </string>
+						<string> "-l $scene" </string>
+						<string> "run_mode" </string>
+						<int> 0 </int>
+					</dictionary>
+				</dictionary>
+				<resource  resource_type="Texture" path="res://one_way_platform.png">  </resource>
+				<color> 1, 1, 1, 1 </color>
+				<rect2> 0, 0, 0, 0 </rect2>
+				<vector2> 1.46304, -13.1672 </vector2>
+			</array>
+			<string> "version" </string>
+			<int> 1 </int>
+		</dictionary>
+
+	</main_resource>
+</resource_file>

servers/physics_2d/body_2d_sw.cpp

@@ -657,6 +657,7 @@ Body2DSW::Body2DSW() : CollisionObject2DSW(TYPE_BODY), active_list(this), inerti
 	area_linear_damp=0;
 	contact_count=0;
 	gravity_scale=1.0;
+	using_one_way_cache=false;
 	one_way_collision_max_depth=0.1;
 
 	still_time=0;

servers/physics_2d/body_2d_sw.h

@@ -81,6 +81,7 @@ class Body2DSW : public CollisionObject2DSW {
 	bool active;
 	bool can_sleep;
 	bool first_time_kinematic;
+	bool using_one_way_cache;
 	void _update_inertia();
 	virtual void _shapes_changed();
 	Matrix32 new_transform;
@@ -229,12 +230,17 @@ public:
 	_FORCE_INLINE_ void set_continuous_collision_detection_mode(Physics2DServer::CCDMode p_mode) { continuous_cd_mode=p_mode; }
 	_FORCE_INLINE_ Physics2DServer::CCDMode get_continuous_collision_detection_mode() const { return continuous_cd_mode; }
 
-	void set_one_way_collision_direction(const Vector2& p_dir) { one_way_collision_direction=p_dir; }
+	void set_one_way_collision_direction(const Vector2& p_dir) {
+		one_way_collision_direction=p_dir;
+		using_one_way_cache=one_way_collision_direction!=Vector2();
+	}
 	Vector2 get_one_way_collision_direction() const { return one_way_collision_direction; }
 
 	void set_one_way_collision_max_depth(float p_depth) { one_way_collision_max_depth=p_depth; }
 	float get_one_way_collision_max_depth() const { return one_way_collision_max_depth; }
 
+	_FORCE_INLINE_ bool is_using_one_way_collision() const { return using_one_way_cache; }
+
 	void set_space(Space2DSW *p_space);
 
 	void update_inertias();

servers/physics_2d/body_pair_2d_sw.cpp

@@ -265,6 +265,8 @@ bool BodyPair2DSW::setup(float p_step) {
 	} 
 	//faster to set than to check..
 
+	bool prev_collided=collided;
+
 	collided = CollisionSolver2DSW::solve(shape_A_ptr,xform_A,motion_A,shape_B_ptr,xform_B,motion_B,_add_contact,this,&sep_axis);
 	if (!collided) {
 
@@ -285,6 +287,57 @@ bool BodyPair2DSW::setup(float p_step) {
 
 	}
 
+	if (!prev_collided) {
+
+		if (A->is_using_one_way_collision()) {
+			Vector2 direction = A->get_one_way_collision_direction();
+			bool valid=false;
+			for(int i=0;i<contact_count;i++) {
+				Contact& c = contacts[i];
+
+				if (c.normal.dot(direction)<0)
+					continue;
+				if (B->get_linear_velocity().dot(direction)<0)
+					continue;
+
+				if (!c.reused) {
+					continue;
+				}
+
+				valid=true;
+			}
+
+			if (!valid) {
+				collided=false;
+				return false;
+			}
+		}
+
+		if (B->is_using_one_way_collision()) {
+			Vector2 direction = B->get_one_way_collision_direction();
+			bool valid=false;
+			for(int i=0;i<contact_count;i++) {
+
+				Contact& c = contacts[i];
+
+				if (c.normal.dot(direction)<0)
+					continue;
+				if (A->get_linear_velocity().dot(direction)<0)
+					continue;
+
+				if (!c.reused) {
+					continue;
+				}
+
+				valid=true;
+			}
+			if (!valid) {
+				collided=false;
+				return false;
+			}
+		}
+	}
+
 	real_t max_penetration = space->get_contact_max_allowed_penetration();
 
 	float bias = 0.3f;