Restore RayShape as a regular shape type

Partial revert from previously removing ray shapes completely, added
back as a shape type but without the specific character controller code.

7 files changed, 148 insertions, 8 deletions

diff --git a/servers/physics_2d/collision_solver_2d_sat.cpp b/servers/physics_2d/collision_solver_2d_sat.cpp
index 30a99d3d74..3dde881c4d 100644
--- a/servers/physics_2d/collision_solver_2d_sat.cpp
+++ b/servers/physics_2d/collision_solver_2d_sat.cpp
@@ -1115,11 +1115,13 @@ bool sat_2d_calculate_penetration(const Shape2DSW *p_shape_A, const Transform2D
 	PhysicsServer2D::ShapeType type_A = p_shape_A->get_type();
 
 	ERR_FAIL_COND_V(type_A == PhysicsServer2D::SHAPE_WORLD_MARGIN, false);
+	ERR_FAIL_COND_V(type_A == PhysicsServer2D::SHAPE_RAY, false);
 	ERR_FAIL_COND_V(p_shape_A->is_concave(), false);
 
 	PhysicsServer2D::ShapeType type_B = p_shape_B->get_type();
 
 	ERR_FAIL_COND_V(type_B == PhysicsServer2D::SHAPE_WORLD_MARGIN, false);
+	ERR_FAIL_COND_V(type_B == PhysicsServer2D::SHAPE_RAY, false);
 	ERR_FAIL_COND_V(p_shape_B->is_concave(), false);
 
 	static const CollisionFunc collision_table[5][5] = {
@@ -1382,23 +1384,23 @@ bool sat_2d_calculate_penetration(const Shape2DSW *p_shape_A, const Transform2D
 
 	if (p_margin_A || p_margin_B) {
 		if (*motion_A == Vector2() && *motion_B == Vector2()) {
-			collision_func = collision_table_margin[type_A - 1][type_B - 1];
+			collision_func = collision_table_margin[type_A - 2][type_B - 2];
 		} else if (*motion_A != Vector2() && *motion_B == Vector2()) {
-			collision_func = collision_table_castA_margin[type_A - 1][type_B - 1];
+			collision_func = collision_table_castA_margin[type_A - 2][type_B - 2];
 		} else if (*motion_A == Vector2() && *motion_B != Vector2()) {
-			collision_func = collision_table_castB_margin[type_A - 1][type_B - 1];
+			collision_func = collision_table_castB_margin[type_A - 2][type_B - 2];
 		} else {
-			collision_func = collision_table_castA_castB_margin[type_A - 1][type_B - 1];
+			collision_func = collision_table_castA_castB_margin[type_A - 2][type_B - 2];
 		}
 	} else {
 		if (*motion_A == Vector2() && *motion_B == Vector2()) {
-			collision_func = collision_table[type_A - 1][type_B - 1];
+			collision_func = collision_table[type_A - 2][type_B - 2];
 		} else if (*motion_A != Vector2() && *motion_B == Vector2()) {
-			collision_func = collision_table_castA[type_A - 1][type_B - 1];
+			collision_func = collision_table_castA[type_A - 2][type_B - 2];
 		} else if (*motion_A == Vector2() && *motion_B != Vector2()) {
-			collision_func = collision_table_castB[type_A - 1][type_B - 1];
+			collision_func = collision_table_castB[type_A - 2][type_B - 2];
 		} else {
-			collision_func = collision_table_castA_castB[type_A - 1][type_B - 1];
+			collision_func = collision_table_castA_castB[type_A - 2][type_B - 2];
 		}
 	}
 
diff --git a/servers/physics_2d/collision_solver_2d_sw.cpp b/servers/physics_2d/collision_solver_2d_sw.cpp
index 8f8a4a862c..1946dae2e3 100644
--- a/servers/physics_2d/collision_solver_2d_sw.cpp
+++ b/servers/physics_2d/collision_solver_2d_sw.cpp
@@ -73,6 +73,49 @@ bool CollisionSolver2DSW::solve_static_world_margin(const Shape2DSW *p_shape_A,
 	return found;
 }
 
+bool CollisionSolver2DSW::solve_raycast(const Shape2DSW *p_shape_A, const Vector2 &p_motion_A, const Transform2D &p_transform_A, const Shape2DSW *p_shape_B, const Transform2D &p_transform_B, CallbackResult p_result_callback, void *p_userdata, bool p_swap_result, Vector2 *sep_axis) {
+	const RayShape2DSW *ray = static_cast<const RayShape2DSW *>(p_shape_A);
+	if (p_shape_B->get_type() == PhysicsServer2D::SHAPE_RAY) {
+		return false;
+	}
+
+	Vector2 from = p_transform_A.get_origin();
+	Vector2 to = from + p_transform_A[1] * ray->get_length();
+	if (p_motion_A != Vector2()) {
+		//not the best but should be enough
+		Vector2 normal = (to - from).normalized();
+		to += normal * MAX(0.0, normal.dot(p_motion_A));
+	}
+	Vector2 support_A = to;
+
+	Transform2D invb = p_transform_B.affine_inverse();
+	from = invb.xform(from);
+	to = invb.xform(to);
+
+	Vector2 p, n;
+	if (!p_shape_B->intersect_segment(from, to, p, n)) {
+		if (sep_axis) {
+			*sep_axis = p_transform_A[1].normalized();
+		}
+		return false;
+	}
+
+	Vector2 support_B = p_transform_B.xform(p);
+	if (ray->get_slips_on_slope()) {
+		Vector2 global_n = invb.basis_xform_inv(n).normalized();
+		support_B = support_A + (support_B - support_A).length() * global_n;
+	}
+
+	if (p_result_callback) {
+		if (p_swap_result) {
+			p_result_callback(support_B, support_A, p_userdata);
+		} else {
+			p_result_callback(support_A, support_B, p_userdata);
+		}
+	}
+	return true;
+}
+
 struct _ConcaveCollisionInfo2D {
 	const Transform2D *transform_A;
 	const Shape2DSW *shape_A;
@@ -177,6 +220,17 @@ bool CollisionSolver2DSW::solve(const Shape2DSW *p_shape_A, const Transform2D &p
 			return solve_static_world_margin(p_shape_A, p_transform_A, p_shape_B, p_transform_B, p_result_callback, p_userdata, false);
 		}
 
+	} else if (type_A == PhysicsServer2D::SHAPE_RAY) {
+		if (type_B == PhysicsServer2D::SHAPE_RAY) {
+			return false; //no ray-ray
+		}
+
+		if (swap) {
+			return solve_raycast(p_shape_B, p_motion_B, p_transform_B, p_shape_A, p_transform_A, p_result_callback, p_userdata, true, sep_axis);
+		} else {
+			return solve_raycast(p_shape_A, p_motion_A, p_transform_A, p_shape_B, p_transform_B, p_result_callback, p_userdata, false, sep_axis);
+		}
+
 	} else if (concave_B) {
 		if (concave_A) {
 			return false;
diff --git a/servers/physics_2d/physics_server_2d_sw.cpp b/servers/physics_2d/physics_server_2d_sw.cpp
index 88c097453e..0954f3a174 100644
--- a/servers/physics_2d/physics_server_2d_sw.cpp
+++ b/servers/physics_2d/physics_server_2d_sw.cpp
@@ -45,6 +45,9 @@ RID PhysicsServer2DSW::_shape_create(ShapeType p_shape) {
 		case SHAPE_WORLD_MARGIN: {
 			shape = memnew(WorldMarginShape2DSW);
 		} break;
+		case SHAPE_RAY: {
+			shape = memnew(RayShape2DSW);
+		} break;
 		case SHAPE_SEGMENT: {
 			shape = memnew(SegmentShape2DSW);
 		} break;
@@ -79,6 +82,10 @@ RID PhysicsServer2DSW::world_margin_shape_create() {
 	return _shape_create(SHAPE_WORLD_MARGIN);
 }
 
+RID PhysicsServer2DSW::ray_shape_create() {
+	return _shape_create(SHAPE_RAY);
+}
+
 RID PhysicsServer2DSW::segment_shape_create() {
 	return _shape_create(SHAPE_SEGMENT);
 }
diff --git a/servers/physics_2d/physics_server_2d_sw.h b/servers/physics_2d/physics_server_2d_sw.h
index 3610f43f93..1926eaac84 100644
--- a/servers/physics_2d/physics_server_2d_sw.h
+++ b/servers/physics_2d/physics_server_2d_sw.h
@@ -88,6 +88,7 @@ public:
 	};
 
 	virtual RID world_margin_shape_create() override;
+	virtual RID ray_shape_create() override;
 	virtual RID segment_shape_create() override;
 	virtual RID circle_shape_create() override;
 	virtual RID rectangle_shape_create() override;
diff --git a/servers/physics_2d/physics_server_2d_wrap_mt.h b/servers/physics_2d/physics_server_2d_wrap_mt.h
index b93178919d..0ebccc2614 100644
--- a/servers/physics_2d/physics_server_2d_wrap_mt.h
+++ b/servers/physics_2d/physics_server_2d_wrap_mt.h
@@ -80,6 +80,7 @@ public:
 
 	//FUNC1RID(shape,ShapeType); todo fix
 	FUNCRID(world_margin_shape)
+	FUNCRID(ray_shape)
 	FUNCRID(segment_shape)
 	FUNCRID(circle_shape)
 	FUNCRID(rectangle_shape)
diff --git a/servers/physics_2d/shape_2d_sw.cpp b/servers/physics_2d/shape_2d_sw.cpp
index b3e4ca84c3..be2f83b705 100644
--- a/servers/physics_2d/shape_2d_sw.cpp
+++ b/servers/physics_2d/shape_2d_sw.cpp
@@ -143,6 +143,46 @@ Variant WorldMarginShape2DSW::get_data() const {
 /*********************************************************/
 /*********************************************************/
 
+void RayShape2DSW::get_supports(const Vector2 &p_normal, Vector2 *r_supports, int &r_amount) const {
+	r_amount = 1;
+
+	if (p_normal.y > 0) {
+		*r_supports = Vector2(0, length);
+	} else {
+		*r_supports = Vector2();
+	}
+}
+
+bool RayShape2DSW::contains_point(const Vector2 &p_point) const {
+	return false;
+}
+
+bool RayShape2DSW::intersect_segment(const Vector2 &p_begin, const Vector2 &p_end, Vector2 &r_point, Vector2 &r_normal) const {
+	return false; //rays can't be intersected
+}
+
+real_t RayShape2DSW::get_moment_of_inertia(real_t p_mass, const Size2 &p_scale) const {
+	return 0; //rays are mass-less
+}
+
+void RayShape2DSW::set_data(const Variant &p_data) {
+	Dictionary d = p_data;
+	length = d["length"];
+	slips_on_slope = d["slips_on_slope"];
+	configure(Rect2(0, 0, 0.001, length));
+}
+
+Variant RayShape2DSW::get_data() const {
+	Dictionary d;
+	d["length"] = length;
+	d["slips_on_slope"] = slips_on_slope;
+	return d;
+}
+
+/*********************************************************/
+/*********************************************************/
+/*********************************************************/
+
 void SegmentShape2DSW::get_supports(const Vector2 &p_normal, Vector2 *r_supports, int &r_amount) const {
 	if (Math::abs(p_normal.dot(n)) > _SEGMENT_IS_VALID_SUPPORT_THRESHOLD) {
 		r_supports[0] = a;
diff --git a/servers/physics_2d/shape_2d_sw.h b/servers/physics_2d/shape_2d_sw.h
index 45d3379dfa..d1640b39cf 100644
--- a/servers/physics_2d/shape_2d_sw.h
+++ b/servers/physics_2d/shape_2d_sw.h
@@ -177,6 +177,41 @@ public:
 	}
 };
 
+class RayShape2DSW : public Shape2DSW {
+	real_t length;
+	bool slips_on_slope;
+
+public:
+	_FORCE_INLINE_ real_t get_length() const { return length; }
+	_FORCE_INLINE_ bool get_slips_on_slope() const { return slips_on_slope; }
+
+	virtual PhysicsServer2D::ShapeType get_type() const { return PhysicsServer2D::SHAPE_RAY; }
+
+	virtual void project_rangev(const Vector2 &p_normal, const Transform2D &p_transform, real_t &r_min, real_t &r_max) const { project_range(p_normal, p_transform, r_min, r_max); }
+	virtual void get_supports(const Vector2 &p_normal, Vector2 *r_supports, int &r_amount) const;
+
+	virtual bool contains_point(const Vector2 &p_point) const;
+	virtual bool intersect_segment(const Vector2 &p_begin, const Vector2 &p_end, Vector2 &r_point, Vector2 &r_normal) const;
+	virtual real_t get_moment_of_inertia(real_t p_mass, const Size2 &p_scale) const;
+
+	virtual void set_data(const Variant &p_data);
+	virtual Variant get_data() const;
+
+	_FORCE_INLINE_ void project_range(const Vector2 &p_normal, const Transform2D &p_transform, real_t &r_min, real_t &r_max) const {
+		//real large
+		r_max = p_normal.dot(p_transform.get_origin());
+		r_min = p_normal.dot(p_transform.xform(Vector2(0, length)));
+		if (r_max < r_min) {
+			SWAP(r_max, r_min);
+		}
+	}
+
+	DEFAULT_PROJECT_RANGE_CAST
+
+	_FORCE_INLINE_ RayShape2DSW() {}
+	_FORCE_INLINE_ RayShape2DSW(real_t p_length) { length = p_length; }
+};
+
 class SegmentShape2DSW : public Shape2DSW {
 	Vector2 a;
 	Vector2 b;