How does move_and_slide() use move_and_collide() under the hood?

system · September 4, 2022, 5:30pm


	Attention	Topic was automatically imported from the old Question2Answer platform.
	Asked By	lakshaya

Hi,

I’m trying to make my 2DKinematic Character as controllable as possible.

In order to do this, I want to use move_and_collide(), and write my own logic for handling collisions.

I’m running into quite a few issues, as everything doesn’t just work with a magic wand via this method. It would be very helpful to see how move_and_slide() uses move_and_collide().

Can anybody help me with this? Are there any C#/C++ docs?

system · September 4, 2022, 5:33pm


	Reply From:	kidscancode

The “C++ docs” are the source code. You can see how move_and_slide() is implemented by looking at the source:

github.com

godotengine/godot/blob/3.5/scene/2d/physics_body_2d.cpp#L1121


      
          		gt.elements[2] += result.motion;
          		set_global_transform(gt);
          	}
          
          	return colliding;
          }
          
          //so, if you pass 45 as limit, avoid numerical precision errors when angle is 45.
          #define FLOOR_ANGLE_THRESHOLD 0.01
          
          Vector2 KinematicBody2D::_move_and_slide_internal(const Vector2 &p_linear_velocity, const Vector2 &p_snap, const Vector2 &p_up_direction, bool p_stop_on_slope, int p_max_slides, float p_floor_max_angle, bool p_infinite_inertia) {
          	Vector2 body_velocity = p_linear_velocity;
          	Vector2 body_velocity_normal = body_velocity.normalized();
          	Vector2 up_direction = p_up_direction.normalized();
          	bool was_on_floor = on_floor;
          
          	// Hack in order to work with calling from _process as well as from _physics_process; calling from thread is risky
          	float delta = Engine::get_singleton()->is_in_physics_frame() ? get_physics_process_delta_time() : get_process_delta_time();
          
          	Vector2 current_floor_velocity = floor_velocity;
          	if (on_floor && on_floor_body.is_valid()) {