Rotating with a surface normal

Help Programming
, ,
1

Godot Version

4.2.1

Question

i am trying to use godot’s physics output to do some sort of fake physical rotation in a racing game. so i have a vehicle, and i have deduced what direction the ‘ground’ is.

vehicle_0

the problem is that i need to be able to set my vehicle’s 3d body ‘rotation’ based on this information, and some sort of “direction”. since there are infinite rotations around this vector, my vehicle needs a consistent way to decide which one to face in.

vehicle_1

this is especially important in a racing game where i’ll be using the forward direction from this rotation to decide what direction the vehicle will drive in. so far i have been attempting to use look_at like so

$body.look_at(global_transform.origin + down_vector)

where $body is a child of my non-rotating rigidbody sphere node that contains the entire 3d model of the vehicle.

vehicle_2

using look_at obviously is producing inconsistent and unpredictable rotations, but it is successfully keeping my vehicle “flat” to the ground which is good. the problem is that it randomly rotates the vehicle’s body to some rotation around the surface normal axis. i need a way to make this rotation stay as consistent as possible, and then i need a way to use some ‘direction’ scalar to rotate the rotation around that axis. ideally changing this ‘direction’ will be how you turn.

vehicle_3

any thoughts on how to implement this? i’m a little overwhelmed by godot 3d rotation syntax, so maybe look_at isn’t the right function to use here. thanks

2

okay i think i actually figured it out

$body.look_at($body.global_position + down_vector,Vector3(cos(direction),0,-sin(direction)))

i just needed to use my direction to create an ‘up’ vector apparently. this feels scuffed but it works

3

This topic was automatically closed 30 days after the last reply. New replies are no longer allowed.