system
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Topic was automatically imported from the old Question2Answer platform. 

Asked By 
Dentrax 
Hello,
I am implementing a simple spawner in 2D mode. My aim is to make them (each node) spawn with a 30degree angle.
In Unity, I can solve this problem via Euler.
Vector2 v = Vector2.zero  base.transform.position;
v = Quaternion.Euler(0f, 0f, 30f) * v;
In Godot, how can I create a function that is exactly equivalent?
Currently, my implementation is:
var vector = target.position  position
var right = Quat(Vector3(vector.x, vector.y, 0), 30);
var left = Quat(Vector3(vector.x, vector.y, 0), 30);
if index == 1:
vector.x = right.get_euler().x * vector.x;
vector.y = right.get_euler().y * vector.y;
elif index == 2:
vector.x = left.get_euler().x * vector.x;
vector.y = left.get_euler().y * vector.y;
But it works wrong. The ‘left’ is throwing the back side and the angle of both ‘left’ and ‘right’ is not 30 degrees.
system
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Reply From: 
hammeron 
You can rotate a vector with a Transform2D.
Also note that angles in Godot are in radians.
var m = Transform2D().rotated(deg2rad(30));
# Clockwise rotation
var new_pos = m * vector;
# Counterclockwise
new_pos = m.xform_inv(vector);
Indepth explanation about Transforms: Matrices and transforms — Godot Engine (3.1) documentation in English
Thank you it’s working fine.
Dentrax  20190404 10:35
system
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Reply From: 
brainbug 
var q = Quat()
q.set_euler(Vector3(yaw,tilt,roll))
v = q * v
the angles must be in radians!!
Well, how can i change the (x, y) at the same time with the given angle via Euler?
vector = get_rotated_vector(vector, 35)
Like this:
func get_rotated_vector(vector, degrees):
var sinr = sin(degrees * PI/180);
var cosr = cos(degrees * PI/180);
vector.x = (cosr * vector.x)  (sinr * vector.y);
vector.y = (sinr * vector.x) + (cosr * vector.y);
return vector;
P.S: I get this code from StackOverflow, I couldn’t find the source, sorry.
Dentrax  20190404 10:42