How to make accelerated movement effected by rotation

RenoKurnia

Hello i am new to game development and i am trying to make my first game with top-down perspective and now i'm trying to make the node movement effected by its current rotation, i already tried to rotated the movement directly with its rotation but it doesnt end well, and i end up with code similar to this:

velocity = Vector2()#this line somehow make thing work
target_speed = 0
if Input.is_action_pressed('ui_up'):
	target_speed = speed
	sailing = true
if Input.is_action_pressed('ui_down'):
	target_speed = -speed/2
	sailing = true
velocity.x = target_speed
velocity = velocity.rotated(rotation)

its work but now i want to make the node to accelerate, and make the code like this:

target_speed = 0
if Input.is_action_pressed('ui_up'):
	target_speed = speed
	sailing = true
if Input.is_action_pressed('ui_down'):
	target_speed = -speed/2
	sailing = true
velocity.x = lerp(velocity.x,target_speed,0.1)
velocity = velocity.rotated(rotation)

but end up with weird movement,it does accelerating though, and i think the "velocity = Vector2()" code is the one make thing work is there any way to make the node accelerating while effected by the rotation?, i have searching through internet but still doesnt find the solution.

RenoKurnia

i've tried something like this:

target_speed = 0
if Input.is_action_pressed('ui_up'):
	target_speed = speed
	sailing = true
elif Input.is_action_pressed('ui_down'):
	target_speed = -speed/2
	sailing = true
target_speed = lerp(velocity.x,target_speed,0.1)
velocity = Vector2(target_speed,0).rotated(rotation)

but still doesnt fix the problem, it does rotated correctly and accelerating but when the rotation is more than 30 or less than -30 the node goes slower and slower, the velocity.x value also reduced

TwistedTwigleg

Have you tried using the rotation of the Node2D when you are changing target_speed? Something like this (untested):

target_speed = 0
if Input.is_action_pressed(‘ui_up’):
	target_speed = Vector2( cos(rotation), sin(rotation) ) * speed
	sailing = true
elif Input.is_action_pressed(‘ui_dwn’):
	target_speed = Vector2( cos(rotation), sin(rotation) ) * -speed
	sailing = true
“Not 100% sure the line below will work”
velocity = velocity.linear_interpolate(velocity + target_speed, 0.1)

That way you do not need to rotate target_speed or velocity to move relative to the rotation of the Node2D

(For moving left/right, you just need to add/subtract 90 degrees of rotation. For example: target_speed = Vector2( cos(rotation + deg2rad(90) ), sin(rotation + deg2rad(90) ) ) * speed)

Edit: Just realized the initial code I posted would have not worked. I fixed it.

RenoKurnia

thank you!, your code giving me some hint, though your code above didnt work well, i tried something like this based on your code and work perfectly for me

target_velocity = Vector2(0,0)
target_speed = 0
if int(velocity.x)==0:
	sailing = false
if Input.is_action_pressed('ui_up'):
	target_speed = speed
	sailing = true
elif Input.is_action_pressed('ui_down'):
	target_speed = -speed/2
	sailing = true
target_velocity = Vector2(target_speed,0).rotated(rotation)
velocity = velocity.linear_interpolate(target_velocity,0.1)

this code does gave me the action that i want