Windows Rotate an Object around its Centre

[Angelos]

I am trying to rotate the following object around its own centre.
I saw there is a way to do it on every frame, but I want to make the player change its rotation with the left (anticlockwise) and right (clockwise) direction keys.
Any advice please?
Thanks in advance!

 

[jo-thijs]

I am trying to rotate the following object around its own centre.
I saw there is a way to do it on every frame, but I want to make the player change its rotation with the left (anticlockwise) and right (clockwise) direction keys.
Any advice please?
Thanks in advance!
View attachment 22411

Hi and welcome to the GMC!

Objects in GameMaker have a built-in variable "image_angle", which automatically rotates the sprite of the instance around the origin of the sprite when drawn.

In GML, to rotate an instance 5 degrees clockwise when holding the right arrow key
and 5 degrees counterclockwise when holding the left arrow key, you can put the following in the step event of the rotating object:

var input = keyboard_check(vk_right) - keyboard_check(vk_left);

image_angle -= input * 5;

 

[Angelos]

Thank you very much for your code and your time!

 

[AlexDerFerri]

if you want to rotate an object around a point, you can do something like this:

// oSun CREATE EVENT
rotation_speed = 5;
angle = 0;
distance_from_centre = 64;
centre_x = room_width/2;
centre_y = room_height/2;

/// oSun STEP EVENT

var input = (keyboard_check(vk_right) - keyboard_check(vk_left));

angle += (input * rotation_speed);

x = centre_x + lengthdir_x(distance_from_centre, angle);
y = centre_y + lengthdir_y(distance_from_centre, angle);


if you have multiple planets you can have a oPlanetParent object with the code written above.
Then make oSun and oEarth and whatever planet you have inherit from the oPlanetParent object.