I’m new to defold and I’m trying to make an object point towards the mouse pointer.
Getting just the mouse coordinates would be very helpful too.
Hi @stainedmentor, and welcome!
I think the first step is to read our manual about input.
Pay special attention to the parts about Acquiring Input Focus, the on_input message handler and Mouse Triggers.
Those should be a good first step to your first input handling.
As for making an object rotate towards the mouse pointer, here is a good solution and demo by @britzl.
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Another demo and some code for the same thing:
http://britzl.github.io/publicexamples/rotate_and_move/index.html
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Ehmm, i saw this topic just and i dont really understand, i also need this code to my “plattformer” to get a go called gun to point towards the mouse
What exactly do you not understand?
I may just not have understand the answers by @Mathias_Westerdahl and @britzl or i am just bad at this. But, i dont understand Git-Hub
Hi man, I started a game recently and first thing I implemented is something like this. It’s still raw, but I guess it can be of help.
First in on_input function, create a vector from your character to the mouse. If you have a camera, you need to convert the characters position to screen first.
function on_input(self, action_id, action)
local pos = go.get_position()
pos = camera.world_to_screen(hash("/camera"), pos) -- convert position to screen
local mouse_vec = vmath.vector3(action.x - pos.x, action.y - pos.y, 0)
self.mouse_vec = mouse_vec
If you don’t have a camera, just use the position as go.get_position.
Once you have the vector from the player to the mouse, lets say your weapon object is child of your player. Update its position/rotation in your player’s update method like so:
-- update weapon position & rotation depending on mouse
if self.mouse_vec.y > 0 then
pos.z = 0.01 -- behind player
else
pos.z = 1 -- in front of player
end
local angle = math.atan2(self.mouse_vec.y, self.mouse_vec.x)
local rot = vmath.quat_rotation_z(angle)
if self.weapon then
sprite.set_vflip(self.weapon, rot.z > 0.65 or (rot.z < -0.5 and rot.z > -1)) -- flip if rotation reaches limit
go.set_position(pos, self.weapon)
go.set_rotation(rot, self.weapon)
end
-- end weapon pos & rot
Those vals are for a gun sprite pointing right. You should tweak the amounts, but I guess you can get a hang of what is going on by looking at the code.
The “pos” var has the players position. The vflip is for when the gun reaches a certain point that it has to be turned over for it to look natural. Hope it helps
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The relevant snippet of code:
local look_at = vmath.vector3(123, 456, 0) -- the position to look at
local my_position = go.get_position()
local angle = math.atan2(look_at.x - my_position.x, look_at.y - my_position.y)
go.set_rotation(vmath.quat_rotation_z(angle))
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