Camera2D zoom & smoothing problem

[FEDE0D]

When the camera2D is moving and the zoom is updated, the camera movement makes a "stop" and then continues. Note this only occurs when using a smoothing factor other than 0.

I'm using dynamic changes in the camera properties using the Tween class and this is very noticeable. I don't know if this only applies to zoom only or other properties as well.

I include a test project: https://dl.dropboxusercontent.com/u/274954519/bugZoom2D.zip
Use LEFT-RIGHT to move and 1, 2, 3 to set the zoom.
Notice how the speed of the camera changes, even when setting the same zoom multiple times. Also, everything seems to work fine if the smoothing is 0

[guilhermefelipecgs]

I don't think this is a bug, I changed your code a little and I think it's pretty good now. try it.

extends KinematicBody2D

var zoom = Vector2(1, 1)
var old_zoom

func _ready():
    set_fixed_process(true)

func _fixed_process(delta):
    if Input.is_action_pressed("ui_left"):
        move(Vector2(-400 * delta, 0))
    if Input.is_action_pressed("ui_right"):
        move(Vector2(400 * delta, 0))

    old_zoom = zoom

    if Input.is_action_pressed("zoom_1"):
        zoom = Vector2(1, 1)
    if Input.is_action_pressed("zoom_2"):
        zoom = Vector2(1.5, 1.5)
    if Input.is_action_pressed("zoom_3"):
        zoom = Vector2(2, 2)

    if old_zoom != zoom:
        get_node("Camera2D").set_zoom(zoom)

[guilhermefelipecgs]

Maybe this only hide the bug, I dunno, but the result is very better.

[FEDE0D]

This only hides the bug.
That snippet code was just for showing the bug.
On my oroject I was using several Cameras and using Tween to change the values of the main cam to one of the others for a smothing transition. This bug hold me back from doing that.

[guilhermefelipecgs]

Strange, I was thinking that this error is because the key press was calling the set_zoom often, but I tried this way and it's working fine.
original code with bug:

...
if Input.is_action_pressed("zoom_1"):
    get_node("Camera2D").set_zoom(Vector2(1, 1))
if Input.is_action_pressed("zoom_2"):
    get_node("Camera2D").set_zoom(Vector2(1.5, 1.5))
if Input.is_action_pressed("zoom_3"):
    get_node("Camera2D").set_zoom(Vector2(2, 2))

new code:

var zoom = Vector2(1,1)
...
func _fixed_process(delta):
    ...
    if Input.is_action_pressed("zoom_1"):
        zoom = Vector2(1, 1)
    if Input.is_action_pressed("zoom_2"):
        zoom = Vector2(1.5, 1.5)
    if Input.is_action_pressed("zoom_3"):
        zoom = Vector2(2, 2)

    get_node("Camera2D").set_zoom(zoom)

I don't understood what's happening.

[guilhermefelipecgs]

I expected the camera stays with the bug.

[guilhermefelipecgs]

Well, bug confirmed for me.

[FEDE0D]

Yeap. I came to the same conclusion. It's on the update_scroll function.
I tried to fix it with no luck.

[guilhermefelipecgs]

_update_scroll and smoothing is not synchronized.

[guilhermefelipecgs]

I know if we remove _update_scroll or do this,

void Camera2D::set_zoom(const Vector2 &p_zoom) {

    zoom = p_zoom;
    Point2 old_smoothed_camera_pos = smoothed_camera_pos;
    _update_scroll();
    smoothed_camera_pos = old_smoothed_camera_pos;
};

it's works, but I dunno if I can do this.

[FEDE0D]

You can try creating a Pull Request and see if they aprove it.
I did something similar with a bug in Parallax Background and I'm still waiting to be merged.

[guilhermefelipecgs]

Do you tested this in your project?
If it's working I'll send a pr.

2015-09-03 18:57 GMT-03:00 Federico notifications@github.com:

You can try creating a Pull Request and see if they aprove it.
I did something similar with a bug in Parallax Background and I'm still
waiting to be merged.

—
Reply to this email directly or view it on GitHub
#2074 (comment).

[FEDE0D]

I can confirm this still happens on the 2.0 alpha build (20151030).

[akien-mga]

Did you try the proposed patch da895e8 by @guilhermefelipecgs?

[FEDE0D]

Yes. Its working right.
@guilhermefelipecgs Can you make a pull request for this file?