gnome-shell/js/ui/ripples.js
Florian Müllner 8fcd6c7153 cleanup: Use arrow functions for tweener callbacks
While it is legal to use method syntax for the function properties
here, arrow notation is less unexpected and allows us to drop the
separate scope properties.

https://gitlab.gnome.org/GNOME/gnome-shell/merge_requests/608
2019-07-02 12:17:46 +00:00

94 lines
3.8 KiB
JavaScript

// -*- mode: js; js-indent-level: 4; indent-tabs-mode: nil -*-
const { St } = imports.gi;
const Tweener = imports.ui.tweener;
// Shamelessly copied from the layout "hotcorner" ripples implementation
var Ripples = class Ripples {
constructor(px, py, styleClass) {
this._x = 0;
this._y = 0;
this._px = px;
this._py = py;
this._ripple1 = new St.BoxLayout({ style_class: styleClass,
opacity: 0,
can_focus: false,
reactive: false,
visible: false });
this._ripple1.set_pivot_point(px, py);
this._ripple2 = new St.BoxLayout({ style_class: styleClass,
opacity: 0,
can_focus: false,
reactive: false,
visible: false });
this._ripple2.set_pivot_point(px, py);
this._ripple3 = new St.BoxLayout({ style_class: styleClass,
opacity: 0,
can_focus: false,
reactive: false,
visible: false });
this._ripple3.set_pivot_point(px, py);
}
_animRipple(ripple, delay, time, startScale, startOpacity, finalScale) {
// We draw a ripple by using a source image and animating it scaling
// outwards and fading away. We want the ripples to move linearly
// or it looks unrealistic, but if the opacity of the ripple goes
// linearly to zero it fades away too quickly, so we use Tweener's
// 'onUpdate' to give a non-linear curve to the fade-away and make
// it more visible in the middle section.
ripple.x = this._x;
ripple.y = this._y;
ripple._opacity = startOpacity;
ripple.visible = true;
ripple.opacity = 255 * Math.sqrt(startOpacity);
ripple.scale_x = ripple.scale_y = startScale;
ripple.set_translation( - this._px * ripple.width, - this._py * ripple.height, 0.0);
Tweener.addTween(ripple, { _opacity: 0,
scale_x: finalScale,
scale_y: finalScale,
delay: delay,
time: time,
transition: 'linear',
onUpdate: () => ripple.opacity = 255 * Math.sqrt(ripple._opacity),
onComplete: () => ripple.visible = false });
}
addTo(stage) {
if (this._stage !== undefined)
throw new Error('Ripples already added');
this._stage = stage;
this._stage.add_actor(this._ripple1);
this._stage.add_actor(this._ripple2);
this._stage.add_actor(this._ripple3);
}
playAnimation(x, y) {
if (this._stage === undefined)
throw new Error('Ripples not added');
this._x = x;
this._y = y;
this._stage.set_child_above_sibling(this._ripple1, null);
this._stage.set_child_above_sibling(this._ripple2, this._ripple1);
this._stage.set_child_above_sibling(this._ripple3, this._ripple2);
// Show three concentric ripples expanding outwards; the exact
// parameters were found by trial and error, so don't look
// for them to make perfect sense mathematically
// delay time scale opacity => scale
this._animRipple(this._ripple1, 0.0, 0.83, 0.25, 1.0, 1.5);
this._animRipple(this._ripple2, 0.05, 1.0, 0.0, 0.7, 1.25);
this._animRipple(this._ripple3, 0.35, 1.0, 0.0, 0.3, 1);
}
};