gnome-shell/js/ui/overlay.js

/* -*- mode: js2; js2-basic-offset: 4; tab-width: 4; indent-tabs-mode: nil -*- */

const Signals = imports.signals;
const Mainloop = imports.mainloop;
const Tweener = imports.tweener.tweener;
const Clutter = imports.gi.Clutter;
const Gio = imports.gi.Gio;
const Gtk = imports.gi.Gtk;

const Main = imports.ui.main;
const Panel = imports.ui.panel;
const Meta = imports.gi.Meta;
const Shell = imports.gi.Shell;
const AppDisplay = imports.ui.appdisplay;

const OVERLAY_BACKGROUND_COLOR = new Clutter.Color();
OVERLAY_BACKGROUND_COLOR.from_pixel(0x000000ff);

const SIDESHOW_PAD = 6;
const SIDESHOW_MIN_WIDTH = 250;
const SIDESHOW_SEARCH_BG_COLOR = new Clutter.Color();
SIDESHOW_SEARCH_BG_COLOR.from_pixel(0xffffffff);
const SIDESHOW_TEXT_COLOR = new Clutter.Color();
SIDESHOW_TEXT_COLOR.from_pixel(0xffffffff);

//Time for initial animation going into overlay mode
const ANIMATION_TIME = 0.5;

//How much to scale the desktop down by in overlay mode
const DESKTOP_SCALE = 0.75;

//Windows are slightly translucent in the overlay mode
const WINDOW_OPACITY = 0.9 * 255;

//Define a layout scheme for small window counts. For larger
//counts we fall back to an algorithm. We need more schemes here
//unless we have a really good algorithm.

//Each triplet is [xCenter, yCenter, scale] where the scale
//is relative to the width of the desktop.
const POSITIONS = {
        1: [[0.5, 0.5, 0.8]],
        2: [[0.25, 0.5, 0.4], [0.75, 0.5, 0.4]],
        3: [[0.25, 0.25, 0.33],  [0.75, 0.25, 0.33],  [0.5, 0.75, 0.33]],
        4: [[0.25, 0.25, 0.33],   [0.75, 0.25, 0.33], [0.75, 0.75, 0.33], [0.25, 0.75, 0.33]],
        5: [[0.165, 0.25, 0.28], [0.495, 0.25, 0.28], [0.825, 0.25, 0.28], [0.25, 0.75, 0.4], [0.75, 0.75, 0.4]]
};

function Sideshow(width) {
    this._init(width);
}

Sideshow.prototype = {
_init : function(width) {
    let me = this;

    let global = Shell.Global.get();
    this._group = new Clutter.Group();
    this._group.hide();
    global.stage.add_actor(this._group);
    let icontheme = Gtk.IconTheme.get_default();
    let rect = new Clutter.Rectangle({ color: SIDESHOW_SEARCH_BG_COLOR,
        x: SIDESHOW_PAD,
        y: Panel.PANEL_HEIGHT + SIDESHOW_PAD,
        width: width,
        height: 24});
    this._group.add_actor(rect);

    let searchIconTexture = new Clutter.Texture({ x: SIDESHOW_PAD + 2,
        y: rect.y + 2 });
    let searchIconPath = icontheme.lookup_icon('gtk-find', 16, 0).get_filename();
    searchIconTexture.set_from_file(searchIconPath);
    this._group.add_actor(searchIconTexture);

    this._searchEntry = new Clutter.Entry({
        font_name: "Sans 14px",
        x: searchIconTexture.x
        + searchIconTexture.width + 4,
        y: searchIconTexture.y,
        width: rect.width - (searchIconTexture.x),
        height: searchIconTexture.height});
    this._group.add_actor(this._searchEntry);
    global.stage.set_key_focus(this._searchEntry);
    this._searchQueued = false;
    this._searchActive = false;
    this._searchEntry.connect('notify::text', function (se, prop) {           
        if (me._searchQueued)
            return;
        Mainloop.timeout_add(250, function() {
            let text = me._searchEntry.text;            
            me._searchQueued = false;
            me._searchActive = text != '';              
            me._appdisplay.setSearch(text);
            return false;
        });
    });
    this._searchEntry.connect('activate', function (se) {
        if (!me._searchActive)
            return false;
        me._appdisplay.searchActivate();
        return true;
    });
    this._searchEntry.connect('key-press-event', function (se, e) {
        let code = e.get_code();
        log("code: " + code);
        if (code == 111) {
            me._appdisplay.selectUp();
            return true;
        } else if (code == 116) {
            me._appdisplay.selectDown();
            return true;
        }
        return false;
    });

    let appsText = new Clutter.Label({ color: SIDESHOW_TEXT_COLOR,
        font_name: "Sans Bold 14px",
        text: "Applications",
        x: SIDESHOW_PAD,
        y: this._searchEntry.y + this._searchEntry.height + 10,
        height: 16});
    this._group.add_actor(appsText);

    let menuY = appsText.y + appsText.height + 6;
    this._appdisplay = new AppDisplay.AppDisplay(SIDESHOW_PAD,
            menuY, width, global.screen_height - menuY);

    /* Proxy the activated signal */
    this._appdisplay.connect('activated', function(appdisplay) {
        me.emit('activated');
    });
},

show: function() {
    this._group.show();
    this._appdisplay.show();
},

hide: function() {
    this._group.hide();
    this._appdisplay.hide();
}
};
Signals.addSignalMethods(Sideshow.prototype);

function Overlay() {
    this._init();
}

Overlay.prototype = {
_init : function() {
    let me = this;

    let global = Shell.Global.get();

    this._group = new Clutter.Group();
    this.visible = false;

    let background = new Clutter.Rectangle({ color: OVERLAY_BACKGROUND_COLOR,
        reactive: true,
        x: 0,
        y: Panel.PANEL_HEIGHT,
        width: global.screen_width,
        height: global.screen_width - Panel.PANEL_HEIGHT });
    this._group.add_actor(background);

    this._group.hide();
    global.overlay_group.add_actor(this._group);

    this._windowClones = [];

    // TODO - recalculate everything when desktop size changes
    this._recalculateSize();

    this._sideshow = new Sideshow(this._desktopX - 10);
    this._sideshow.connect('activated', function(sideshow) {
        // TODO - have some sort of animation/effect while
        // transitioning to the new app.  We definitely need
        // startup-notification integration at least.
        me._deactivate();
    });
},

_recalculateSize: function () {
    let global = Shell.Global.get();
    let screenWidth = global.screen_width;
    let screenHeight = global.screen_height;
    // The desktop windows are shown on top of a scaled down version of the
    // desktop. This is positioned at the right side of the screen
    this._desktopWidth = screenWidth * DESKTOP_SCALE;
    this._desktopHeight = screenHeight * DESKTOP_SCALE;
    this._desktopX = screenWidth - this._desktopWidth - 10;
    this._desktopY = Panel.PANEL_HEIGHT + (screenHeight - this._desktopHeight - Panel.PANEL_HEIGHT) / 2;
},

show : function() {
    if (this.visible)
        return;
    this.visible = true;

    let global = Shell.Global.get();

    let windows = global.get_windows();
    let desktopWindow = null;

    this._recalculateSize();

    for (let i = 0; i < windows.length; i++)
        if (windows[i].get_window_type() == Meta.WindowType.DESKTOP)
            desktopWindow = windows[i];

    // If a file manager is displaying desktop icons, there will be a desktop window.
    // This window will have the size of the whole desktop. When such window is not present
    // (e.g. when the preference for showing icons on the desktop is disabled by the user
    // or we are running inside a Xephyr window), we should create a desktop rectangle
    // to serve as the background.
    if (desktopWindow)
        this._createDesktopClone(desktopWindow);
    else
        this._createDesktopRectangle();

    // Count the total number of windows so we know what layout scheme to use
    let numberOfWindows = 0;
    for (let i = 0; i < windows.length; i++) {
        let w = windows[i];
        if (w == desktopWindow || w.is_override_redirect())
            continue;

        numberOfWindows++;
    }

    // Now create actors for all the desktop windows. Do it in
    // reverse order so that the active actor ends up on top
    let windowIndex = 0;
    for (let i = windows.length - 1; i >= 0; i--) {
        let w = windows[i];
        if (w == desktopWindow || w.is_override_redirect())
            continue;
        this._createWindowClone(w, numberOfWindows - windowIndex - 1, numberOfWindows);

        windowIndex++;
    }

    this._sideshow.show();

    // All the the actors in the window group are completely obscured,
    // hiding the group holding them while the overlay is displayed greatly
    // increases performance of the overlay especially when there are many
    // windows visible.
    //
    // If we switched to displaying the actors in the overlay rather than
    // clones of them, this would obviously no longer be necessary.
    global.window_group.hide()
    this._group.show();
},

hide : function() {
    if (!this.visible)
        return;
    let global = Shell.Global.get();

    this.visible = false;
    global.window_group.show()
    this._group.hide();

    for (let i = 0; i < this._windowClones.length; i++) {
        this._windowClones[i].destroy();
    }

    this._sideshow.hide();

    this._windowClones = [];
},

_createDesktopClone : function(w) {
    let clone = new Clutter.CloneTexture({ parent_texture: w.get_texture(),
        reactive: true,
        x: 0,
        y: 0 });
    this._addDesktop(clone);
},

_createDesktopRectangle : function() {
    let global = Shell.Global.get();
    // In the case when we have a desktop window from the file manager, its height is
    // full-screen, i.e. it includes the height of the panel, so we should not subtract
    // the height of the panel from global.screen_height here either to have them show
    // up identically.
    // We are also using (0,0) coordinates in both cases which makes the background
    // window animate out from behind the panel.
    let desktopRectangle = new Clutter.Rectangle({ color: global.stage.color,
        reactive: true,
        x: 0,
        y: 0,
        width: global.screen_width,
        height: global.screen_height });
    this._addDesktop(desktopRectangle);
},

_addDesktop : function(desktop) {
    let me = this;

    this._windowClones.push(desktop);
    this._group.add_actor(desktop);

    // Since the right side only moves a little bit (the width of padding
    // we add) it looks less jittery to put the anchor there.
    desktop.move_anchor_point_from_gravity(Clutter.Gravity.NORTH_EAST);
    Tweener.addTween(desktop,
            { x: this._desktopX + this._desktopWidth,
        y: this._desktopY,
        scale_x: DESKTOP_SCALE,
        scale_y: DESKTOP_SCALE,
        time: ANIMATION_TIME,
        transition: "easeOutQuad"
            });

    desktop.connect("button-press-event",
            function() {
        me._deactivate();
    });
},

//windowIndex == 0 => top in stacking order
_computeWindowPosition : function(windowIndex, numberOfWindows) {
    if (numberOfWindows in POSITIONS)
        return POSITIONS[numberOfWindows][windowIndex];

    // If we don't have a predefined scheme for this window count, overlap the windows
    // along the diagonal of the desktop (improve this!)
    let fraction = Math.sqrt(1/numberOfWindows);

    // The top window goes at the lower right - this is different from the
    // fixed position schemes where the windows are in "reading order"
    // and the top window goes at the upper left.
    let pos = (numberOfWindows - windowIndex - 1) / (numberOfWindows - 1);
    let xCenter = (fraction / 2) + (1 - fraction) * pos;
    let yCenter = xCenter;

    return [xCenter, yCenter, fraction];
},

_createWindowClone : function(w, windowIndex, numberOfWindows) {
    let me = this;

    // We show the window using "clones" of the texture .. separate
    // actors that mirror the original actors for the window. For
    // animation purposes, it may be better to actually move the
    // original actors about instead.

    let clone = new Clutter.CloneTexture({ parent_texture: w.get_texture(),
        reactive: true,
        x: w.x,
        y: w.y });

    let [xCenter, yCenter, fraction] = this._computeWindowPosition(windowIndex, numberOfWindows);

    let desiredSize = this._desktopWidth * fraction;

    xCenter = this._desktopX + xCenter * this._desktopWidth;
    yCenter = this._desktopY + yCenter * this._desktopHeight;

    let size = clone.width;
    if (clone.height > size)
        size = clone.height;

    // Never scale up
    let scale = desiredSize / size;
    if (scale > 1)
        scale = 1;

    this._group.add_actor(clone);
    this._windowClones.push(clone);

    Tweener.addTween(clone,
            { x: xCenter - 0.5 * scale * w.width,
        y: yCenter - 0.5 * scale * w.height,
        scale_x: scale,
        scale_y: scale,
        time: ANIMATION_TIME,
        opacity: WINDOW_OPACITY,
        transition: "easeOutQuad"
            });

    clone.connect("button-press-event",
            function(clone, event) {
        me._activateWindow(w, event.get_time());
    });
},

_activateWindow : function(w, time) {
    this._deactivate();
    w.get_meta_window().activate(time);
},

_deactivate : function() {
    Main.hide_overlay();
}
};