gnome-shell/js/ui/main.js
Owen Taylor ff5f960978 Adapt to new Tweener frame ticker API
Now that getTime() has been added to the frame ticker interface
we can implement frame dropping in a more straightforward way
than adjusting the FRAME_RATE member variable to fool Tweener
into doing the right thing.

svn path=/trunk/; revision=156
2009-01-20 18:32:25 +00:00

209 lines
6.5 KiB
JavaScript

/* -*- mode: js2; js2-basic-offset: 4; indent-tabs-mode: nil -*- */
const Clutter = imports.gi.Clutter;
const Shell = imports.gi.Shell;
const Signals = imports.signals;
const Mainloop = imports.mainloop;
const Tweener = imports.tweener.tweener;
const Panel = imports.ui.panel;
const Overlay = imports.ui.overlay;
const RunDialog = imports.ui.runDialog;
const WindowManager = imports.ui.windowManager;
const DEFAULT_BACKGROUND_COLOR = new Clutter.Color();
DEFAULT_BACKGROUND_COLOR.from_pixel(0x2266bbff);
let panel = null;
let overlay = null;
let overlayActive = false;
let runDialog = null;
let wm = null;
// The "FrameTicker" object is an object used to feed new frames to Tweener
// so it can update values and redraw. The default frame ticker for
// Tweener just uses a simple timeout at a fixed frame rate and has no idea
// of "catching up" by dropping frames.
//
// We substitute it with custom frame ticker here that connects Tweener to
// a Clutter.TimeLine. Now, Clutter.Timeline itself isn't a whole lot more
// sophisticated than a simple timeout at a fixed frame rate, but at least
// it knows how to drop frames. (See HippoAnimationManager for a more
// sophisticated view of continous time updates; even better is to pay
// attention to the vertical vblank and sync to that when possible.)
//
function ClutterFrameTicker() {
this._init();
}
ClutterFrameTicker.prototype = {
FRAME_RATE : 60,
_init : function() {
// We don't have a finite duration; tweener will tell us to stop
// when we need to stop, so use 1000 seconds as "infinity"
this._timeline = new Clutter.Timeline({ fps: this.FRAME_RATE,
duration: 1000*1000 });
this._currentTime = 0;
this._frame = 0;
let me = this;
this._timeline.connect('new-frame',
function(timeline, frame) {
me._onNewFrame(frame);
});
},
_onNewFrame : function(frame) {
// Unfortunately the interface to to send a new frame to tweener
// is a simple "next frame" and there is no provision for signaling
// that frames have been skipped or just telling it the new time.
// But what it actually does internally is just:
//
// _currentTime += 1000/_ticker.FRAME_RATE;
//
// So by dynamically adjusting the value of FRAME_RATE we can trick
// it into dealing with dropped frames.
// If there is a lot of setup to start the animation, then
// first frame number we get from clutter might be a long ways
// into the animation (or the animation might even be done).
// That looks bad, so we always start one frame into the
// animation then only do frame dropping from there.
let delta;
if (this._frame == 0)
delta = 1;
else
delta = frame - this._frame;
if (delta == 0) // protect against divide-by-0 if we get a frame twice
delta = 1;
// currentTime is in milliseconds
this._currentTime += (1000 * delta) / this.FRAME_RATE;
this._frame = frame;
this.emit('prepare-frame');
},
getTime : function() {
return this._currentTime;
},
start : function() {
this._timeline.start();
},
stop : function() {
this._timeline.stop();
this._frame = 0;
this._currentTime = 0;
}
};
Signals.addSignalMethods(ClutterFrameTicker.prototype);
function start() {
let global = Shell.Global.get();
global.grab_dbus_service();
global.start_task_panel();
Tweener.setFrameTicker(new ClutterFrameTicker());
// The background color really only matters if there is no desktop
// window (say, nautilus) running. We set it mostly so things look good
// when we are running inside Xephyr.
global.stage.color = DEFAULT_BACKGROUND_COLOR;
// Mutter currently hardcodes putting "Yessir. The compositor is running""
// in the overlay. Clear that out.
let children = global.overlay_group.get_children();
for (let i = 0; i < children.length; i++)
children[i].destroy();
// metacity-clutter currently uses the same prefs as plain metacity,
// which probably means we'll be starting out with multiple workspaces;
// remove any unused ones
let windows = global.get_windows();
let maxWorkspace = 0;
for (let i = 0; i < windows.length; i++) {
let win = windows[i];
if (!win.get_meta_window().is_on_all_workspaces() &&
win.get_workspace() > maxWorkspace) {
maxWorkspace = win.get_workspace();
}
}
let screen = global.screen;
if (screen.n_workspaces > maxWorkspace) {
for (let w = screen.n_workspaces - 1; w > maxWorkspace; w--) {
let workspace = screen.get_workspace_by_index(w);
screen.remove_workspace(workspace, 0);
}
}
global.connect('panel-run-dialog', function(panel) {
// Make sure not more than one run dialog is shown.
if (!runDialog) {
runDialog = new RunDialog.RunDialog();
let end_handler = function() {
runDialog.destroy();
runDialog = null;
};
runDialog.connect('run', end_handler);
runDialog.connect('cancel', end_handler);
if (!runDialog.show())
end_handler();
}
});
panel = new Panel.Panel();
global.set_stage_input_area(0, 0, global.screen_width, Panel.PANEL_HEIGHT);
overlay = new Overlay.Overlay();
wm = new WindowManager.WindowManager();
let display = global.screen.get_display();
display.connect('overlay-key', function(display) {
if (overlay.visible) {
hide_overlay();
} else {
show_overlay();
}
});
}
// Used to go into a mode where all keyboard and mouse input goes to
// the stage. Returns true if we successfully grabbed the keyboard and
// went modal, false otherwise
function startModal() {
let global = Shell.Global.get();
if (!global.grab_keyboard())
return false;
global.set_stage_input_area(0, 0, global.screen_width, global.screen_height);
return true;
}
function endModal() {
let global = Shell.Global.get();
global.ungrab_keyboard();
global.set_stage_input_area(0, 0, global.screen_width, Panel.PANEL_HEIGHT);
}
function show_overlay() {
if (startModal()) {
overlayActive = true;
overlay.show();
}
}
function hide_overlay() {
overlay.hide();
overlayActive = false;
endModal();
}