Add a multi-screen compositor example

This example shows how shell surfaces can move across outputs in order to
create traditional multi-monitor desktop functionality.

Change-Id: Ie7c0aa1dc47c0c1a944dffcce5237dee92785396
Reviewed-by: Paul Olav Tvete <paul.tvete@qt.io>
Reviewed-by: Pier Luigi Fiorini <pierluigi.fiorini@hawaiios.org>

1 files changed, 77 insertions, 0 deletions

diff --git a/examples/wayland/multi-screen/qml/Chrome.qml b/examples/wayland/multi-screen/qml/Chrome.qml
new file mode 100644
index 000000000..d91a93043
--- /dev/null
+++ b/examples/wayland/multi-screen/qml/Chrome.qml
@@ -0,0 +1,77 @@
+/****************************************************************************
+**
+** Copyright (C) 2016 The Qt Company Ltd.
+** Copyright (C) 2016 Pier Luigi Fiorini <pierluigi.fiorini@gmail.com>
+** Contact: http://www.qt-project.org/legal
+**
+** This file is part of the examples of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:BSD$
+** You may use this file under the terms of the BSD license as follows:
+**
+** "Redistribution and use in source and binary forms, with or without
+** modification, are permitted provided that the following conditions are
+** met:
+**   * Redistributions of source code must retain the above copyright
+**     notice, this list of conditions and the following disclaimer.
+**   * Redistributions in binary form must reproduce the above copyright
+**     notice, this list of conditions and the following disclaimer in
+**     the documentation and/or other materials provided with the
+**     distribution.
+**   * Neither the name of The Qt Company Ltd nor the names of its
+**     contributors may be used to endorse or promote products derived
+**     from this software without specific prior written permission.
+**
+**
+** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+import QtQuick 2.0
+import QtWayland.Compositor 1.0
+
+Item {
+    id: chrome
+    property alias shellSurface: surfaceItem.shellSurface
+    property alias surfaceItem: surfaceItem
+    property alias moveItem: surfaceItem.moveItem
+
+    x: surfaceItem.moveItem.x - surfaceItem.output.geometry.x
+    y: surfaceItem.moveItem.y - surfaceItem.output.geometry.y
+
+    ShellSurfaceItem {
+        id: surfaceItem
+        onSurfaceDestroyed: chrome.destroy();
+    }
+
+    onXChanged: updatePrimary()
+    onYChanged: updatePrimary()
+    function updatePrimary() {
+        var w = surfaceItem.width
+        var h = surfaceItem.height
+        var area = w * h;
+        var screenW = surfaceItem.output.geometry.width;
+        var screenH = surfaceItem.output.geometry.height;
+        var x1 = Math.max(0, x);
+        var y1 = Math.max(0, y);
+        var x2 = Math.min(x + w, screenW);
+        var y2 = Math.min(y + h, screenH);
+        var w1 = Math.max(0, x2 - x1);
+        var h1 = Math.max(0, y2 - y1);
+        if (w1 * h1 * 2 > area) {
+            surfaceItem.setPrimary();
+        }
+    }
+}