1 files changed, 116 insertions, 0 deletions
diff --git a/Studio/Content/Behavior Library/CameraLookAt.qml b/Studio/Content/Behavior Library/CameraLookAt.qml
new file mode 100644
index 0000000..a4d0c9d
--- /dev/null
+++ b/Studio/Content/Behavior Library/CameraLookAt.qml
@@ -0,0 +1,116 @@
+/****************************************************************************
+**
+** Copyright (C) 2017 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of Qt 3D Studio.
+**
+** $QT_BEGIN_LICENSE:BSD$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** BSD License Usage
+** Alternatively, 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."
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+/*[[
+    <Property name="cameraTarget" formalName="Camera Target" type="ObjectRef" default="Scene.Layer.Camera" description="Object in scene the camera should look at" />
+    <Property name="startImmediately" formalName="Start Immediately?" type="Boolean" default="True" publishLevel="Advanced" description="Start immediately, or wait for\nthe Enable action to be called?" />
+
+    <Handler name="start" formalName="Start" category="CameraLookAt" description="Begin looking the target" />
+    <Handler name="stop" formalName="Stop" category="CameraLookAt" description="Stop looking the target" />
+]]*/
+
+import QtStudio3D.Behavior 1.0
+
+Behavior {
+    //External:
+    property string cameraTarget
+    property bool startImmediately
+    //Internal:
+    property bool running: false
+    property var updateFunction
+
+    function start() {
+        running = true;
+    }
+
+    function stop() {
+        running = false;
+    }
+
+    onInitialize: {
+        if (startImmediately)
+            start();
+    }
+
+    onUpdate: {
+        if (!running)
+            return;
+        var targetTransform = calculateGlobalTransform(cameraTarget);
+        var targetSpot = targetTransform.row(3).toVector3d();
+        var cameraTransform = calculateGlobalTransform();
+        var cameraSpot = cameraTransform.row(3).toVector3d();
+
+        var matrix = calculateGlobalTransform("parent").inverted();
+        matrix.m41 = 0;
+        matrix.m42 = 0;
+        matrix.m43 = 0;
+
+        var rotateRay = targetSpot
+                        .minus(cameraSpot)
+                        .times(matrix);
+
+        var rotation = lookAt(rotateRay);
+        setAttributeVector("rotation", rotation);
+    }
+
+    function getAttributeVector(name) {
+        var vec = Qt.vector3d(0, 0, 0);
+        getAttribute(name + ".x", vec.x);
+        getAttribute(name + ".y", vec.y);
+        getAttribute(name + ".z", vec.z);
+        return vec;
+    }
+
+    function setAttributeVector(name, vec) {
+        setAttribute(name + ".x", vec.x);
+        setAttribute(name + ".y", vec.y);
+        setAttribute(name + ".z", vec.z);
+    }
+}