QmlDesigner: Implement better camera navigation in 3D edit view

Edit camera is now controlled as in Qt 3D Studio:
ALT + left button orbits camera.
ALT + middle button pans camera.
ALT + right button zooms camera.
Wheel zooms camera.

Task-number: QDS-1206
Change-Id: Ia72644073d172b00483ceed8bcc5ffb8dce68741
Reviewed-by: Thomas Hartmann <thomas.hartmann@qt.io>

1 files changed, 132 insertions, 0 deletions

diff --git a/share/qtcreator/qml/qmlpuppet/qml2puppet/editor3d/generalhelper.cpp b/share/qtcreator/qml/qmlpuppet/qml2puppet/editor3d/generalhelper.cpp
new file mode 100644
index 00000000000..b4872ed48fb
--- /dev/null
+++ b/share/qtcreator/qml/qmlpuppet/qml2puppet/editor3d/generalhelper.cpp
@@ -0,0 +1,132 @@
+/****************************************************************************
+**
+** Copyright (C) 2019 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of Qt Creator.
+**
+** 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.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 3 as published by the Free Software
+** Foundation with exceptions as appearing in the file LICENSE.GPL3-EXCEPT
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-3.0.html.
+**
+****************************************************************************/
+#include "generalhelper.h"
+
+#ifdef QUICK3D_MODULE
+
+#include <QtQuick3D/private/qquick3dorthographiccamera_p.h>
+#include <QtQuick3D/private/qquick3dperspectivecamera_p.h>
+#include <QtCore/qhash.h>
+#include <QtGui/qmatrix4x4.h>
+
+namespace QmlDesigner {
+namespace Internal {
+
+GeneralHelper::GeneralHelper()
+    : QObject()
+{
+    m_overlayUpdateTimer.setInterval(16);
+    m_overlayUpdateTimer.setSingleShot(true);
+    QObject::connect(&m_overlayUpdateTimer, &QTimer::timeout,
+                     this, &GeneralHelper::overlayUpdateNeeded);
+}
+
+void GeneralHelper::requestOverlayUpdate()
+{
+    if (!m_overlayUpdateTimer.isActive())
+        m_overlayUpdateTimer.start();
+}
+
+QString GeneralHelper::generateUniqueName(const QString &nameRoot)
+{
+    static QHash<QString, int> counters;
+    int count = counters[nameRoot]++;
+    return QStringLiteral("%1_%2").arg(nameRoot).arg(count);
+}
+
+void GeneralHelper::orbitCamera(QQuick3DCamera *camera, const QVector3D &startRotation,
+                                const QVector3D &lookAtPoint, const QVector3D &pressPos,
+                                const QVector3D &currentPos)
+{
+    QVector3D dragVector = currentPos - pressPos;
+
+    if (dragVector.length() < 0.001f)
+        return;
+
+    camera->setRotation(startRotation);
+    QVector3D newRotation(dragVector.y(), dragVector.x(), 0.f);
+    newRotation *= 0.5f; // Emprically determined multiplier for nice drag
+    newRotation += startRotation;
+
+    camera->setRotation(newRotation);
+
+    const QVector3D oldLookVector = camera->position() - lookAtPoint;
+    QMatrix4x4 m = camera->sceneTransform();
+    const float *dataPtr(m.data());
+    QVector3D newLookVector(-dataPtr[8], -dataPtr[9], -dataPtr[10]);
+    newLookVector.normalize();
+    newLookVector *= oldLookVector.length();
+
+    camera->setPosition(lookAtPoint + newLookVector);
+}
+
+// Pans camera and returns the new look-at point
+QVector3D GeneralHelper::panCamera(QQuick3DCamera *camera, const QMatrix4x4 startTransform,
+                                   const QVector3D &startPosition, const QVector3D &startLookAt,
+                                   const QVector3D &pressPos, const QVector3D &currentPos,
+                                   float zoomFactor)
+{
+    QVector3D dragVector = currentPos - pressPos;
+
+    if (dragVector.length() < 0.001f)
+        return startLookAt;
+
+    const float *dataPtr(startTransform.data());
+    const QVector3D xAxis = QVector3D(dataPtr[0], dataPtr[1], dataPtr[2]).normalized();
+    const QVector3D yAxis = QVector3D(dataPtr[4], dataPtr[5], dataPtr[6]).normalized();
+    const QVector3D xDelta = -1.f * xAxis * dragVector.x();
+    const QVector3D yDelta = yAxis * dragVector.y();
+    const QVector3D delta = (xDelta + yDelta) * zoomFactor;
+
+    camera->setPosition(startPosition + delta);
+    return startLookAt + delta;
+}
+
+float GeneralHelper::zoomCamera(QQuick3DCamera *camera, float distance, float defaultLookAtDistance,
+                                const QVector3D &lookAt, float zoomFactor, bool relative)
+{
+    // Emprically determined divisor for nice zoom
+    float multiplier = 1.f + (distance / 40.f);
+    float newZoomFactor = relative ? qBound(.0001f, zoomFactor * multiplier, 10000.f)
+                                   : zoomFactor;
+
+    if (qobject_cast<QQuick3DOrthographicCamera *>(camera)) {
+        // Ortho camera we can simply scale
+        camera->setScale(QVector3D(newZoomFactor, newZoomFactor, newZoomFactor));
+    } else if (qobject_cast<QQuick3DPerspectiveCamera *>(camera)) {
+        // Perspective camera is zoomed by moving camera forward or backward while keeping the
+        // look-at point the same
+        const QVector3D lookAtVec = (camera->position() - lookAt).normalized();
+        const float newDistance = defaultLookAtDistance * newZoomFactor;
+        camera->setPosition(lookAt + (lookAtVec * newDistance));
+    }
+
+    return newZoomFactor;
+}
+
+}
+}
+
+#endif // QUICK3D_MODULE