Use separate MouseArea3D to calculate drag vector

Using the MouseArea3D linked to gizmo to manage the drag leads to
slight unwanted drift on the drag plane, as it moves with the gizmo.
Fixed by using a helper MouseArea3D to calculate drag vector.
Helper area's transform is set at mouse press time and is not changed
during the drag.

Change-Id: I50d3f738277bd34005c977423d114abc8dbed520
Fixes: QDS-1312
Reviewed-by: Mahmoud Badri <mahmoud.badri@qt.io>
Reviewed-by: Thomas Hartmann <thomas.hartmann@qt.io>

1 files changed, 30 insertions, 6 deletions

diff --git a/share/qtcreator/qml/qmlpuppet/qml2puppet/editor3d/mousearea3d.cpp b/share/qtcreator/qml/qmlpuppet/qml2puppet/editor3d/mousearea3d.cpp
index 71a67a9577..4c85557634 100644
--- a/share/qtcreator/qml/qmlpuppet/qml2puppet/editor3d/mousearea3d.cpp
+++ b/share/qtcreator/qml/qmlpuppet/qml2puppet/editor3d/mousearea3d.cpp
@@ -83,6 +83,11 @@ QQuick3DNode *MouseArea3D::pickNode() const
     return m_pickNode;
 }
 
+MouseArea3D *MouseArea3D::dragHelper() const
+{
+    return m_dragHelper;
+}
+
 qreal MouseArea3D::x() const
 {
     return m_x;
@@ -179,6 +184,15 @@ void MouseArea3D::setPickNode(QQuick3DNode *node)
     emit pickNodeChanged();
 }
 
+void MouseArea3D::setDragHelper(MouseArea3D *dragHelper)
+{
+    if (m_dragHelper == dragHelper)
+        return;
+
+    m_dragHelper = dragHelper;
+    emit dragHelperChanged();
+}
+
 void MouseArea3D::setX(qreal x)
 {
     if (qFuzzyCompare(m_x, x))
@@ -433,19 +447,22 @@ void MouseArea3D::applyFreeRotation(QQuick3DNode *node, const QVector3D &startRo
     node->rotate(degrees, finalAxis, QQuick3DNode::SceneSpace);
 }
 
-QVector3D MouseArea3D::getMousePosInPlane(const QPointF &mousePosInView) const
+QVector3D MouseArea3D::getMousePosInPlane(const MouseArea3D *helper,
+                                          const QPointF &mousePosInView) const
 {
+    if (!helper)
+        helper = this;
     const QVector3D mousePos1(float(mousePosInView.x()), float(mousePosInView.y()), 0);
     const QVector3D mousePos2(float(mousePosInView.x()), float(mousePosInView.y()), 1);
     const QVector3D rayPos0 = m_view3D->mapTo3DScene(mousePos1);
     const QVector3D rayPos1 = m_view3D->mapTo3DScene(mousePos2);
-    const QVector3D globalPlanePosition = mapPositionToScene(QVector3D(0, 0, 0));
+    const QVector3D globalPlanePosition = helper->mapPositionToScene(QVector3D(0, 0, 0));
     const QVector3D intersectGlobalPos = rayIntersectsPlane(rayPos0, rayPos1,
                                                             globalPlanePosition, forward());
     if (qFuzzyCompare(intersectGlobalPos.z(), -1))
         return intersectGlobalPos;
 
-    return mapPositionFromScene(intersectGlobalPos);
+    return helper->mapPositionFromScene(intersectGlobalPos);
 }
 
 bool MouseArea3D::eventFilter(QObject *, QEvent *event)
@@ -505,7 +522,13 @@ bool MouseArea3D::eventFilter(QObject *, QEvent *event)
     case QEvent::MouseButtonPress: {
         auto const mouseEvent = static_cast<QMouseEvent *>(event);
         if (mouseEvent->button() == Qt::LeftButton) {
-            m_mousePosInPlane = getMousePosInPlane(mouseEvent->pos());
+            // Reset drag helper area to global transform of this area
+            if (m_dragHelper) {
+                m_dragHelper->setPosition(scenePosition());
+                m_dragHelper->setRotation(sceneRotation());
+                m_dragHelper->setScale(sceneScale());
+            }
+            m_mousePosInPlane = getMousePosInPlane(m_dragHelper, mouseEvent->pos());
             if (mouseOnTopOfMouseArea(m_mousePosInPlane, mouseEvent->pos())) {
                 setDragging(true);
                 emit pressed(m_mousePosInPlane, mouseEvent->pos(), pickAngle);
@@ -527,7 +550,7 @@ bool MouseArea3D::eventFilter(QObject *, QEvent *event)
         auto const mouseEvent = static_cast<QMouseEvent *>(event);
         if (mouseEvent->button() == Qt::LeftButton) {
             if (m_dragging) {
-                QVector3D mousePosInPlane = getMousePosInPlane(mouseEvent->pos());
+                QVector3D mousePosInPlane = getMousePosInPlane(m_dragHelper, mouseEvent->pos());
                 if (qFuzzyCompare(mousePosInPlane.z(), -1))
                     mousePosInPlane = m_mousePosInPlane;
                 setDragging(false);
@@ -554,7 +577,8 @@ bool MouseArea3D::eventFilter(QObject *, QEvent *event)
     case QEvent::MouseMove:
     case QEvent::HoverMove: {
         auto const mouseEvent = static_cast<QMouseEvent *>(event);
-        const QVector3D mousePosInPlane = getMousePosInPlane(mouseEvent->pos());
+        const QVector3D mousePosInPlane = getMousePosInPlane(m_dragging ? m_dragHelper : this,
+                                                             mouseEvent->pos());
         const bool hasMouse = mouseOnTopOfMouseArea(mousePosInPlane, mouseEvent->pos());
 
         setHovering(hasMouse);