Make dragged objects follow the cursor accurately

Fixes issues when dragging objects by directly grabbing the object
instead of using a widget:

- Objects now accurately track the cursor
- Cursor offset to object position is calculated so there is no
  initial jump when drag starts
- Axis locked dragging (shift) is supported

Task-number: QT3DS-2901
Change-Id: I5b16de517d33509b9789c0ad538d9af63dba2502
Reviewed-by: Jere Tuliniemi <jere.tuliniemi@qt.io>
Reviewed-by: Antti Määttä <antti.maatta@qt.io>
Reviewed-by: Mahmoud Badri <mahmoud.badri@qt.io>
Reviewed-by: Miikka Heikkinen <miikka.heikkinen@qt.io>

1 files changed, 4 insertions, 2 deletions

diff --git a/src/Authoring/Studio/Render/Q3DSTranslation.h b/src/Authoring/Studio/Render/Q3DSTranslation.h
index e682d1cb..a6ea0491 100644
--- a/src/Authoring/Studio/Render/Q3DSTranslation.h
+++ b/src/Authoring/Studio/Render/Q3DSTranslation.h
@@ -183,6 +183,8 @@ private:
     bool m_editCameraEnabled = false;
     Q3DSGraphObjectTranslator *m_dragTranslator = nullptr;
     Q3DSCameraNode *m_dragCamera = nullptr;
+    QPoint m_dragStartMousePos;
+    QPoint m_dragPosDiff;
     bool m_presentationInit = false;
 
     Q3DSLayerNode *m_backgroundLayer = nullptr;
@@ -259,8 +261,8 @@ public:
                                                      Q3DSGraphObjectTranslator *aliasTranslator
                                                         = nullptr);
 
-    void prepareDrag(Q3DSGraphObjectTranslator *selected = nullptr);
-    void prepareWidgetDrag(Q3DSGraphObject *obj);
+    void prepareDrag(const QPoint &mousePos, Q3DSGraphObjectTranslator *selected = nullptr);
+    void prepareWidgetDrag(const QPoint &mousePos, Q3DSGraphObject *obj);
     void endDrag(bool dragReset, CUpdateableDocumentEditor &inEditor);
     void endPickWidget();