From 6509cc72e730e69278068d13078606828eade62a Mon Sep 17 00:00:00 2001
From: wmayer <wmayer@users.sourceforge.net>
Date: Sat, 8 Apr 2023 12:37:15 +0200
Subject: [PATCH] Gui: add method to convert between QPoint and SbVec2s
 considering device pixel ratio

---
 src/Gui/View3DInventorViewer.cpp | 28 ++++++++++++++++++++++++++++
 src/Gui/View3DInventorViewer.h   | 21 +++++++++++++++++++++
 src/Gui/View3DPy.cpp             |  6 ++++--
 3 files changed, 53 insertions(+), 2 deletions(-)

diff --git a/src/Gui/View3DInventorViewer.cpp b/src/Gui/View3DInventorViewer.cpp
index 82f915810e..441136456f 100644
--- a/src/Gui/View3DInventorViewer.cpp
+++ b/src/Gui/View3DInventorViewer.cpp
@@ -2424,6 +2424,34 @@ SbVec2s View3DInventorViewer::getPointOnScreen(const SbVec3f& pnt) const
     return SbVec2s(x, y);
 }
 
+QPoint View3DInventorViewer::toQPoint(const SbVec2s& pnt) const
+{
+    const SbViewportRegion& vp = this->getSoRenderManager()->getViewportRegion();
+    const SbVec2s& vps = vp.getViewportSizePixels();
+    int xpos = pnt[0];
+    int ypos = vps[1] - pnt[0] - 1;
+
+    qreal dev_pix_ratio = devicePixelRatio();
+    xpos = int(std::roundf(xpos / dev_pix_ratio));
+    ypos = int(std::roundf(ypos / dev_pix_ratio));
+
+    return QPoint(xpos, ypos);
+}
+
+SbVec2s View3DInventorViewer::fromQPoint(const QPoint& pnt) const
+{
+    const SbViewportRegion& vp = this->getSoRenderManager()->getViewportRegion();
+    const SbVec2s& vps = vp.getViewportSizePixels();
+    int xpos = pnt.x();
+    int ypos = pnt.y();
+
+    qreal dev_pix_ratio = devicePixelRatio();
+    xpos = int(std::roundf(xpos * dev_pix_ratio));
+    ypos = int(std::roundf(ypos * dev_pix_ratio));
+
+    return SbVec2s(short(xpos), vps[1] - short(ypos) - 1);
+}
+
 void View3DInventorViewer::getNearPlane(SbVec3f& rcPt, SbVec3f& rcNormal) const
 {
     SoCamera* pCam = getSoRenderManager()->getCamera();
diff --git a/src/Gui/View3DInventorViewer.h b/src/Gui/View3DInventorViewer.h
index c7331bf279..4db02acc94 100644
--- a/src/Gui/View3DInventorViewer.h
+++ b/src/Gui/View3DInventorViewer.h
@@ -305,27 +305,48 @@ public:
     void    setViewDirection(SbVec3f);
     /** Returns the up direction */
     SbVec3f getUpDirection() const;
+
     /** Returns the orientation of the camera. */
     SbRotation getCameraOrientation() const;
+
     /** Returns the 3d point on the focal plane to the given 2d point. */
     SbVec3f getPointOnFocalPlane(const SbVec2s&) const;
+
     /** Returns the 2d coordinates on the screen to the given 3d point. */
     SbVec2s getPointOnScreen(const SbVec3f&) const;
+
+    /** Converts Inventor coordinates into Qt coordinates.
+     * The conversion takes the device pixel ratio into account.
+     */
+    QPoint toQPoint(const SbVec2s&) const;
+
+    /** Converts Qt coordinates into Inventor coordinates.
+     * The conversion takes the device pixel ratio into account.
+     */
+    SbVec2s fromQPoint(const QPoint&) const;
+
     /** Returns the near plane represented by its normal and base point. */
     void getNearPlane(SbVec3f& rcPt, SbVec3f& rcNormal) const;
+
     /** Returns the far plane represented by its normal and base point. */
     void getFarPlane(SbVec3f& rcPt, SbVec3f& rcNormal) const;
+
     /** Adds or remove a manipulator to/from the scenegraph. */
     void toggleClippingPlane(int toggle=-1, bool beforeEditing=false,
             bool noManip=false, const Base::Placement &pla = Base::Placement());
+
     /** Checks whether a clipping plane is set or not. */
     bool hasClippingPlane() const;
+
     /** Project the given normalized 2d point onto the near plane */
     SbVec3f projectOnNearPlane(const SbVec2f&) const;
+
     /** Project the given normalized 2d point onto the far plane */
     SbVec3f projectOnFarPlane(const SbVec2f&) const;
+
     /** Project the given 2d point to a line */
     void projectPointToLine(const SbVec2s&, SbVec3f& pt1, SbVec3f& pt2) const;
+
     /** Get the normalized position of the 2d point. */
     SbVec2f getNormalizedPosition(const SbVec2s&) const;
     //@}
diff --git a/src/Gui/View3DPy.cpp b/src/Gui/View3DPy.cpp
index 2f5608be3e..beb194ccfe 100644
--- a/src/Gui/View3DPy.cpp
+++ b/src/Gui/View3DPy.cpp
@@ -1312,9 +1312,11 @@ Py::Object View3DInventorPy::getCursorPos(const Py::Tuple& args)
         throw Py::Exception();
     try {
         QPoint pos = getView3DIventorPtr()->mapFromGlobal(QCursor::pos());
+        auto viewer = getView3DIventorPtr()->getViewer();
+        SbVec2s vec = viewer->fromQPoint(pos);
         Py::Tuple tuple(2);
-        tuple.setItem(0, Py::Int(pos.x()));
-        tuple.setItem(1, Py::Int(getView3DIventorPtr()->height()-pos.y()-1));
+        tuple.setItem(0, Py::Int(vec[0]));
+        tuple.setItem(1, Py::Int(vec[1]));
         return tuple;
     }
     catch (const Py::Exception&) {