From 4af6c5a13eb3f00a223abd672c33b2a1ee514fb7 Mon Sep 17 00:00:00 2001
From: wmayer <wmayer@users.sourceforge.net>
Date: Tue, 19 Jan 2021 19:19:30 +0100
Subject: [PATCH] Gui: [skip ci] update standard cursors of 3d view when device
 pixel ratio changes (e.g. by moving between standard and high DPI monitor)

---
 src/Gui/View3DInventorViewer.cpp | 57 ++++++++++++++++++--------------
 src/Gui/View3DInventorViewer.h   |  1 +
 2 files changed, 34 insertions(+), 24 deletions(-)

diff --git a/src/Gui/View3DInventorViewer.cpp b/src/Gui/View3DInventorViewer.cpp
index 9c6de05ef1..5e4262e757 100644
--- a/src/Gui/View3DInventorViewer.cpp
+++ b/src/Gui/View3DInventorViewer.cpp
@@ -600,32 +600,12 @@ void View3DInventorViewer::init()
     }
 
     //create the cursors
-#if defined(Q_OS_WIN32)
-    qreal dpr = qApp->devicePixelRatio();
+    createStandardCursors(devicePixelRatio());
+#if (QT_VERSION >= 0x050000)
+    connect(this, &View3DInventorViewer::devicePixelRatioChanged,
+            this, &View3DInventorViewer::createStandardCursors);
 #endif
-    QBitmap cursor = QBitmap::fromData(QSize(ROTATE_WIDTH, ROTATE_HEIGHT), rotate_bitmap);
-    QBitmap mask = QBitmap::fromData(QSize(ROTATE_WIDTH, ROTATE_HEIGHT), rotate_mask_bitmap);
-#if defined(Q_OS_WIN32)
-    cursor.setDevicePixelRatio(dpr);
-    mask.setDevicePixelRatio(dpr);
-#endif
-    spinCursor = QCursor(cursor, mask, ROTATE_HOT_X, ROTATE_HOT_Y);
 
-    cursor = QBitmap::fromData(QSize(ZOOM_WIDTH, ZOOM_HEIGHT), zoom_bitmap);
-    mask = QBitmap::fromData(QSize(ZOOM_WIDTH, ZOOM_HEIGHT), zoom_mask_bitmap);
-#if defined(Q_OS_WIN32)
-    cursor.setDevicePixelRatio(dpr);
-    mask.setDevicePixelRatio(dpr);
-#endif
-    zoomCursor = QCursor(cursor, mask, ZOOM_HOT_X, ZOOM_HOT_Y);
-
-    cursor = QBitmap::fromData(QSize(PAN_WIDTH, PAN_HEIGHT), pan_bitmap);
-    mask = QBitmap::fromData(QSize(PAN_WIDTH, PAN_HEIGHT), pan_mask_bitmap);
-#if defined(Q_OS_WIN32)
-    cursor.setDevicePixelRatio(dpr);
-    mask.setDevicePixelRatio(dpr);
-#endif
-    panCursor = QCursor(cursor, mask, PAN_HOT_X, PAN_HOT_Y);
     naviCube = new NaviCube(this);
     naviCubeEnabled = true;
 }
@@ -699,6 +679,35 @@ View3DInventorViewer::~View3DInventorViewer()
     delete glAction;
 }
 
+void View3DInventorViewer::createStandardCursors(double dpr)
+{
+    QBitmap cursor = QBitmap::fromData(QSize(ROTATE_WIDTH, ROTATE_HEIGHT), rotate_bitmap);
+    QBitmap mask = QBitmap::fromData(QSize(ROTATE_WIDTH, ROTATE_HEIGHT), rotate_mask_bitmap);
+#if defined(Q_OS_WIN32)
+    cursor.setDevicePixelRatio(dpr);
+    mask.setDevicePixelRatio(dpr);
+#else
+    Q_UNUSED(dpr)
+#endif
+    spinCursor = QCursor(cursor, mask, ROTATE_HOT_X, ROTATE_HOT_Y);
+
+    cursor = QBitmap::fromData(QSize(ZOOM_WIDTH, ZOOM_HEIGHT), zoom_bitmap);
+    mask = QBitmap::fromData(QSize(ZOOM_WIDTH, ZOOM_HEIGHT), zoom_mask_bitmap);
+#if defined(Q_OS_WIN32)
+    cursor.setDevicePixelRatio(dpr);
+    mask.setDevicePixelRatio(dpr);
+#endif
+    zoomCursor = QCursor(cursor, mask, ZOOM_HOT_X, ZOOM_HOT_Y);
+
+    cursor = QBitmap::fromData(QSize(PAN_WIDTH, PAN_HEIGHT), pan_bitmap);
+    mask = QBitmap::fromData(QSize(PAN_WIDTH, PAN_HEIGHT), pan_mask_bitmap);
+#if defined(Q_OS_WIN32)
+    cursor.setDevicePixelRatio(dpr);
+    mask.setDevicePixelRatio(dpr);
+#endif
+    panCursor = QCursor(cursor, mask, PAN_HOT_X, PAN_HOT_Y);
+}
+
 void View3DInventorViewer::aboutToDestroyGLContext()
 {
     if (naviCube) {
diff --git a/src/Gui/View3DInventorViewer.h b/src/Gui/View3DInventorViewer.h
index c690b54346..97908837c8 100644
--- a/src/Gui/View3DInventorViewer.h
+++ b/src/Gui/View3DInventorViewer.h
@@ -426,6 +426,7 @@ private:
     static void drawArrow(void);
     void setCursorRepresentation(int mode);
     void aboutToDestroyGLContext();
+    void createStandardCursors(double);
 
 private:
     NaviCube* naviCube;