From 53c2ced83ebc74b87443487540b22cd94e4db4e3 Mon Sep 17 00:00:00 2001
From: Rebecca Breu <rebecca@rbreu.de>
Date: Sun, 3 Mar 2024 13:29:52 +0100
Subject: [PATCH] Added panning via scroll wheel

---
 CHANGELOG.rst                      | 10 ++++++++++
 beeref/documentation/controls.html |  6 ++++--
 beeref/view.py                     | 14 ++++++++++++--
 tests/test_view.py                 | 25 ++++++++++++++++++++++++-
 4 files changed, 50 insertions(+), 5 deletions(-)

diff --git a/CHANGELOG.rst b/CHANGELOG.rst
index e31373e..bb00972 100644
--- a/CHANGELOG.rst
+++ b/CHANGELOG.rst
@@ -10,6 +10,9 @@ Added
   clipboard in hex format (Images -> Sample Color)
 * Added notification when attempting to paste from an empty or
   unusable clipboard
+* Panning via scrollwheel:
+  * Scroll wheel without modifiers: pan vertically
+  * Scroll wheel + Shift: pan horizontally
 
 
 Fixed
@@ -23,6 +26,13 @@ Fixed
   would scale with the image and get potentially very thick.
 
 
+Changed
+-------
+
+* Using the scroll wheel will now only zoom when Ctrl is pressed,
+  instead of zooming all the time regardless of modifiers.
+
+
 0.3.2 - 2024-01-21
 ==================
 
diff --git a/beeref/documentation/controls.html b/beeref/documentation/controls.html
index 0740be6..31e1f09 100644
--- a/beeref/documentation/controls.html
+++ b/beeref/documentation/controls.html
@@ -2,13 +2,15 @@
 
 <p>
   Middle Click + Drag<br/>
-  Alt + Left Click + Drag
+  Alt + Left Click + Drag<br/>
+  Mouse Wheel (pan vertically)<br/>
+  Shift + Mouse wheel (pan horizontally)
 </p>
 
 <h4>Zoom Canvas</h4>
 
 <p>
-  Mouse wheel up/down<br/>
+  Ctrl + Mouse Wheel<br/>
   Ctrl + Middle Click + Drag
 </p>
 
diff --git a/beeref/view.py b/beeref/view.py
index e1d1d85..3dbdedc 100644
--- a/beeref/view.py
+++ b/beeref/view.py
@@ -748,8 +748,18 @@ class BeeGraphicsView(MainControlsMixin,
         self.reset_previous_transform()
 
     def wheelEvent(self, event):
-        self.zoom(event.angleDelta().y(), event.position())
-        event.accept()
+        if event.modifiers() == Qt.KeyboardModifier.ControlModifier:
+            self.zoom(event.angleDelta().y(), event.position())
+            event.accept()
+            return
+        if event.modifiers() == Qt.KeyboardModifier.NoModifier:
+            self.pan(QtCore.QPointF(0, 0.5 * event.angleDelta().y()))
+            event.accept()
+            return
+        if event.modifiers() == Qt.KeyboardModifier.ShiftModifier:
+            self.pan(QtCore.QPointF(0.5 * event.angleDelta().y(), 0))
+            event.accept()
+            return
 
     def mousePressEvent(self, event):
         if self.mousePressEventMainControls(event):
diff --git a/tests/test_view.py b/tests/test_view.py
index edb4c51..490809b 100644
--- a/tests/test_view.py
+++ b/tests/test_view.py
@@ -930,15 +930,38 @@ def test_delta_zero(pan_mock, reset_mock, view, item):
 
 
 @patch('beeref.view.BeeGraphicsView.zoom')
-def test_wheel_event(zoom_mock, view):
+def test_wheel_event_zoom(zoom_mock, view):
     event = MagicMock()
     event.angleDelta.return_value = QtCore.QPointF(0.0, 40.0)
     event.position.return_value = QtCore.QPointF(10.0, 20.0)
+    event.modifiers.return_value = Qt.KeyboardModifier.ControlModifier
     view.wheelEvent(event)
     zoom_mock.assert_called_once_with(40, QtCore.QPointF(10.0, 20.0))
     event.accept.assert_called_once_with()
 
 
+@patch('beeref.view.BeeGraphicsView.pan')
+def test_wheel_event_pan_vertically(pan_mock, view):
+    event = MagicMock()
+    event.angleDelta.return_value = QtCore.QPointF(0.0, 40.0)
+    event.position.return_value = QtCore.QPointF(10.0, 20.0)
+    event.modifiers.return_value = Qt.KeyboardModifier.NoModifier
+    view.wheelEvent(event)
+    pan_mock.assert_called_once_with(QtCore.QPointF(0, 20))
+    event.accept.assert_called_once_with()
+
+
+@patch('beeref.view.BeeGraphicsView.pan')
+def test_wheel_event_pan_horizontally(pan_mock, view):
+    event = MagicMock()
+    event.angleDelta.return_value = QtCore.QPointF(0.0, 40.0)
+    event.position.return_value = QtCore.QPointF(10.0, 20.0)
+    event.modifiers.return_value = Qt.KeyboardModifier.ShiftModifier
+    view.wheelEvent(event)
+    pan_mock.assert_called_once_with(QtCore.QPointF(20, 0))
+    event.accept.assert_called_once_with()
+
+
 @patch('PyQt6.QtWidgets.QGraphicsView.mousePressEvent')
 def test_mouse_press_zoom(mouse_event_mock, view):
     event = MagicMock()