From 0a40159aa80355e9b20c5ee701f16d04e89976ff Mon Sep 17 00:00:00 2001
From: ruyer <maxence.ruyer@esrf.fr>
Date: Wed, 17 Jun 2026 17:21:58 +0200
Subject: [PATCH] [PlotWidget] Allow directive zoom with shortcut ALT and SHIFT
 like h5web

---
 src/silx/gui/plot/PlotInteraction.py        | 20 +++++++++++++++-----
 src/silx/gui/plot/backends/BackendOpenGL.py |  2 +-
 src/silx/gui/plot/tools/menus.py            |  6 +++---
 3 files changed, 19 insertions(+), 9 deletions(-)

diff --git a/src/silx/gui/plot/PlotInteraction.py b/src/silx/gui/plot/PlotInteraction.py
index ef8d203c29..e2648d955a 100644
--- a/src/silx/gui/plot/PlotInteraction.py
+++ b/src/silx/gui/plot/PlotInteraction.py
@@ -1867,18 +1867,28 @@ def _onWheel(self, x: float, y: float, angle: float):
         if not self.isZoomOnWheelEnabled():
             return
 
+        if angle == 0:
+            return
         plotWidget = self.parent()
         if plotWidget is None:
             return
 
         # All axes are enabled if keep aspect ratio is on
-        enabledAxes = (
-            EnabledAxes()
-            if plotWidget.isKeepDataAspectRatio()
-            else self.getZoomEnabledAxes()
-        )
+        if plotWidget.isKeepDataAspectRatio():
+            enabledAxes = EnabledAxes()
+        else:
+            modifiers = qt.QApplication.keyboardModifiers()
+            shiftPressed = modifiers & qt.Qt.ShiftModifier
+            altPressed = modifiers & qt.Qt.AltModifier
+            if shiftPressed or altPressed:
+                enabledAxes = EnabledAxes(
+                    xaxis=altPressed, yaxis=shiftPressed, y2axis=shiftPressed
+                )
+            else:
+                enabledAxes = self.getZoomEnabledAxes()
         if enabledAxes.isDisabled():
             return
 
         scale = 1.1 if angle > 0 else 1.0 / 1.1
+
         applyZoomToPlot(plotWidget, scale, (x, y), enabledAxes)
diff --git a/src/silx/gui/plot/backends/BackendOpenGL.py b/src/silx/gui/plot/backends/BackendOpenGL.py
index f080746a66..4fdb11a7b9 100755
--- a/src/silx/gui/plot/backends/BackendOpenGL.py
+++ b/src/silx/gui/plot/backends/BackendOpenGL.py
@@ -323,7 +323,7 @@ def mouseReleaseEvent(self, event):
         event.accept()
 
     def wheelEvent(self, event):
-        delta = event.angleDelta().y()
+        delta = event.angleDelta().x() + event.angleDelta().y()
         angleInDegrees = delta / 8.0
         x, y = qt.getMouseEventPosition(event)
         self._plot.onMouseWheel(x, y, angleInDegrees)
diff --git a/src/silx/gui/plot/tools/menus.py b/src/silx/gui/plot/tools/menus.py
index ca8a1ba31f..6373f7040d 100644
--- a/src/silx/gui/plot/tools/menus.py
+++ b/src/silx/gui/plot/tools/menus.py
@@ -52,9 +52,9 @@ def __init__(self, plot: PlotWidget, parent: qt.QWidget | None = None):
         self.__plotRef = weakref.ref(plot)
 
         self.addSection("Enabled axes")
-        self.__xAxisAction = qt.QAction("X axis", parent=self)
-        self.__yAxisAction = qt.QAction("Y left axis", parent=self)
-        self.__y2AxisAction = qt.QAction("Y right axis", parent=self)
+        self.__xAxisAction = qt.QAction("X axis (alt)", parent=self)
+        self.__yAxisAction = qt.QAction("Y left axis (shift)", parent=self)
+        self.__y2AxisAction = qt.QAction("Y right axis (shift)", parent=self)
 
         for action in (self.__xAxisAction, self.__yAxisAction, self.__y2AxisAction):
             action.setCheckable(True)