Wiresheet: mouse wheel scrolls the sheet, Shift + wheel scrolls sideways

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

main.py

@@ -903,6 +903,18 @@ def on_canvas_wheel_zoom(event):
     return "break"
 
 
+def on_canvas_wheel_scroll(event):
+    """Plain wheel pans the sheet up and down, Shift + wheel pans it sideways."""
+    if not event.delta:
+        return "break"
+    units = -1 if event.delta > 0 else 1
+    if event.state & 0x0001:
+        canvas.xview_scroll(units, "units")
+    else:
+        canvas.yview_scroll(units, "units")
+    return "break"
+
+
 # --- Event handlers ---
 
 def on_tree_select(event):
@@ -3364,6 +3376,12 @@ canvas.bind("<Double-1>", on_canvas_double_click)
 canvas.bind("<Control-MouseWheel>", on_canvas_wheel_zoom)
 canvas.bind("<Control-Button-4>", do_zoom_in)
 canvas.bind("<Control-Button-5>", do_zoom_out)
+canvas.bind("<MouseWheel>", on_canvas_wheel_scroll)
+canvas.bind("<Shift-MouseWheel>", on_canvas_wheel_scroll)
+canvas.bind("<Button-4>", lambda e: canvas.yview_scroll(-1, "units"))
+canvas.bind("<Button-5>", lambda e: canvas.yview_scroll(1, "units"))
+canvas.bind("<Shift-Button-4>", lambda e: canvas.xview_scroll(-1, "units"))
+canvas.bind("<Shift-Button-5>", lambda e: canvas.xview_scroll(1, "units"))
 
 paned_window.add(frame_editor, weight=3)