Make the 3D mouse pan and zoom the element editor too

The 3D mouse only acted on the diagram editor: SpaceMouseListener
ignored every other window, so the element editor did not move at
all (reported by scorpio810 in PR #635 with a SpacePilot Pro).

applyMotion() now also handles a QETElementEditor, driving its
ElementView through the same scrollbar pan and a new
ElementView::zoom(factor), which keeps the wheel zoom's clamping.
The element editor's scene rect only covers what is on screen, so it
is grown before each pan sample, as its middle-button pan does;
without that the scrollbars have no range and the pan does nothing.

Verified under Xvfb with an LD_PRELOAD stand-in for libspnav feeding
recorded motion samples: element editor zooms 1.63x for ten z=50
samples and pans; diagram editor screenshots are byte-identical to
master's for the same input.

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

sources/editor/elementview.cpp

@@ -117,6 +117,18 @@ void ElementView::scaleClamped(qreal factor)
 	scale(factor, factor);
 }
 
+/**
+	@brief ElementView::zoom
+	Zoom by an arbitrary factor, for a continuous input such as a 3D mouse.
+	Same clamping as the wheel zoom.
+	@param zoom_factor : > 1 zooms in, < 1 zooms out
+*/
+void ElementView::zoom(qreal zoom_factor)
+{
+	adjustSceneRect();
+	scaleClamped(zoom_factor);
+}
+
 /**
 	Agrandit le schema (+33% = inverse des -25 % de zoomMoins())
 */

sources/editor/elementview.h

@@ -41,6 +41,7 @@ class ElementView : public QGraphicsView {
 	ElementScene *scene() const;
 	void setScene(ElementScene *);
 	QRectF viewedSceneRect() const;
+	void zoom(qreal zoom_factor);
 	
 	protected:
 	void mousePressEvent(QMouseEvent *) override;

sources/spacemouse/spacemouselistener.cpp

@@ -24,6 +24,8 @@
 #endif
 
 #include "../diagramview.h"
+#include "../editor/elementview.h"
+#include "../editor/ui/qetelementeditor.h"
 #include "../projectview.h"
 #include "../qetdiagrameditor.h"
 #include "../shortcutmanager.h"
@@ -47,6 +49,16 @@ namespace {
 		//one-line fix once someone with a device tries it.
 	constexpr qreal ZOOM_DIVISOR = 1000.0;
 	constexpr qreal PAN_SCALE = 1.0;
+
+		//Pan a view by one motion sample, through its scrollbars -- the same
+		//way both editors' own middle-button drag pans them.
+	void panView(QGraphicsView *view, int dx, int dy)
+	{
+		view->horizontalScrollBar()->setValue(
+			view->horizontalScrollBar()->value() - qRound(dx * PAN_SCALE));
+		view->verticalScrollBar()->setValue(
+			view->verticalScrollBar()->value() - qRound(dy * PAN_SCALE));
+	}
 }
 
 /**
@@ -96,11 +108,12 @@ qreal SpaceMouseListener::zoomFactorForZAxis(int z)
 
 /**
 	@brief SpaceMouseListener::applyMotion
-	Apply one motion sample to whichever DiagramView is currently active.
+	Apply one motion sample to the view of the active window: the current
+	folio of a diagram editor, or the drawing of an element editor.
 	X/Y translation pans it, Z translation zooms it -- the same two
-	primitives (scrollbars, DiagramView::zoom()) DiagramView::wheelEvent()
-	already drives from a physical wheel, so there is no new navigation
-	logic here, only a new input source feeding the existing one.
+	primitives (scrollbars, zoom()) each view's wheelEvent() already drives
+	from a physical wheel, so there is no new navigation logic here, only a
+	new input source feeding the existing one.
 
 	Which of a device's three translation axes is "left/right" vs
 	"forward/back" vs "up/down", and their sign, is a hardware convention
@@ -112,31 +125,46 @@ qreal SpaceMouseListener::zoomFactorForZAxis(int z)
 */
 void SpaceMouseListener::applyMotion(int dx, int dy, int dz)
 {
-	auto *editor = qobject_cast<QETDiagramEditor *>(qApp->activeWindow());
-	if (!editor) {
-		return;
-	}
+	QWidget *window = qApp->activeWindow();
 
-	ProjectView *project_view = editor->currentProjectView();
-	if (!project_view) {
-		return;
-	}
-
-	DiagramView *view = project_view->currentDiagram();
-	if (!view) {
-		return;
-	}
-
-	if (dx || dy)
+	if (auto *editor = qobject_cast<QETDiagramEditor *>(window))
 	{
-		view->horizontalScrollBar()->setValue(
-			view->horizontalScrollBar()->value() - qRound(dx * PAN_SCALE));
-		view->verticalScrollBar()->setValue(
-			view->verticalScrollBar()->value() - qRound(dy * PAN_SCALE));
-	}
+		ProjectView *project_view = editor->currentProjectView();
+		if (!project_view) {
+			return;
+		}
 
-	if (dz) {
-		view->zoom(zoomFactorForZAxis(dz));
+		DiagramView *view = project_view->currentDiagram();
+		if (!view) {
+			return;
+		}
+
+		if (dx || dy) {
+			panView(view, dx, dy);
+		}
+		if (dz) {
+			view->zoom(zoomFactorForZAxis(dz));
+		}
+	}
+	else if (auto *element_editor = qobject_cast<QETElementEditor *>(window))
+	{
+		ElementView *view = element_editor->elementView();
+		if (!view) {
+			return;
+		}
+
+		if (dx || dy)
+		{
+				//The element editor's scene rect only just covers what is
+				//on screen, so grow it before each sample, as its own
+				//middle-button pan does on release -- otherwise the
+				//scrollbars have no range and the pan does nothing.
+			view->adjustSceneRect();
+			panView(view, dx, dy);
+		}
+		if (dz) {
+			view->zoom(zoomFactorForZAxis(dz));
+		}
 	}
 }
 

sources/spacemouse/spacemouselistener.h

@@ -25,16 +25,16 @@ class SpaceMouseBackend;
 /**
 	@brief The SpaceMouseListener class
 	https://github.com/qelectrotech/qelectrotech-source-mirror/discussions/599 :
-	bridges a 3Dconnexion SpaceMouse/SpacePilot 6-DOF device to
-	DiagramView's existing pan/zoom primitives (the same
-	horizontalScrollBar()/verticalScrollBar()/zoom() calls
-	DiagramView::wheelEvent() already uses for a physical wheel), and its
+	bridges a 3Dconnexion SpaceMouse/SpacePilot 6-DOF device to the
+	existing pan/zoom primitives of DiagramView and ElementView (the same
+	horizontalScrollBar()/verticalScrollBar()/zoom() calls their
+	wheelEvent() already uses for a physical wheel), and its
 	buttons to named QET actions via ShortcutManager -- the same registry
 	keyboard shortcuts already use, so a device button can trigger anything
 	in that registry (undo, redo, rotate selection, ...) without QET having
 	a second, device-specific action list.
 
-	Everything here is platform-independent: which DiagramView to apply
+	Everything here is platform-independent: which view to apply
 	motion to, the pan/zoom calls, the Z-to-zoom-factor mapping, and button
 	dispatch via SpaceMouseButtonMap + ShortcutManager. Talking to the
 	actual device driver is a SpaceMouseBackend's job (see its class
@@ -73,7 +73,7 @@ class SpaceMouseListener : public QObject
 
 	private slots:
 			/// Apply one motion sample -- from whichever backend is in use
-			/// -- to whichever DiagramView is currently active.
+			/// -- to the view of the active diagram or element editor.
 		void applyMotion(int dx, int dy, int dz);
 
 			/// Look up which action id, if any, SpaceMouseButtonMap binds