Add editable resize/rotate/skew handles for shapes and images

Shapes and images can now be resized, rotated, and skewed directly on the canvas, not just moved. Both share one small transform struct (rotation, then skew, then scale, anchored on a movable pivot) and one handle widget, so a corner drag, an edge skew, or grabbing the rotate handle behaves the same way and runs through the same matrix math everywhere, instead of every item type reinventing its own. Shapes also gained a proper pen tool (bezier paths, corner/smooth/ symmetric nodes), arc support, and mirroring. Images gained non-destructive cropping and colour-keyed transparency, both remember their own settings, so reopening the dialog picks up where you left off instead of starting over. Properties dialogs for both were extended to match (position, size, angle, skew), with undo/redo wired through for every handle drag. Old XML files can read easily as the transformation is only added if needed and the old syntax is still used and understood if it is not needed.
2026-09-28 04:54:13 +02:00 · 2026-09-05 15:48:28 +02:00
parent 823468826d
commit 6b577ee757
29 changed files with 6784 additions and 433 deletions
@@ -19,8 +19,16 @@

 #include "../diagram.h"
 #include "../lastusedstyle.h"
+#include "../qetapp.h"
+#include "../qetdiagrameditor.h"
 #include "../undocommand/addgraphicsobjectcommand.h"

+#include <QGraphicsEllipseItem>
+#include <QGuiApplication>
+#include <QKeyEvent>
+#include <QStatusBar>
+#include <QTimer>
+
 /**
 	@brief DiagramEventAddShape::DiagramEventAddShape
 	Default constructor
@@ -36,6 +44,18 @@ DiagramEventAddShape::DiagramEventAddShape(Diagram *diagram, QetShapeItem::Shape
 {
 	m_running = true;
 	init();
+	// Deferred to the next event-loop iteration, not shown immediately:
+	// Diagram::setEventInterface() destroys whatever tool was
+	// previously active *after* this constructor returns, and that
+	// previous tool's own destructor clears the status bar (see
+	// ~DiagramEventAddShape() below) -- an immediate show here would
+	// just get wiped out moments later by that cleanup. Letting the old
+	// tool's teardown finish first, then showing this one's message, is
+	// the same fix already used for the tooltip-flicker issue in
+	// QetShapeItem::refreshInteractionHints(), applied to the same
+	// class of "something later in the same call chain undoes what I
+	// just did" ordering problem.
+	QTimer::singleShot(0, this, [this]() { updateCreationHint(); });
 }

 /**
@@ -50,11 +70,123 @@ DiagramEventAddShape::~DiagramEventAddShape()
 	}
 	delete m_help_horiz;
 	delete m_help_verti;
+	delete m_center_marker;
+
+	if (m_diagram && !m_diagram->views().isEmpty())
+	{
+		if (auto *editor = QETApp::diagramEditorAncestorOf(m_diagram->views().constFirst()))
+			editor->statusBar()->clearMessage();
+	}

 	foreach (QGraphicsView *v, m_diagram->views())
 		v->setContextMenuPolicy(Qt::DefaultContextMenu);
 }

+/**
+	@brief DiagramEventAddShape::applyPosition
+	Applies a drag/click position to the in-progress shape, honouring two
+	modifiers that mirror how the very same shape can already be edited
+	afterward, once placed:
+	  - Ctrl, for Rectangle/Ellipse only: the first click becomes the
+	    shape's *center* rather than a corner, growing symmetrically as
+	    the cursor moves away from it -- the same meaning Ctrl already
+	    has on a Resize handle (anchor at center). Deliberately not
+	    offered for Line: unlike the Rectangle/Ellipse case, there's no
+	    established convention for "a line grows symmetrically from its
+	    middle" to justify it by, so Ctrl for Line means only free
+	    positioning (see the plain grid-snap check above), nothing more.
+	  - Shift, for Rectangle/Ellipse only: forces the bounding box square
+	    (so Ellipse becomes a true circle), using whichever of the two
+	    dragged dimensions is currently larger and mirroring that onto
+	    the other, preserving the direction the user is actually
+	    dragging in.
+	Both can combine (Ctrl+Shift: a centered square/circle). Whether or
+	not Ctrl is currently held, the non-anchored branch always rebuilds
+	from m_anchor_point rather than nudging the existing rect/line --
+	otherwise, if Ctrl had been held earlier in the same drag (moving the
+	shape's own first point to a mirrored position), releasing it would
+	leave that point stuck there instead of actually restoring it.
+*/
+void DiagramEventAddShape::applyPosition(const QPointF &pos, Qt::KeyboardModifiers mods)
+{
+	if (!m_shape_item)
+		return;
+
+	if (m_shape_type == QetShapeItem::Polygon)
+	{
+		// setP2() has its own dedicated Polygon handling: it moves the
+		// *last* vertex in place rather than setting a second point,
+		// which is exactly the live "next segment follows the mouse"
+		// preview -- the same idea DiagramEventAddPath's trailing
+		// preview node gives the pen tool. No Ctrl/Shift modifiers apply
+		// here (those are Rectangle/Ellipse/Line-specific below), so
+		// this is a direct, unconditional call.
+		m_shape_item->setP2(pos);
+		return;
+	}
+
+	// m_center_anchored is decided once, in mousePressEvent, not
+	// re-checked here on every call -- re-checking it live meant
+	// releasing Ctrl mid-drag (something you'd naturally do the moment
+	// your hand gets tired holding it, long before you're done resizing)
+	// silently snapped the shape back to corner-anchored, discarding
+	// what felt like an already-made decision. Deciding it once at the
+	// first click matches "I held Ctrl when I clicked, so this shape is
+	// centered" -- a single, predictable rule instead of a live toggle.
+	QPointF target = pos;
+
+	if ((mods & Qt::ShiftModifier)
+			&& (m_shape_type == QetShapeItem::Rectangle || m_shape_type == QetShapeItem::Ellipse))
+	{
+		const QPointF ref = m_anchor_point;
+		const qreal dx = target.x() - ref.x();
+		const qreal dy = target.y() - ref.y();
+		const qreal size = qMax(qAbs(dx), qAbs(dy));
+		target.setX(ref.x() + (dx < 0 ? -size : size));
+		target.setY(ref.y() + (dy < 0 ? -size : size));
+	}
+
+	if (m_center_anchored)
+	{
+		const QPointF mirrored = 2 * m_anchor_point - target;
+		m_shape_item->setRect(QRectF(mirrored, target));
+	}
+	else
+	{
+		if (m_shape_type == QetShapeItem::Line)
+			m_shape_item->setLine(QLineF(m_anchor_point, target));
+		else
+			m_shape_item->setRect(QRectF(m_anchor_point, target));
+	}
+}
+
+/**
+	@brief DiagramEventAddShape::showCenterMarker
+	Small, filled marker at the anchor point, shown only while Ctrl-
+	anchoring is actually in effect right now (see applyPosition()) --
+	doubling as live confirmation that it is, rather than leaving the
+	user to infer it purely from how the shape happens to be growing.
+*/
+void DiagramEventAddShape::showCenterMarker(const QPointF &scenePos)
+{
+	if (!m_center_marker)
+	{
+		m_center_marker = new QGraphicsEllipseItem(-4, -4, 8, 8);
+		QPen pen(Qt::red);
+		pen.setCosmetic(true);
+		m_center_marker->setPen(pen);
+		m_center_marker->setBrush(Qt::red);
+		m_diagram->addItem(m_center_marker);
+	}
+	m_center_marker->setPos(scenePos);
+}
+
+void DiagramEventAddShape::hideCenterMarker()
+{
+	delete m_center_marker;
+	m_center_marker = nullptr;
+}
+
 /**
 	@brief DiagramEventAddShape::mousePressEvent
 	Action when mouse is pressed
@@ -67,7 +199,14 @@ void DiagramEventAddShape::mousePressEvent(QGraphicsSceneMouseEvent *event)
 	}

 	QPointF pos = event->scenePos();
-	if (event->modifiers() != Qt::ControlModifier) {
+	// A bitwise flag check, not exact equality: modifiers() == Ctrl
+	// alone fails the moment any other key (Shift for the square/circle
+	// lock, or an incidental platform flag) is also held, silently
+	// falling through to snapToGrid() even though Ctrl is held --
+	// exactly what made Ctrl+Shift together feel "frozen" (both grid-
+	// snapped *and* square-locked, quantizing to whichever is coarser)
+	// and made "Ctrl = free positioning" not actually hold up.
+	if (!(event->modifiers() & Qt::ControlModifier)) {
 		pos = Diagram::snapToGrid(pos);
 	}

@@ -78,6 +217,15 @@ void DiagramEventAddShape::mousePressEvent(QGraphicsSceneMouseEvent *event)
 		if (!m_shape_item)
 		{
 			m_shape_item = new QetShapeItem(pos, pos, m_shape_type);
+			m_anchor_point = pos;
+			// Decided once, here, rather than re-checked on every mouse
+			// move for the rest of the drag -- see applyPosition()'s doc
+			// comment for why continuous re-checking made releasing Ctrl
+			// mid-drag feel like a bug rather than a deliberate choice.
+			m_center_anchored = (event->modifiers() & Qt::ControlModifier)
+					&& (m_shape_type == QetShapeItem::Rectangle || m_shape_type == QetShapeItem::Ellipse);
+			if (m_center_anchored)
+				showCenterMarker(m_anchor_point);
 				//Start from whatever pen/brush was last applied this
 				//session, rather than always the hardcoded default.
 			if (LastUsedStyle::hasShapePen()) {
@@ -87,6 +235,7 @@ void DiagramEventAddShape::mousePressEvent(QGraphicsSceneMouseEvent *event)
 				m_shape_item->setBrush(LastUsedStyle::shapeBrush());
 			}
 			m_diagram->addItem (m_shape_item);
+			updateCreationHint();
 			event->setAccepted(true);
 			return;
 		}
@@ -94,12 +243,14 @@ void DiagramEventAddShape::mousePressEvent(QGraphicsSceneMouseEvent *event)
 			//If current item isn't a polyline, add it with an undo command
 		if (m_shape_type != QetShapeItem::Polygon)
 		{
-			m_shape_item->setP2 (pos);
+			applyPosition(pos, event->modifiers());
 			if (m_shape_item->shapeType() == QetShapeItem::Rectangle || m_shape_item->shapeType() == QetShapeItem::Ellipse) {
 				m_shape_item->setRect(m_shape_item->rect().normalized());
 			}
 			m_diagram->undoStack().push (new AddGraphicsObjectCommand(m_shape_item, m_diagram));
 			m_shape_item = nullptr; //< set to nullptr for create new shape at next left clic
+			hideCenterMarker();
+			updateCreationHint();
 		}
 			//Else add a new point to polyline
 		else
@@ -125,18 +276,76 @@ void DiagramEventAddShape::mouseMoveEvent(QGraphicsSceneMouseEvent *event)
 {
 	updateHelpCross(event->scenePos());

+	// Re-asserted on every move, not just once at activation: Qt's own
+	// built-in "show an action's statusTip on hover" has its own
+	// internal "restore whatever was there before" logic for when the
+	// hover ends. Since our message is shown *during* that same hover
+	// session (the user is still over the toolbar icon when the
+	// deferred constructor-time call fires), Qt's hover-tracking has no
+	// idea we changed the status bar in the meantime -- the moment the
+	// mouse leaves the icon for the canvas, it "restores" to whatever it
+	// remembers being there before its own tip started, which is stale
+	// and empty, silently overwriting ours. Re-showing it here, on every
+	// move within the canvas, simply outlasts that one-time restore.
+	updateCreationHint();
+
 	if (m_shape_item && event->buttons() == Qt::NoButton)
 	{
+		m_last_mouse_scene_pos = event->scenePos();   // raw, before snapping -- see reapplyLastPosition()
+
 		QPointF pos = event->scenePos();
-		if (event->modifiers() != Qt::ControlModifier) {
+		if (!(event->modifiers() & Qt::ControlModifier)) {
 			pos = Diagram::snapToGrid(pos);
 		}

-		m_shape_item->setP2 (pos);
+		applyPosition(pos, event->modifiers());
 		event->setAccepted(true);
 	}
 }

+/**
+	@brief DiagramEventAddShape::keyPressEvent / keyReleaseEvent
+	Pressing or releasing Shift (the square/circle lock) does nothing
+	visible on its own -- applyPosition() only ever runs from
+	mouseMoveEvent, so without this, a keyboard-only change just sits
+	there until the next, often incidental, pixel of mouse movement
+	brings the shape in line with it. That's exactly what looked like a
+	freeze: holding Shift while the mouse is genuinely still produces no
+	visible change (correctly -- nothing has moved), and it only
+	"unsticks" once the mouse moves again, which released keys tend to
+	coincide with purely by hand tremor, not because releasing itself
+	did anything. Re-running the last known mouse position through
+	applyPosition() here makes the key press or release itself the
+	trigger, giving immediate feedback instead of waiting on chance.
+*/
+void DiagramEventAddShape::keyPressEvent(QKeyEvent *event)
+{
+	reapplyLastPosition(event);
+}
+
+void DiagramEventAddShape::keyReleaseEvent(QKeyEvent *event)
+{
+	reapplyLastPosition(event);
+}
+
+void DiagramEventAddShape::reapplyLastPosition(QKeyEvent *event)
+{
+	if (!m_shape_item || (event->key() != Qt::Key_Shift && event->key() != Qt::Key_Control))
+		return;
+
+	// A fresh, global query, not event->modifiers(): for a press/release
+	// of a modifier key itself, whether that key is already reflected in
+	// the key event's own modifiers() is ambiguous and platform-
+	// dependent -- the same reason Diagram::snapToGrid() queries this
+	// directly rather than trusting a passed-in modifiers() value.
+	const Qt::KeyboardModifiers mods = QGuiApplication::keyboardModifiers();
+	QPointF pos = m_last_mouse_scene_pos;
+	if (!(mods & Qt::ControlModifier))
+		pos = Diagram::snapToGrid(pos);
+
+	applyPosition(pos, mods);
+}
+
 /**
 	@brief DiagramEventAddShape::mouseReleaseEvent
 	Action when mouse button is released
@@ -155,7 +364,7 @@ void DiagramEventAddShape::mouseReleaseEvent(QGraphicsSceneMouseEvent *event)
 				m_shape_item->removePoints();

 				QPointF pos = event->scenePos();
-				if (event->modifiers() != Qt::ControlModifier)
+				if (!(event->modifiers() & Qt::ControlModifier))
 					pos = Diagram::snapToGrid(pos);

 				m_shape_item->setP2(pos); //Set the new last point under the cursor
@@ -167,6 +376,8 @@ void DiagramEventAddShape::mouseReleaseEvent(QGraphicsSceneMouseEvent *event)
 			m_diagram->removeItem(m_shape_item);
 			delete m_shape_item;
 			m_shape_item = nullptr;
+			hideCenterMarker();
+			updateCreationHint();
 			event->setAccepted(true);
 			return;
 		}
@@ -203,6 +414,8 @@ void DiagramEventAddShape::mouseDoubleClickEvent(QGraphicsSceneMouseEvent *event
 		}
 		m_diagram->undoStack().push (new AddGraphicsObjectCommand(m_shape_item, m_diagram));
 		m_shape_item = nullptr; //< set to nullptr for create new shape at next left clic
+		hideCenterMarker();
+		updateCreationHint();
 		event->setAccepted(true);
 	}
 }
@@ -213,6 +426,59 @@ void DiagramEventAddShape::init()
 		v->setContextMenuPolicy(Qt::NoContextMenu);
 }

+/**
+	@brief DiagramEventAddShape::updateCreationHint
+	Shows whichever of beforeClickHint()/afterClickHint() matches the
+	current phase -- there was previously either no message at all
+	(Line/Rectangle/Ellipse) or a single static one that never changed
+	regardless of progress (Polygon, set externally in
+	QETDiagramEditor::addItemGroupTriggered()); this replaces both with
+	one phase-aware message per shape type, managed by the tool itself.
+*/
+void DiagramEventAddShape::updateCreationHint() const
+{
+	if (!m_diagram || m_diagram->views().isEmpty())
+		return;
+	if (auto *editor = QETApp::diagramEditorAncestorOf(m_diagram->views().constFirst()))
+		editor->statusBar()->showMessage(m_shape_item ? afterClickHint() : beforeClickHint());
+}
+
+QString DiagramEventAddShape::beforeClickHint() const
+{
+	switch (m_shape_type)
+	{
+		case QetShapeItem::Line:
+			return tr("Clic gauche : positionner le point de départ (Ctrl = position libre)");
+		case QetShapeItem::Rectangle:
+		case QetShapeItem::Ellipse:
+			return tr("Clic gauche : positionner le premier coin (Ctrl = point central, position libre)");
+		case QetShapeItem::Polygon:
+			return tr("Clic gauche : positionner le premier point (Ctrl = position libre)");
+		default:
+			return QString();
+	}
+}
+
+QString DiagramEventAddShape::afterClickHint() const
+{
+	switch (m_shape_type)
+	{
+		case QetShapeItem::Line:
+			return tr("Clic gauche : positionner le point final (Ctrl = position libre) ; clic droit : annuler");
+		case QetShapeItem::Rectangle:
+			return tr("Clic gauche : positionner le coin opposé (Maj = carré, "
+					"Ctrl = depuis le centre + position libre, Ctrl+Maj = carré centré) ; clic droit : annuler");
+		case QetShapeItem::Ellipse:
+			return tr("Clic gauche : positionner le coin opposé (Maj = cercle, "
+					"Ctrl = depuis le centre + position libre, Ctrl+Maj = cercle centré) ; clic droit : annuler");
+		case QetShapeItem::Polygon:
+			return tr("Clic gauche : point suivant ; double-clic ou Entrée : terminer ; "
+					"clic droit : annuler le dernier point");
+		default:
+			return QString();
+	}
+}
+
 /**
 	@brief DiagramEventAddShape::updateHelpCross
 	Create and update the position of the cross to help user for draw new shape