Allow expanding, shrinking and growing selections

Via Selection > Expand/Shrink/Feather Selection. This opens a dialog
where you can input those parameters to manipulate an existing
selection.

Implements #1267 and #1306.

ChangeLog

@@ -84,6 +84,7 @@ Unreleased Version 2.2.2-pre
  * Fix: Make the fill tool not feather along canvas edge. Thanks Meru for reporting.
  * Server Feature: Allow specifying idleOverride and allowWeb in session templates. Thanks MorrowShore for suggesting.
  * Feature: Allow shrinking fills and magic wand selections. Thanks Meru for suggesting.
+ * Feature: New dialog Selection > Expand/Shrink/Feather Selection that alters selections accordingly. Thanks MorrowShore for suggesting.
 
 2024-02-25 Version 2.2.2-beta.1
  * Server Feature: Allow adding a message when kicking someone through the admin API.

src/desktop/CMakeLists.txt

@@ -124,6 +124,8 @@ target_sources(drawpile PRIVATE
 	dialogs/resetdialog.h
 	dialogs/resizedialog.cpp
 	dialogs/resizedialog.h
+	dialogs/selectionalterdialog.cpp
+	dialogs/selectionalterdialog.h
 	dialogs/serverlogdialog.cpp
 	dialogs/serverlogdialog.h
 	dialogs/sessionundodepthlimitdialog.cpp

src/desktop/dialogs/selectionalterdialog.cpp

@@ -0,0 +1,146 @@
+// SPDX-License-Identifier: GPL-3.0-or-later
+#include "desktop/dialogs/selectionalterdialog.h"
+#include "desktop/utils/widgetutils.h"
+#include "desktop/widgets/groupedtoolbutton.h"
+#include <QButtonGroup>
+#include <QCheckBox>
+#include <QDialogButtonBox>
+#include <QHBoxLayout>
+#include <QPushButton>
+#include <QSpinBox>
+#include <QVBoxLayout>
+
+namespace dialogs {
+
+SelectionAlterDialog::SelectionAlterDialog(QWidget *parent)
+	: QDialog(parent)
+{
+	setWindowModality(Qt::WindowModal);
+	QVBoxLayout *layout = new QVBoxLayout(this);
+
+	QHBoxLayout *expandLayout = new QHBoxLayout;
+	expandLayout->setSpacing(0);
+
+	m_expandSpinner = new QSpinBox;
+	m_expandSpinner->setRange(0, 9999);
+	m_expandSpinner->setValue(getIntProperty(parent, PROP_EXPAND));
+	m_expandSpinner->setSuffix(tr("px"));
+	expandLayout->addWidget(m_expandSpinner, 1);
+	connect(
+		m_expandSpinner, QOverload<int>::of(&QSpinBox::valueChanged), this,
+		&SelectionAlterDialog::updateControls);
+
+	expandLayout->addSpacing(3);
+
+	widgets::GroupedToolButton *expandButton =
+		new widgets::GroupedToolButton(widgets::GroupedToolButton::GroupLeft);
+	expandButton->setIcon(QIcon::fromTheme("zoom-in"));
+	expandButton->setStatusTip(tr("Expand"));
+	expandButton->setToolTip(expandButton->statusTip());
+	expandButton->setCheckable(true);
+	expandButton->setChecked(!getBoolProperty(parent, PROP_SHRINK));
+	expandLayout->addWidget(expandButton);
+
+	widgets::GroupedToolButton *shrinkButton =
+		new widgets::GroupedToolButton(widgets::GroupedToolButton::GroupRight);
+	shrinkButton->setIcon(QIcon::fromTheme("zoom-out"));
+	shrinkButton->setStatusTip(tr("Shrink"));
+	shrinkButton->setToolTip(shrinkButton->statusTip());
+	shrinkButton->setCheckable(true);
+	shrinkButton->setChecked(!expandButton->isChecked());
+	expandLayout->addWidget(shrinkButton);
+
+	m_expandGroup = new QButtonGroup(this);
+	m_expandGroup->addButton(expandButton, 0);
+	m_expandGroup->addButton(shrinkButton, 1);
+	connect(
+		m_expandGroup,
+		QOverload<QAbstractButton *>::of(&QButtonGroup::buttonClicked), this,
+		&SelectionAlterDialog::updateControls);
+
+	layout->addLayout(expandLayout);
+
+	m_featherSpinner = new QSpinBox;
+	m_featherSpinner->setRange(0, 999);
+	m_featherSpinner->setValue(getIntProperty(parent, PROP_FEATHER));
+	//: "Feather" is a verb here, referring to blurring the selection.
+	m_featherSpinner->setPrefix(tr("Feather: "));
+	m_featherSpinner->setSuffix(tr("px"));
+	layout->addWidget(m_featherSpinner);
+	connect(
+		m_featherSpinner, QOverload<int>::of(&QSpinBox::valueChanged), this,
+		&SelectionAlterDialog::updateControls);
+
+	m_fromEdgeBox = new QCheckBox;
+	m_fromEdgeBox->setChecked(getBoolProperty(parent, PROP_FROM_EDGE));
+	layout->addWidget(m_fromEdgeBox);
+
+	layout->addStretch();
+
+	m_buttons =
+		new QDialogButtonBox(QDialogButtonBox::Ok | QDialogButtonBox::Cancel);
+	connect(
+		m_buttons, &QDialogButtonBox::accepted, this,
+		&SelectionAlterDialog::accept);
+	connect(
+		m_buttons, &QDialogButtonBox::rejected, this,
+		&SelectionAlterDialog::reject);
+	layout->addWidget(m_buttons);
+
+	connect(
+		this, &SelectionAlterDialog::accepted, this,
+		&SelectionAlterDialog::emitAlterSelectionRequested);
+
+	updateControls();
+	resize(300, 150);
+}
+
+bool SelectionAlterDialog::getBoolProperty(QWidget *w, const char *name)
+{
+	return w && w->property(name).toBool();
+}
+
+int SelectionAlterDialog::getIntProperty(QWidget *w, const char *name)
+{
+	return w ? w->property(name).toInt() : 0;
+}
+
+void SelectionAlterDialog::updateControls()
+{
+	bool shrink = m_expandGroup->checkedId() != 0;
+	bool haveExpand = m_expandSpinner->value() != 0;
+	bool haveFeather = m_featherSpinner->value() != 0;
+
+	if(shrink) {
+		m_expandSpinner->setPrefix(tr("Shrink: "));
+		//: "Feather" is a verb here, referring to blurring the selection.
+		m_fromEdgeBox->setText(tr("Shrink and feather from canvas edge"));
+	} else {
+		m_expandSpinner->setPrefix(tr("Expand: "));
+		//: "Feather" is a verb here, referring to blurring the selection.
+		m_fromEdgeBox->setText(tr("Feather from canvas edge"));
+	}
+
+	QPushButton *okButton = m_buttons->button(QDialogButtonBox::Ok);
+	if(okButton) {
+		okButton->setEnabled(haveExpand || haveFeather);
+	}
+}
+
+void SelectionAlterDialog::emitAlterSelectionRequested()
+{
+	bool shrink = m_expandGroup->checkedId() != 0;
+	int expand = m_expandSpinner->value();
+	int feather = m_featherSpinner->value();
+	bool fromEdge = m_fromEdgeBox->isChecked();
+	QWidget *pw = parentWidget();
+	if(pw) {
+		pw->setProperty(PROP_SHRINK, shrink);
+		pw->setProperty(PROP_EXPAND, expand);
+		pw->setProperty(PROP_FEATHER, feather);
+		pw->setProperty(PROP_FROM_EDGE, fromEdge);
+	}
+	emit alterSelectionRequested(expand * (shrink ? -1 : 1), feather, fromEdge);
+}
+
+}

src/desktop/dialogs/selectionalterdialog.h

@@ -0,0 +1,42 @@
+// SPDX-License-Identifier: GPL-3.0-or-later
+#ifndef DESKTOP_DIALOGS_SELECTIONALTERDIALOG_H
+#define DESKTOP_DIALOGS_SELECTIONALTERDIALOG_H
+#include <QDialog>
+
+class QButtonGroup;
+class QCheckBox;
+class QDialogButtonBox;
+class QSpinBox;
+
+namespace dialogs {
+
+class SelectionAlterDialog final : public QDialog {
+	Q_OBJECT
+public:
+	SelectionAlterDialog(QWidget *parent = nullptr);
+
+signals:
+	void alterSelectionRequested(int expand, int feather, bool fromEdge);
+
+private:
+	static constexpr char PROP_SHRINK[] = "SelectionAlterDialog_shrink";
+	static constexpr char PROP_EXPAND[] = "SelectionAlterDialog_expand";
+	static constexpr char PROP_FEATHER[] = "SelectionAlterDialog_feather";
+	static constexpr char PROP_FROM_EDGE[] = "SelectionAlterDialog_fromEdge";
+
+	static bool getBoolProperty(QWidget *w, const char *name);
+	static int getIntProperty(QWidget *w, const char *name);
+
+	void updateControls();
+	void emitAlterSelectionRequested();
+
+	QButtonGroup *m_expandGroup;
+	QSpinBox *m_expandSpinner;
+	QSpinBox *m_featherSpinner;
+	QCheckBox *m_fromEdgeBox;
+	QDialogButtonBox *m_buttons;
+};
+
+}
+
+#endif

src/desktop/mainwindow.cpp

@@ -14,6 +14,7 @@
 #include "desktop/dialogs/playbackdialog.h"
 #include "desktop/dialogs/resetdialog.h"
 #include "desktop/dialogs/resizedialog.h"
+#include "desktop/dialogs/selectionalterdialog.h"
 #include "desktop/dialogs/serverlogdialog.h"
 #include "desktop/dialogs/sessionsettings.h"
 #include "desktop/dialogs/sessionundodepthlimitdialog.h"
@@ -75,6 +76,7 @@
 #include "libclient/utils/customshortcutmodel.h"
 #include "libclient/utils/images.h"
 #include "libclient/utils/logging.h"
+#include "libclient/utils/selectionalteration.h"
 #include "libclient/utils/shortcutdetector.h"
 #include "libshared/util/networkaccess.h"
 #include "libshared/util/paths.h"
@@ -3165,6 +3167,7 @@ void MainWindow::updateSelectTransformActions()
 	getAction("selectinvert")->setEnabled(haveSelection);
 	getAction("selectlayerbounds")->setEnabled(!haveTransform);
 	getAction("selectlayercontents")->setEnabled(!haveTransform);
+	getAction("selectalter")->setEnabled(haveSelection && !haveTransform);
 	getAction("fillfgarea")->setEnabled(haveSelection);
 	getAction("recolorarea")->setEnabled(haveSelection);
 	getAction("colorerasearea")->setEnabled(haveSelection);
@@ -3176,6 +3179,16 @@ void MainWindow::updateSelectTransformActions()
 	getAction("transformrotateccw")->setEnabled(haveTransform);
 	getAction("transformshrinktoview")->setEnabled(haveTransform);
 	m_dockToolSettings->selectionSettings()->setActionEnabled(haveSelection);
+
+	if(!haveSelection || haveTransform) {
+		dialogs::SelectionAlterDialog *dlg =
+			findChild<dialogs::SelectionAlterDialog *>(
+				QStringLiteral("selectionalterdialog"),
+				Qt::FindDirectChildrenOnly);
+		if(dlg) {
+			dlg->deleteLater();
+		}
+	}
 }
 
 // clang-format off
@@ -3487,6 +3500,57 @@ void MainWindow::showUserInfoDialog(int userId)
 	dlg->show();
 }
 
+// clang-format on
+void MainWindow::showAlterSelectionDialog()
+{
+	QString name = QStringLiteral("selectionalterdialog");
+	dialogs::SelectionAlterDialog *dlg =
+		findChild<dialogs::SelectionAlterDialog *>(
+			name, Qt::FindDirectChildrenOnly);
+	if(dlg) {
+		dlg->activateWindow();
+		dlg->raise();
+	} else {
+		dlg = new dialogs::SelectionAlterDialog(this);
+		dlg->setAttribute(Qt::WA_DeleteOnClose);
+		dlg->setWindowTitle(getAction("selectalter")->text());
+		connect(
+			dlg, &dialogs::SelectionAlterDialog::alterSelectionRequested, this,
+			&MainWindow::alterSelection, Qt::QueuedConnection);
+		utils::showWindow(dlg);
+	}
+}
+
+void MainWindow::alterSelection(int expand, int feather, bool fromEdge)
+{
+	canvas::CanvasModel *canvas = m_doc->canvas();
+	if(canvas) {
+		SelectionAlteration *sa = new SelectionAlteration(
+			canvas->paintEngine()->viewCanvasState(), m_doc->client()->myId(),
+			canvas::CanvasModel::MAIN_SELECTION_ID, expand, feather, fromEdge);
+		sa->setAutoDelete(true);
+		connect(
+			sa, &SelectionAlteration::success, m_doc, &Document::selectMask);
+
+		QProgressDialog *progressDialog = new QProgressDialog(this);
+		progressDialog->setWindowModality(Qt::WindowModal);
+		progressDialog->setRange(0, 0);
+		progressDialog->setMinimumDuration(0);
+		progressDialog->setLabelText(tr("Altering selection…"));
+		connect(
+			sa, &SelectionAlteration::success, progressDialog,
+			&QProgressDialog::deleteLater);
+		connect(
+			sa, &SelectionAlteration::failure, progressDialog,
+			&QProgressDialog::deleteLater);
+		connect(
+			progressDialog, &QProgressDialog::canceled, sa,
+			&SelectionAlteration::cancel);
+		progressDialog->show();
+
+		QThreadPool::globalInstance()->start(sa);
+	}
+}
 
 void MainWindow::changeUndoDepthLimit()
 {
@@ -3504,7 +3568,7 @@ void MainWindow::changeUndoDepthLimit()
 		}
 	}
 }
-
+// clang-format off
 
 void MainWindow::updateDevToolsActions()
 {
@@ -4387,6 +4451,11 @@ void MainWindow::setupActions()
 		makeAction("selectlayercontents", tr("&Layer to Selection"))
 			.shortcut(Qt::SHIFT | Qt::Key_L)
 			.icon("edit-image");
+	QAction *selectalter =
+		//: "Feather" is a verb here, referring to blurring the selection.
+		makeAction("selectalter", tr("&Expand/Shrink/Feather Selection"))
+			.noDefaultShortcut()
+			.icon("zoom-select");
 	QAction *fillfgarea = makeAction("fillfgarea", tr("Fill Selection"))
 							  .shortcut(CTRL_KEY | Qt::Key_Comma);
 	QAction *recolorarea = makeAction("recolorarea", tr("Recolor Selection"))
@@ -4434,6 +4503,7 @@ void MainWindow::setupActions()
 	m_currentdoctools->addAction(selectinvert);
 	m_currentdoctools->addAction(selectlayerbounds);
 	m_currentdoctools->addAction(selectlayercontents);
+	m_currentdoctools->addAction(selectalter);
 
 	m_putimagetools->addAction(fillfgarea);
 	m_putimagetools->addAction(recolorarea);
@@ -4449,6 +4519,9 @@ void MainWindow::setupActions()
 	connect(
 		selectlayercontents, &QAction::triggered, m_doc,
 		&Document::selectLayerContents);
+	connect(
+		selectalter, &QAction::triggered, this,
+		&MainWindow::showAlterSelectionDialog);
 	connect(
 		fillfgarea, &QAction::triggered, this,
 		std::bind(
@@ -4475,6 +4548,7 @@ void MainWindow::setupActions()
 	selectMenu->addAction(selectinvert);
 	selectMenu->addAction(selectlayerbounds);
 	selectMenu->addAction(selectlayercontents);
+	selectMenu->addAction(selectalter);
 	selectMenu->addSeparator();
 	selectMenu->addAction(cleararea);
 	selectMenu->addAction(fillfgarea);

src/desktop/mainwindow.h

@@ -235,6 +235,8 @@ private slots:
 	void showLayoutsDialog();
 	void showUserInfoDialog(int userId);
 
+	void showAlterSelectionDialog();
+	void alterSelection(int expand, int feather, bool fromEdge);
 	void changeUndoDepthLimit();
 
 	void updateDevToolsActions();

src/libclient/CMakeLists.txt

@@ -195,6 +195,8 @@ target_sources(dpclient PRIVATE
 	utils/listservermodel.h
 	utils/logging.cpp
 	utils/logging.h
+	utils/selectionalteration.cpp
+	utils/selectionalteration.h
 	utils/selectionoutlinegenerator.cpp
 	utils/selectionoutlinegenerator.h
 	utils/sessionfilterproxymodel.cpp

src/libclient/document.cpp

@@ -1045,6 +1045,17 @@ void Document::selectLayerContents()
 	selectLayer(true);
 }
 
+void Document::selectMask(const QImage &img, int x, int y)
+{
+	if(img.isNull()) {
+		selectNone();
+	} else {
+		selectOp(
+			DP_MSG_SELECTION_PUT_OP_REPLACE,
+			QRect(x, y, img.width(), img.height()), img);
+	}
+}
+
 void Document::selectLayer(bool includeMask)
 {
 	if(m_canvas) {

src/libclient/document.h

@@ -270,6 +270,7 @@ public slots:
 	void selectInvert();
 	void selectLayerBounds();
 	void selectLayerContents();
+	void selectMask(const QImage &img, int x, int y);
 
 	void copyVisible();
 	void copyMerged();