Allow scaling animation exports

By entering a percentage scale and picking whether you want it bilinear
or nearest-neighbor.

ChangeLog

@@ -1,5 +1,6 @@
 Unreleased Version 2.2.2-pre
  * Fix: Solve rendering glitches with selection outlines that happen on some systems. Thanks xxxx for reporting.
+ * Feature: Allow scaling animation exports. Thanks Hopfel for animating across a giant canvas.
 
 2024-08-09 Version 2.2.2-beta.3
  * Fix: Use more accurate timers for performance profiles if the platform supports it.

src/desktop/dialogs/animationexportdialog.cpp

@@ -6,6 +6,7 @@
 #include "libclient/canvas/documentmetadata.h"
 #include "libclient/canvas/paintengine.h"
 #include "libclient/export/animationformat.h"
+#include <QCheckBox>
 #include <QComboBox>
 #include <QDialogButtonBox>
 #include <QFormLayout>
@@ -21,7 +22,8 @@
 
 namespace dialogs {
 
-AnimationExportDialog::AnimationExportDialog(QWidget *parent)
+AnimationExportDialog::AnimationExportDialog(
+	int scalePercent, bool scaleSmooth, QWidget *parent)
 	: QDialog(parent)
 {
 	setWindowTitle(tr("Export Animation"));
@@ -62,6 +64,22 @@ AnimationExportDialog::AnimationExportDialog(QWidget *parent)
 	m_loopsSpinner->setRange(1, 99);
 	outputForm->addRow(m_loopsLabel, m_loopsSpinner);
 
+	m_scaleSpinner = new QSpinBox;
+	m_scaleSpinner->setRange(1, 1000);
+	m_scaleSpinner->setValue(scalePercent);
+	m_scaleSpinner->setSuffix(tr("%"));
+
+	m_scaleSmoothBox = new QCheckBox(tr("Smooth"));
+	m_scaleSmoothBox->setChecked(scaleSmooth);
+
+	QHBoxLayout *scaleLayout = new QHBoxLayout;
+	scaleLayout->addWidget(m_scaleSpinner);
+	scaleLayout->addWidget(m_scaleSmoothBox);
+	outputForm->addRow(tr("Scale:"), scaleLayout);
+
+	m_scaleLabel = new QLabel;
+	outputForm->addRow(m_scaleLabel);
+
 	QWidget *inputWidget = new QWidget;
 	QFormLayout *inputForm = new QFormLayout(inputWidget);
 	tabs->addTab(inputWidget, tr("Input"));
@@ -128,6 +146,9 @@ AnimationExportDialog::AnimationExportDialog(QWidget *parent)
 	connect(
 		m_formatCombo, QOverload<int>::of(&QComboBox::currentIndexChanged),
 		this, &AnimationExportDialog::updateOutputUi);
+	connect(
+		m_scaleSpinner, QOverload<int>::of(&QSpinBox::valueChanged), this,
+		&AnimationExportDialog::updateScalingUi);
 	connect(
 		m_startSpinner, QOverload<int>::of(&QSpinBox::valueChanged), this,
 		&AnimationExportDialog::updateEndRange);
@@ -137,15 +158,27 @@ AnimationExportDialog::AnimationExportDialog(QWidget *parent)
 	connect(
 		m_x1Spinner, QOverload<int>::of(&QSpinBox::valueChanged), this,
 		&AnimationExportDialog::updateX2Range);
+	connect(
+		m_x1Spinner, QOverload<int>::of(&QSpinBox::valueChanged), this,
+		&AnimationExportDialog::updateScalingUi);
 	connect(
 		m_x2Spinner, QOverload<int>::of(&QSpinBox::valueChanged), this,
 		&AnimationExportDialog::updateX1Range);
+	connect(
+		m_x2Spinner, QOverload<int>::of(&QSpinBox::valueChanged), this,
+		&AnimationExportDialog::updateScalingUi);
 	connect(
 		m_y1Spinner, QOverload<int>::of(&QSpinBox::valueChanged), this,
 		&AnimationExportDialog::updateY2Range);
+	connect(
+		m_y1Spinner, QOverload<int>::of(&QSpinBox::valueChanged), this,
+		&AnimationExportDialog::updateScalingUi);
 	connect(
 		m_y2Spinner, QOverload<int>::of(&QSpinBox::valueChanged), this,
 		&AnimationExportDialog::updateY1Range);
+	connect(
+		m_y2Spinner, QOverload<int>::of(&QSpinBox::valueChanged), this,
+		&AnimationExportDialog::updateScalingUi);
 	connect(
 		m_inputResetButton, &QPushButton::clicked, this,
 		&AnimationExportDialog::resetInputs);
@@ -163,6 +196,7 @@ AnimationExportDialog::AnimationExportDialog(QWidget *parent)
 		&AnimationExportDialog::requestExport, Qt::DirectConnection);
 
 	updateOutputUi();
+	updateScalingUi();
 }
 
 void AnimationExportDialog::setCanvas(canvas::CanvasModel *canvas)
@@ -201,6 +235,13 @@ void AnimationExportDialog::setFlipbookState(
 	}
 }
 
+QSize AnimationExportDialog::getScaledSizeFor(
+	int scalePercent, const QRect &rect)
+{
+	QSize size = rect.size() * (scalePercent / 100.0);
+	return QSize(qMax(size.width(), 1), qMax(size.height(), 1));
+}
+
 #ifndef __EMSCRIPTEN__
 void AnimationExportDialog::accept()
 {
@@ -220,6 +261,16 @@ void AnimationExportDialog::updateOutputUi()
 	m_loopsSpinner->setVisible(showLoops);
 }
 
+void AnimationExportDialog::updateScalingUi()
+{
+	int scalePercent = m_scaleSpinner->value();
+	m_scaleSmoothBox->setEnabled(scalePercent != 100);
+	QSize size = getScaledSizeFor(scalePercent, getCropRect());
+	m_scaleLabel->setText(tr("Output resolution will be %1x%2 pixels.")
+							  .arg(size.width())
+							  .arg(size.height()));
+}
+
 #ifndef __EMSCRIPTEN__
 QString AnimationExportDialog::choosePath()
 {
@@ -340,6 +391,7 @@ void AnimationExportDialog::setCanvasSize(const QSize &size)
 	}
 	m_canvasWidth = size.width();
 	m_canvasHeight = size.height();
+	updateScalingUi();
 }
 
 void AnimationExportDialog::setCanvasFrameCount(int frameCount)
@@ -376,10 +428,15 @@ void AnimationExportDialog::requestExport()
 		m_path,
 #endif
 		format, m_loopsSpinner->value(), m_startSpinner->value() - 1,
-		m_endSpinner->value() - 1, m_framerateSpinner->value(),
-		QRect(
-			QPoint(m_x1Spinner->value(), m_y1Spinner->value()),
-			QPoint(m_x2Spinner->value(), m_y2Spinner->value())));
+		m_endSpinner->value() - 1, m_framerateSpinner->value(), getCropRect(),
+		m_scaleSpinner->value(), m_scaleSmoothBox->isChecked());
+}
+
+QRect AnimationExportDialog::getCropRect() const
+{
+	return QRect(
+		QPoint(m_x1Spinner->value(), m_y1Spinner->value()),
+		QPoint(m_x2Spinner->value(), m_y2Spinner->value()));
 }
 
 }

src/desktop/dialogs/animationexportdialog.h

@@ -4,6 +4,8 @@
 #include <QDialog>
 #include <QHash>
 
+class KisSliderSpinBox;
+class QCheckBox;
 class QComboBox;
 class QDialogButtonBox;
 class QLabel;
@@ -20,14 +22,17 @@ namespace dialogs {
 class AnimationExportDialog final : public QDialog {
 	Q_OBJECT
 public:
-	explicit AnimationExportDialog(QWidget *parent = nullptr);
+	explicit AnimationExportDialog(
+		int scalePercent, bool scaleSmooth, QWidget *parent = nullptr);
 
 	void setCanvas(canvas::CanvasModel *canvas);
 
 	void setFlipbookState(
 		int start, int end, double speedPercent, const QRectF &crop,
 		bool apply);
 
+	static QSize getScaledSizeFor(int scalePercent, const QRect &rect);
+
 public slots:
 #ifndef __EMSCRIPTEN__
 	void accept() override;
@@ -39,10 +44,11 @@ public slots:
 		const QString &path,
 #endif
 		int format, int loops, int start, int end, int framerate,
-		const QRect &crop);
+		const QRect &crop, int scalePercent, bool scaleSmooth);
 
 private:
 	void updateOutputUi();
+	void updateScalingUi();
 #ifndef __EMSCRIPTEN__
 	QString choosePath();
 #endif
@@ -62,11 +68,16 @@ public slots:
 
 	void requestExport();
 
+	QRect getCropRect() const;
+
 #ifndef __EMSCRIPTEN__
 	QString m_path;
 #endif
 	QComboBox *m_formatCombo;
 	QLabel *m_loopsLabel;
+	QSpinBox *m_scaleSpinner;
+	QCheckBox *m_scaleSmoothBox;
+	QLabel *m_scaleLabel;
 	QSpinBox *m_loopsSpinner;
 	QSpinBox *m_startSpinner;
 	QSpinBox *m_endSpinner;

src/desktop/mainwindow.cpp

@@ -1927,7 +1927,8 @@ void MainWindow::showAnimationExportDialog(bool fromFlipbook)
 		dlg->activateWindow();
 		dlg->raise();
 	} else {
-		dlg = new dialogs::AnimationExportDialog(this);
+		dlg = new dialogs::AnimationExportDialog(
+			m_animationExportScalePercent, m_animationExportScaleSmooth, this);
 		dlg->setAttribute(Qt::WA_DeleteOnClose);
 		dlg->setObjectName(objectName);
 		dlg->setCanvas(m_doc->canvas());
@@ -1958,19 +1959,33 @@ void MainWindow::exportAnimation(
 #ifndef __EMSCRIPTEN__
 	const QString &path,
 #endif
-	int format, int loops, int start, int end, int framerate, const QRect &crop)
+	int format, int loops, int start, int end, int framerate, const QRect &crop,
+	int scalePercent, bool scaleSmooth)
 {
+	m_animationExportScalePercent = scalePercent;
+	m_animationExportScaleSmooth = scaleSmooth;
+
 	QProgressDialog *progressDialog = new QProgressDialog(
 		tr("Saving animation..."), tr("Cancel"), 0, 100, this);
 	progressDialog->setMinimumDuration(500);
 	progressDialog->setValue(0);
 
+	drawdance::CanvasState canvasState =
+		m_doc->canvas()->paintEngine()->viewCanvasState();
+	QRect canvasRect = QRect(QPoint(0, 0), canvasState.size());
+	QRect effectiveCrop = crop & canvasRect;
+	if(effectiveCrop.isEmpty()) {
+		effectiveCrop = canvasRect;
+	}
+	QSize size = dialogs::AnimationExportDialog::getScaledSizeFor(
+		scalePercent, effectiveCrop);
+
 	AnimationSaverRunnable *saver = new AnimationSaverRunnable(
 #ifndef __EMSCRIPTEN__
 		path,
 #endif
-		format, loops, start, end, framerate, crop,
-		m_doc->canvas()->paintEngine()->viewCanvasState(), this);
+		format, size.width(), size.height(), loops, start, end, framerate,
+		effectiveCrop, scaleSmooth, canvasState, this);
 	saver->setAutoDelete(true);
 
 	connect(

src/desktop/mainwindow.h

@@ -298,7 +298,7 @@ private slots:
 		const QString &path,
 #endif
 		int format, int loops, int start, int end, int framerate,
-		const QRect &crop);
+		const QRect &crop, int scalePercent, bool scaleSmooth);
 
 	ActionBuilder makeAction(const char *name, const QString &text = QString{});
 	QAction *getAction(const QString &name);
@@ -404,6 +404,8 @@ private slots:
 	dialogs::SessionSettingsDialog *m_sessionSettings;
 	dialogs::ServerLogDialog *m_serverLogDialog;
 	dialogs::Flipbook::State m_flipbookState;
+	int m_animationExportScalePercent = 100;
+	bool m_animationExportScaleSmooth = true;
 
 #ifndef __EMSCRIPTEN__
 	QMenu *m_recentMenu;

src/drawdance/libengine/dpengine/image.c

@@ -424,6 +424,34 @@ bool DP_image_thumbnail(DP_Image *img, DP_DrawContext *dc, int max_width,
     }
 }
 
+DP_Image *DP_image_scale(DP_Image *img, DP_DrawContext *dc, int width,
+                         int height, int interpolation)
+{
+    DP_ASSERT(img);
+    DP_ASSERT(dc);
+    if (width > 0 && height > 0) {
+        int src_width = DP_image_width(img);
+        int src_height = DP_image_height(img);
+        DP_Transform tf = DP_transform_scale(
+            DP_transform_identity(),
+            DP_int_to_double(width) / DP_int_to_double(src_width),
+            DP_int_to_double(height) / DP_int_to_double(src_height));
+        DP_Image *result = DP_image_new(width, height);
+        if (DP_image_transform_draw(src_width, src_height, DP_image_pixels(img),
+                                    dc, result, tf, interpolation)) {
+            return result;
+        }
+        else {
+            DP_image_free(result);
+            return NULL;
+        }
+    }
+    else {
+        DP_error_set("Can't scale to zero dimensions");
+        return NULL;
+    }
+}
+
 bool DP_image_same_pixel(DP_Image *img, DP_Pixel8 *out_pixel)
 {
     DP_Pixel8 *pixels = DP_image_pixels(img);

src/drawdance/libengine/dpengine/image.h

@@ -97,6 +97,9 @@ DP_Image *DP_image_transform(DP_Image *img, DP_DrawContext *dc,
 bool DP_image_thumbnail(DP_Image *img, DP_DrawContext *dc, int max_width,
                         int max_height, DP_Image **out_thumb) DP_MUST_CHECK;
 
+DP_Image *DP_image_scale(DP_Image *img, DP_DrawContext *dc, int width,
+                         int height, int interpolation);
+
 bool DP_image_same_pixel(DP_Image *img, DP_Pixel8 *out_pixel);
 
 DP_UPixelFloat DP_image_sample_color_at_with(int width, int height,