feat: drawing popout now clips strokes again + add redo + add undo and redo keybinds

Plugins/ZShell/Internal/strokecanvasrenderer.cpp

@@ -1,11 +1,98 @@
 #include "strokecanvasrenderer.hpp"
 #include "strokecanvasitem.hpp"
+#include <QCanvasPainter>
+#include <QQuickWindow>
+#include <QVector4D>
 #include <qcolor.h>
 #include <QSet>
 
 namespace ZShell::internal {
 
-static void drawStroke(
+using Qt::StringLiterals::operator""_s;
+
+static const QString kStrokeHoleShader = u":/shaders/strokeholemask.frag.qsb"_s;
+
+namespace {
+
+struct HoleUniforms {
+	QVector4D data1; // center.xy, halfSize.xy
+	QVector4D data3; // x: radius, y: feather in logical px
+	QVector4D data4; // x: hole enabled
+};
+
+static HoleUniforms holeUniforms(
+	const QRectF& hole, qreal radius, qreal devicePixelRatio) {
+	const bool active = hole.isValid() && hole.width() > 0 && hole.height() > 0;
+
+	if (!active) return {QVector4D(), QVector4D(), QVector4D()};
+
+	const QPointF center = hole.center();
+	const QPointF half(hole.width() * 0.5, hole.height() * 0.5);
+	const qreal maxRadius = qMin(half.x(), half.y());
+
+	return {
+		QVector4D(
+			static_cast<float>(center.x()),
+			static_cast<float>(center.y()),
+			static_cast<float>(half.x()),
+			static_cast<float>(half.y())),
+		QVector4D(
+			static_cast<float>(qMin(radius, maxRadius)),
+			static_cast<float>(1.0 / devicePixelRatio),
+			0.0f,
+			0.0f),
+		QVector4D(1.0, 0.0, 0.0, 0.0),
+	};
+}
+
+static void applyHole(QCanvasCustomBrush& brush, const HoleUniforms& u) {
+	brush.setData1(u.data1);
+	brush.setData3(u.data3);
+	brush.setData4(u.data4);
+}
+
+}; // namespace
+
+void StrokeCanvasRenderer::updateBrushHole() {
+	const HoleUniforms uniforms =
+		holeUniforms(m_hole, m_holeRadius, m_devicePixelRatio);
+
+	if (uniforms.data1 == m_lastHoleData1 &&
+		uniforms.data3 == m_lastHoleData3 && uniforms.data4 == m_lastHoleData4)
+		return;
+
+	m_lastHoleData1 = uniforms.data1;
+	m_lastHoleData3 = uniforms.data3;
+	m_lastHoleData4 = uniforms.data4;
+	++m_holeToken;
+
+	for (auto& entry : m_brushes) {
+		if (entry.holeToken == m_holeToken) continue;
+
+		applyHole(entry.brush, uniforms);
+		entry.holeToken = m_holeToken;
+	}
+}
+
+QCanvasCustomBrush& StrokeCanvasRenderer::brushFor(const QColor& color) {
+	const QRgb key = color.rgba();
+
+	if (auto it = m_brushes.find(key); it != m_brushes.end()) return it->brush;
+
+	const HoleUniforms uniforms =
+		holeUniforms(m_hole, m_holeRadius, m_devicePixelRatio);
+
+	BrushEntry entry;
+	entry.brush.setFragmentShader(kStrokeHoleShader);
+	applyHole(entry.brush, uniforms);
+	entry.brush.setData2(
+		QVector4D(color.redF(), color.greenF(), color.blueF(), color.alphaF()));
+	entry.holeToken = m_holeToken;
+
+	return m_brushes.insert(key, entry)->brush;
+}
+
+void StrokeCanvasRenderer::drawStroke(
 	QCanvasPainter* painter,
 	const QVector<QPointF>& points,
 	const QColor& color,
@@ -13,8 +100,10 @@ static void drawStroke(
 	bool polyline) {
 	if (points.isEmpty()) return;
 
-	painter->setStrokeStyle(color);
-	painter->setFillStyle(color);
+	QCanvasCustomBrush& brush = brushFor(color);
+
+	painter->setStrokeStyle(brush);
+	painter->setFillStyle(brush);
 	painter->setLineWidth(width);
 	painter->setLineCap(QCanvasPainter::LineCap::Round);
 	painter->setLineJoin(QCanvasPainter::LineJoin::Round);
@@ -65,7 +154,7 @@ static void drawStroke(
 	painter->stroke();
 }
 
-static void drawHoverCursor(
+void StrokeCanvasRenderer::drawHoverCursor(
 	QCanvasPainter* painter,
 	const QPointF& point,
 	qreal penWidth,
@@ -74,7 +163,7 @@ static void drawHoverCursor(
 	const qreal radius = penWidth * 0.5;
 
 	if (isDrawing) {
-		painter->setFillStyle(penColor);
+		painter->setFillStyle(brushFor(penColor));
 		painter->beginPath();
 		painter->circle(point, radius);
 		painter->fill();
@@ -85,7 +174,7 @@ static void drawHoverCursor(
 	const bool useDashes = penWidth > 10.0;
 
 	auto drawOutline = [&](const QColor& color, qreal width) {
-		painter->setStrokeStyle(color);
+		painter->setStrokeStyle(brushFor(color));
 		painter->setLineWidth(width);
 		painter->setLineCap(QCanvasPainter::LineCap::Round);
 
@@ -117,7 +206,7 @@ static void drawHoverCursor(
 	};
 
 	auto drawCrosshair = [&](const QColor& color, qreal width) {
-		painter->setStrokeStyle(color);
+		painter->setStrokeStyle(brushFor(color));
 		painter->setLineWidth(width);
 		painter->setLineCap(QCanvasPainter::LineCap::Round);
 
@@ -148,8 +237,11 @@ void StrokeCanvasRenderer::synchronizeData(QCanvasPainterItem* item) {
 
 	m_penColor = canvas->m_penColor;
 	m_penWidth = canvas->m_penWidth;
+	m_hole = canvas->m_hole;
+	m_holeRadius = canvas->m_holeRadius;
+	m_devicePixelRatio =
+		canvas->window() ? canvas->window()->effectiveDevicePixelRatio() : 1.0;
 
-	// Detect removed strokes: present in renderer but no longer in canvas
 	QSet<int> canvasGroupIds;
 	for (const auto& stroke : canvas->m_strokes)
 		canvasGroupIds.insert(stroke.groupId);
@@ -162,7 +254,6 @@ void StrokeCanvasRenderer::synchronizeData(QCanvasPainterItem* item) {
 		}
 	}
 
-	// Detect added strokes: present in canvas but not yet in renderer
 	QSet<int> rendererGroupIds;
 	for (const auto& stroke : m_strokes)
 		rendererGroupIds.insert(stroke.groupId);
@@ -180,6 +271,8 @@ void StrokeCanvasRenderer::synchronizeData(QCanvasPainterItem* item) {
 }
 
 void StrokeCanvasRenderer::paint(QCanvasPainter* painter) {
+	updateBrushHole();
+
 	for (int id : m_pendingGroupRemovals)
 		painter->removePathGroup(id);
 	m_pendingGroupRemovals.clear();
@@ -187,8 +280,8 @@ void StrokeCanvasRenderer::paint(QCanvasPainter* painter) {
 	painter->clearRect(0, 0, width(), height());
 
 	for (const auto& stroke : m_strokes) {
-		painter->setStrokeStyle(stroke.color);
-		painter->setFillStyle(stroke.color);
+		painter->setStrokeStyle(brushFor(stroke.color));
+		painter->setFillStyle(brushFor(stroke.color));
 		painter->setLineWidth(stroke.width);
 		painter->setLineCap(QCanvasPainter::LineCap::Round);
 		painter->setLineJoin(QCanvasPainter::LineJoin::Round);