Unify the code samples to use QImage

The API should be backward compatible but the overzoom extension should rather
be promoted with a major version number change.

.appveyor.yml

@@ -0,0 +1,32 @@
+version: 3.0.{build}
+
+configuration:
+  - Release
+
+image:
+  - Visual Studio 2022
+
+environment:
+  VCPKGDIR: C:\tools\vcpkg\installed\x64-windows-static-md
+  matrix:
+  - QTDIR: C:\Qt\5.15\msvc2019_64
+  - QTDIR: C:\Qt\6.5\msvc2019_64
+
+install:
+- cmd: |-
+    set PATH=%QTDIR%\bin;%VCPKGDIR%\tools\protobuf;%PATH%
+    call "C:\Program Files\Microsoft Visual Studio\2022\Community\VC\Auxiliary\Build\vcvars64.bat
+    vcpkg install protobuf:x64-windows-static-md
+    vcpkg install zlib:x64-windows-static-md
+    copy /y %VCPKGDIR%\lib\zlib.lib %VCPKGDIR%\lib\zlibstatic.lib
+
+build_script:
+- cmd: |-
+    qmake PROTOBUF=%VCPKGDIR% ZLIB=%VCPKGDIR% pbfplugin.pro
+    nmake release
+
+artifacts:
+- path: release\pbf3.dll
+
+cache:
+- C:\tools\vcpkg\installed\

.github/workflows/linux.yml

@@ -11,7 +11,7 @@ jobs:
     runs-on: ubuntu-20.04
     steps:
       - name: Checkout
-        uses: actions/checkout@v2
+        uses: actions/checkout@v3
       - name: Install dependencies
         run: |
           sudo apt-get update

.github/workflows/osx.yml

@@ -6,17 +6,32 @@ on:
       - master
 
 jobs:
-  build:
+  qt5:
-    name: QtPBFImagePlugin
+    name: QtPBFImagePlugin Qt5 build
-    runs-on: macos-10.15
+    runs-on: macos-latest
     steps:
       - name: Set environment variables
-        run: echo "PATH=/usr/local/opt/qt@5/bin:$PATH" >> $GITHUB_ENV
+        run: echo "PATH=/usr/local/opt/qt@5/bin:/usr/local/opt/protobuf@21/bin:$PATH" >> $GITHUB_ENV
       - name: Checkout
-        uses: actions/checkout@v2
+        uses: actions/checkout@v3
       - name: Install dependencies
-        run: brew install qt5 protobuf
+        run: brew install qt@5 protobuf@21
       - name: Configure build
-        run: qmake PROTOBUF=/usr/local pbfplugin.pro
+        run: qmake PROTOBUF=/usr/local/opt/protobuf@21 pbfplugin.pro
+      - name: Build project
+        run: make -j3
+
+  qt6:
+    name: QtPBFImagePlugin Qt6 build
+    runs-on: macos-latest
+    steps:
+      - name: Set environment variables
+        run: echo "PATH=/usr/local/opt/qt@6/bin:/usr/local/opt/protobuf@21/bin:$PATH" >> $GITHUB_ENV
+      - name: Checkout
+        uses: actions/checkout@v3
+      - name: Install dependencies
+        run: brew install qt@6 protobuf@21
+      - name: Configure build
+        run: qmake PROTOBUF=/usr/local/opt/protobuf@21 pbfplugin.pro
       - name: Build project
         run: make -j3

README.md

@@ -18,24 +18,39 @@ to fit the styles and available data (OpenMapTiles, Mapbox tiles).
 Due to a major design flaw in the Mapbox vector tiles specification - the zoom
 is not part of the PBF data - the plugin can not be used "as is", but passing
 the zoom level is necessary. This is done by exploiting the optional *format*
-parameter of the QImage constructor or the QImage::fromData() or
+parameter of the QImage constructor or the *QImage::loadFromData()* or
-QPixmap::loadFromData() functions. The zoom number is passed as ASCII string
+*QPixmap::loadFromData()* functions. The zoom number is passed as ASCII string
 to the functions:
 ```cpp
-QPixmap pm;
+QImage img;
-pm.loadFromData(tileData, QString::number(zoom).toLatin1());
+img.loadFromData(data, QByteArray::number(zoom));
 ```
-The plugin supports vector scaling using QImageReader's setScaledSize() method,
+
+For a complete code sample see the [pbf2png](https://github.com/tumic0/pbf2png)
+conversion utility.
+
+### HiDPI
+The plugin supports vector scaling using QImageReader's *setScaledSize()* method,
 so when used like in the following example:
 ```cpp
-QImageReader reader(file, QString::number(zoom).toLatin1());
+QImage img;
+QImageReader reader(file, QByteArray::number(zoom));
 reader.setScaledSize(QSize(1024, 1024));
-reader.read(&image);
+reader.read(&img);
 ```
 you will get 1024x1024px tiles with a pixel ratio of 2 (= HiDPI tiles).
 
-For a sample code see the [pbf2png](https://github.com/tumic0/pbf2png)
+### Overzoom
-conversion utility.
+Since version 3 of the plugin tile overzoom is supported. If you set *format*
+to `$zoom;$overzoom`:
+```cpp
+QImage img;
+QByteArray fmt(QByteArray::number(zoom) + ';' + QByteArray::number(overzoom));
+img.loadFromData(data, fmt);
+```
+you will get (512<<overzoom)x(512<<overzoom)px tiles with a pixel ratio of 1.
+When overzoom is combined with setScaledSize(), the base size is the overzoomed
+tile size.
 
 ## Styles
 The map style is loaded from the

pbfplugin.pro

@@ -2,6 +2,7 @@ TARGET  = pbf
 TEMPLATE = lib
 CONFIG += plugin
 QT += gui
+VERSION = 3.0
 
 PROTOS = protobuf/vector_tile.proto
 include(protobuf/vector_tile.pri)
@@ -47,6 +48,10 @@ win32 {
         $$ZLIB/include
     LIBS += $$PROTOBUF/lib/libprotobuf-lite.lib \
         $$ZLIB/lib/zlibstatic.lib
+
+    QMAKE_TARGET_PRODUCT = QtPBFImagePlugin
+    QMAKE_TARGET_DESCRIPTION = Qt $$QT_VERSION MVT/PBF image plugin
+    QMAKE_TARGET_COPYRIGHT = Copyright (c) 2023 Martin Tuma
 }
 macx {
     INCLUDEPATH += $$PROTOBUF/include

src/gzip.cpp

@@ -6,7 +6,7 @@
 
 QByteArray Gzip::uncompress(QIODevice *device, int limit)
 {
-	int ret;
+	int ret = Z_STREAM_END;
 	z_stream strm;
 	unsigned char in[CHUNK];
 	unsigned char out[CHUNK];

src/pbfhandler.cpp

@@ -79,16 +79,19 @@ bool PBFHandler::read(QImage *image)
 		return false;
 	}
 
-	bool ok;
+	QList<QByteArray> list(format().split(';'));
-	int zoom = format().toInt(&ok);
+	int zoom = list.size() ? list.first().toInt() : 0;
+	int overzoom = (list.size() > 1) ? list.at(1).toInt() : 0;
+
+	QSize scaledSize(_scaledSize.isValid()
+	  ? _scaledSize : QSize(TILE_SIZE, TILE_SIZE));
+	QSize size(scaledSize.width()<<overzoom,
+	  scaledSize.height()<<overzoom);
+	QPointF scale((qreal)scaledSize.width() / TILE_SIZE,
+	  (qreal)scaledSize.height() / TILE_SIZE);
 
-	QSize size = _scaledSize.isValid()
-	  ? _scaledSize : QSize(TILE_SIZE, TILE_SIZE);
-	QPointF scale = _scaledSize.isValid()
-	  ? QPointF((qreal)_scaledSize.width() / TILE_SIZE,
-		(qreal)_scaledSize.height() / TILE_SIZE) : QPointF(1.0, 1.0);
 	*image = QImage(size, QImage::Format_ARGB32_Premultiplied);
-	Tile tile(image, ok ? zoom : -1, scale);
+	Tile tile(image, zoom, scale);
 
 	_style->render(data, tile);
 

src/textitem.cpp

@@ -21,14 +21,14 @@ qreal TextItem::avgCharWidth() const
 		ratio = 1.0;
 	// Greek & Cyrilic
 	else if (cp >= 0x03FF && cp <= 0x04FF) {
-		ratio = (_font.capitalization() == QFont::AllUppercase) ? 0.80 : 0.73;
+		ratio = (_font.capitalization() == QFont::AllUppercase) ? 0.80 : 0.70;
 		if (_font.bold())
 			ratio *= 1.1;
 		if (_font.italic())
 			ratio *= 0.9;
 	// The rest (Latin scripts, Arabic, ...)
 	} else {
-		ratio = (_font.capitalization() == QFont::AllUppercase) ? 0.75 : 0.63;
+		ratio = (_font.capitalization() == QFont::AllUppercase) ? 0.75 : 0.60;
 		if (_font.bold())
 			ratio *= 1.1;
 		if (_font.italic())

src/textpathitem.cpp

@@ -9,23 +9,20 @@
 #define INTERSECTS intersects
 #endif // QT 5.15
 
-static bool intersection(const QLineF &line, const QRectF &rect,
+static void swap(const QLineF &line, QPointF *p1, QPointF *p2)
-  QPointF *p)
 {
-	if (line.INTERSECTS(QLineF(rect.topLeft(), rect.topRight()), p)
-	  == QLineF::BoundedIntersection)
-		return true;
-	if (line.INTERSECTS(QLineF(rect.topLeft(), rect.bottomLeft()), p)
-	  == QLineF::BoundedIntersection)
-		return true;
-	if (line.INTERSECTS(QLineF(rect.bottomRight(), rect.bottomLeft()), p)
-	  == QLineF::BoundedIntersection)
-		return true;
-	if (line.INTERSECTS(QLineF(rect.bottomRight(), rect.topRight()), p)
-	  == QLineF::BoundedIntersection)
-		return true;
 
-	return false;
+	QPointF lp1(line.p1());
+	QPointF lp2(line.p2());
+
+	if ((lp1.rx() < lp2.rx() && p1->rx() > p2->rx())
+	  || (lp1.ry() < lp2.ry() && p1->ry() > p2->ry())
+	  || (lp1.rx() > lp2.rx() && p1->rx() < p2->rx())
+	  || (lp1.ry() > lp2.ry() && p1->ry() < p2->ry())) {
+		QPointF tmp(*p2);
+		*p2 = *p1;
+		*p1 = tmp;
+	}
 }
 
 static bool intersection(const QLineF &line, const QRectF &rect, QPointF *p1,
@@ -38,20 +35,26 @@ static bool intersection(const QLineF &line, const QRectF &rect, QPointF *p1,
 		p = p2;
 	if (line.INTERSECTS(QLineF(rect.topLeft(), rect.bottomLeft()), p)
 	  == QLineF::BoundedIntersection) {
-		if (p == p2)
+		if (p == p2) {
+			swap(line, p1, p2);
 			return true;
+		}
 		p = p2;
 	}
 	if (line.INTERSECTS(QLineF(rect.bottomRight(), rect.bottomLeft()), p)
 	  == QLineF::BoundedIntersection) {
-		if (p == p2)
+		if (p == p2) {
+			swap(line, p1, p2);
 			return true;
+		}
 		p = p2;
 	}
 	if (line.INTERSECTS(QLineF(rect.bottomRight(), rect.topRight()), p)
 	  == QLineF::BoundedIntersection) {
-		if (p == p2)
+		if (p == p2) {
+			swap(line, p1, p2);
 			return true;
+		}
 	}
 
 	Q_ASSERT(p != p2);
@@ -59,22 +62,42 @@ static bool intersection(const QLineF &line, const QRectF &rect, QPointF *p1,
 	return false;
 }
 
-static QPainterPath subpath(const QList<QLineF> &lines, int start, int end,
+static bool intersection(const QLineF &line, const QRectF &rect, QPointF *p)
+{
+	if (line.INTERSECTS(QLineF(rect.topLeft(), rect.topRight()), p)
+	  == QLineF::BoundedIntersection)
+		return true;
+	if (line.INTERSECTS(QLineF(rect.topLeft(), rect.bottomLeft()), p)
+	  == QLineF::BoundedIntersection)
+		return true;
+	if (line.INTERSECTS(QLineF(rect.bottomRight(), rect.bottomLeft()), p)
+	  == QLineF::BoundedIntersection)
+		return true;
+	if (line.INTERSECTS(QLineF(rect.bottomRight(), rect.topRight()), p)
+	  == QLineF::BoundedIntersection)
+		return true;
+
+	return false;
+}
+
+static QPainterPath subpath(const QPolygonF &path, int start, int end,
   qreal cut)
 {
 	qreal ss = 0, es = 0;
 	int si = start, ei = end;
 
-	for (int i = start; i <= end; i++) {
+	for (int i = start; i < end; i++) {
-		qreal len = lines.at(i).length();
+		QLineF l(path.at(i), path.at(i+1));
+		qreal len = l.length();
 		if (ss + len < cut / 2) {
 			ss += len;
 			si++;
 		} else
 			break;
 	}
-	for (int i = end; i >= start; i--) {
+	for (int i = end; i > start; i--) {
-		qreal len = lines.at(i).length();
+		QLineF l(path.at(i), path.at(i-1));
+		qreal len = l.length();
 		if (es + len < cut / 2) {
 			es += len;
 			ei--;
@@ -82,98 +105,117 @@ static QPainterPath subpath(const QList<QLineF> &lines, int start, int end,
 			break;
 	}
 
-	QLineF sl(lines.at(si).p2(), lines.at(si).p1());
+	QLineF sl(path.at(si+1), path.at(si));
 	sl.setLength(sl.length() - (cut / 2 - ss));
-	QLineF el(lines.at(ei));
+	QLineF el(path.at(ei-1), path.at(ei));
 	el.setLength(el.length() - (cut / 2 - es));
 
 	QPainterPath p(sl.p2());
-	for (int i = si; i <= ei; i++)
+	for (int i = si + 1; i < ei; i++)
-		p.lineTo(lines.at(i).p2());
+		p.lineTo(path.at(i));
-	p.setElementPositionAt(p.elementCount() - 1, el.p2().x(), el.p2().y());
+	p.lineTo(el.p2());
 
 	return p;
 }
 
-static QList<QLineF> lineString(const QPainterPath &path,
+static QList<QPolygonF> polyLines(const QPainterPath &path, const QRectF &rect)
-  const QRectF &boundingRect)
 {
-	QList<QLineF> lines;
+	QList<QPolygonF> lines;
-	int start = -1, end = -1;
+	QPolygonF line;
+	bool lastIn = rect.contains(path.elementAt(0));
 
+	for (int i = 1; i < path.elementCount(); i++) {
+		if (rect.contains(path.elementAt(i))) {
+			if (lastIn) {
+				if (line.isEmpty())
+					line.append(path.elementAt(i-1));
+				line.append(path.elementAt(i));
+			} else {
+				QPointF p;
+				QLineF l(path.elementAt(i-1), path.elementAt(i));
 
-	for (int i = 0; i < path.elementCount(); i++) {
+				if (intersection(l, rect, &p))
-		if (boundingRect.contains(path.elementAt(i))) {
+					line.append(p);
-			start = i;
+				line.append(path.elementAt(i));
-			break;
-		}
-	}
-	for (int i = path.elementCount() - 1; i >= 0; i--) {
-		if (boundingRect.contains(path.elementAt(i))) {
-			end = i;
-			break;
-		}
-	}
-
-	if (start < 0) {
-		QPointF p1, p2;
-
-		for (int i = 1; i < path.elementCount(); i++) {
-			QLineF l(path.elementAt(i-1), path.elementAt(i));
-			if (intersection(l, boundingRect, &p1, &p2)) {
-				lines.append(QLineF(p1, p2));
-				break;
 			}
-		}
-	} else {
-		QPointF p;
 
-		if (start > 0) {
+			lastIn = true;
-			QLineF l(path.elementAt(start-1), path.elementAt(start));
+		} else {
-			if (intersection(l, boundingRect, &p))
+			QLineF l(path.elementAt(i-1), path.elementAt(i));
-				lines.append(QLineF(p, path.elementAt(start)));
+
-		}
+			if (lastIn) {
-		for (int i = start + 1; i <= end; i++)
+				QPointF p;
-			lines.append(QLineF(path.elementAt(i-1), path.elementAt(i)));
+				if (line.isEmpty())
-		if (end < path.elementCount() - 1) {
+					line.append(path.elementAt(i-1));
-			QLineF l(path.elementAt(end), path.elementAt(end+1));
+				if (intersection(l, rect, &p))
-			if (intersection(l, boundingRect, &p))
+					line.append(p);
-				lines.append(QLineF(path.elementAt(end), p));
+				lines.append(line);
+				line.clear();
+			} else {
+				QPointF p1, p2;
+				if (intersection(l, rect, &p1, &p2)) {
+					line.append(p1);
+					line.append(p2);
+					lines.append(line);
+					line.clear();
+				}
+			}
+
+			lastIn = false;
 		}
 	}
 
+	if (!line.isEmpty())
+		lines.append(line);
+
 	return lines;
 }
 
+static qreal diff(qreal a1, qreal a2)
+{
+	qreal d = qAbs(a1 - a2);
+	return (d > 180) ? 360 - d : d;
+}
+
 static QPainterPath textPath(const QPainterPath &path, qreal textWidth,
   qreal maxAngle, qreal charWidth, const QRectF &tileRect)
 {
-	QList<QLineF> lines(lineString(path, tileRect));
+	if (path.isEmpty())
-	if (lines.isEmpty())
 		return QPainterPath();
-	qreal length = 0;
+
-	qreal angle = lines.first().angle();
+	QList<QPolygonF> lines(polyLines(path, tileRect));
-	int last = 0;
 
 	for (int i = 0; i < lines.size(); i++) {
-		qreal sl = lines.at(i).length();
+		const QPolygonF &pl = lines.at(i);
-		qreal a = lines.at(i).angle();
+		qreal angle = 0, length = 0;
+		int last = 0;
 
-		if (!tileRect.contains(lines.at(i).p2()) || sl < charWidth
+		for (int j = 1; j < pl.size(); j ++) {
-		  || qAbs(angle - a) > maxAngle) {
+			QLineF l(pl.at(j-1), pl.at(j));
-			if (length > textWidth)
+			qreal sl = l.length();
-				return subpath(lines, last, i - 1, length - textWidth);
+			qreal a = l.angle();
-			last = i;
-			length = 0;
-		} else
-			length += sl;
 
-		angle = a;
+			if (sl < charWidth) {
+				if (length > textWidth)
+					return subpath(pl, last, j - 1, length - textWidth);
+				last = j;
+				length = 0;
+			} else if (j > 1 && diff(angle, a) > maxAngle) {
+				if (length > textWidth)
+					return subpath(pl, last, j - 1, length - textWidth);
+				last = j - 1;
+				length = sl;
+			} else
+				length += sl;
+
+			angle = a;
+		}
+
+		if (length > textWidth)
+			return subpath(pl, last, pl.size() - 1, length - textWidth);
 	}
 
-	return (length > textWidth)
+	return QPainterPath();
-	  ? subpath(lines, last, lines.size() - 1, length - textWidth)
-	  : QPainterPath();
 }
 
 static bool reverse(const QPainterPath &path)
@@ -208,9 +250,6 @@ TextPathItem::TextPathItem(const QString &text, const QPainterPath &path,
 
 void TextPathItem::paint(QPainter *painter) const
 {
-	//painter->setPen(Qt::red);
-	//painter->drawPath(_shape);
-
 	QFontMetrics fm(font());
 	int textWidth = fm.boundingRect(text()).width();
 
@@ -259,4 +298,9 @@ void TextPathItem::paint(QPainter *painter) const
 		int width = fm.horizontalAdvance(text().at(i));
 		percent += ((qreal)width / (qreal)textWidth) * factor;
 	}
+
+	//painter->setBrush(Qt::NoBrush);
+	//painter->setPen(Qt::red);
+	//painter->setRenderHint(QPainter::Antialiasing, false);
+	//painter->drawPath(_shape);
 }

style/style.json

@@ -2265,7 +2265,6 @@
       "source": "openmaptiles",
       "source-layer": "building",
       "minzoom": 13,
-      "maxzoom": 14,
       "layout": {
         "visibility": "visible"
       },