Proprly initialize the tile with transparent background

Qt 5.11 works as well

.github/workflows/linux.yml

@@ -0,0 +1,22 @@
+name: Linux
+
+on:
+  push:
+    branches:
+      - master
+
+jobs:
+  build:
+    name: QtPBFImagePlugin
+    runs-on: ubuntu-20.04
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v2
+      - name: Install dependencies
+        run: |
+          sudo apt-get update
+          sudo apt-get install qtbase5-dev qtbase5-dev-tools qt5-qmake libprotobuf-dev protobuf-compiler zlib1g-dev
+      - name: Configure build
+        run: qmake pbfplugin.pro
+      - name: Build project
+        run: make -j2

.github/workflows/osx.yml

@@ -0,0 +1,22 @@
+name: OS X
+
+on:
+  push:
+    branches:
+      - master
+
+jobs:
+  build:
+    name: QtPBFImagePlugin
+    runs-on: macos-10.15
+    steps:
+      - name: Set environment variables
+        run: echo "PATH=/usr/local/opt/qt@5/bin:$PATH" >> $GITHUB_ENV
+      - name: Checkout
+        uses: actions/checkout@v2
+      - name: Install dependencies
+        run: brew install qt5 protobuf
+      - name: Configure build
+        run: qmake PROTOBUF=/usr/local pbfplugin.pro
+      - name: Build project
+        run: make -j3

.travis.yml

@@ -1,23 +0,0 @@
-language: c++
-dist: focal
-
-os:
-  - linux
-  - osx
-
-env:
-  - QT_SELECT=qt5
-
-before_install:
-  - if [[ "$TRAVIS_OS_NAME" == "linux" ]]; then sudo apt-get -qq update; fi
-  - if [[ "$TRAVIS_OS_NAME" == "osx" ]]; then brew update; fi
-
-install:
-  - if [[ "$TRAVIS_OS_NAME" == "osx" ]]; then brew install qt protobuf; fi
-  - if [[ "$TRAVIS_OS_NAME" == "linux" ]]; then sudo apt-get install qtbase5-dev qtbase5-dev-tools qt5-qmake libprotobuf-dev protobuf-compiler; fi
-
-script:
-  - if [[ "$TRAVIS_OS_NAME" == "osx" ]]; then PATH=/usr/local/opt/qt/bin/:${PATH}; fi
-  - if [[ "$TRAVIS_OS_NAME" == "osx" ]]; then qmake PROTOBUF=/usr/local pbfplugin.pro; fi
-  - if [[ "$TRAVIS_OS_NAME" == "linux" ]]; then qmake pbfplugin.pro; fi
-  - make

README.md

@@ -7,7 +7,7 @@ displaying raster MBTiles maps or raster XYZ online maps to also display
 PBF(MVT) vector tiles without (almost, see usage) any application modifications.
 
 Standard Mapbox GL Styles are used for styling the maps. Most relevant style
-features used by [Maputnik](http://editor.openmaptiles.org) are supported.
+features used by [Maputnik](https://maputnik.github.io/editor) are supported.
 A default fallback style (OSM-Liberty) for OpenMapTiles is part of the plugin.
 
 "Plain" PBF files as well as gzip compressed files (as used in MBTiles) are
@@ -43,7 +43,8 @@ The map style is loaded from the
 file on plugin load. If the style uses a sprite, the sprite JSON file must
 be named `sprite.json` and the sprite image `sprite.png` and both files must be
 placed in the same directory as the style itself. *A style compatible with the
-tiles data schema (Mapbox, OpenMapTiles, Tilezen) must be used.*
+tiles data schema (Mapbox, OpenMapTiles, Tilezen, Ordnance Survey, Esri, ...)
+must be used.*
 
 For a list of "ready to use" styles see the
 [QtPBFImagePlugin-styles](https://github.com/tumic0/QtPBFImagePlugin-styles)
@@ -51,7 +52,7 @@ repository.
 
 ## Build
 ### Requirements
-* Qt5 >= 5.12 or Qt6
+* Qt5 >= 5.11 or Qt6
 * Google Protocol Buffers (protobuf-lite)
 * Zlib
 

src/tile.h

@@ -11,7 +11,10 @@ public:
 	  : _zoom(zoom), _size(img->size()), _scale(scale),
 	  _text(QSize(img->size().width() / scale.x(),
 	  img->size().height() / scale.y())), _painter(img)
-	  {_painter.scale(scale.x(), scale.y());}
+	{
+		img->fill(Qt::transparent);
+		_painter.scale(scale.x(), scale.y());
+	}
 
 	int zoom() const {return _zoom;}
 	const QSize &size() const {return _size;}