(C++) QPixmapExample1

 

Technical facts

 

Application type(s)

• Desktop application

Operating system(s) or programming environment(s)

• Lubuntu 15.04 (vivid)

IDE(s):

• Qt Creator 3.1.1

Project type:

• GUI application

C++ standard:

• C++11

Compiler(s):

• G++ 4.9.2

Libraries used:

• Qt: version 5.4.1 (32 bit)
• STL: GNU ISO C++ Library, version 4.9.2

 

 

 

 

 

Qt project file: ./CppQPixmapExample1/CppQPixmapExample1.pro

 

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win32 {   # Windows only   message("Console application, built for Windows")   QMAKE_CXXFLAGS += -std=c++11 -Wall -Wextra -Weffc++ } macx {   # Mac only   message("Console application, built for Mac")   QMAKE_CXXFLAGS = -mmacosx-version-min=10.7 -std=gnu0x -stdlib=libc+   CONFIG +=c++11 } unix:!macx{   # Linux only   message("Console application, built for Linux")   QMAKE_CXXFLAGS += -Werror   QMAKE_CXXFLAGS += -std=c++11 -Wall -Wextra -Weffc++ } cross_compile {   # Crosscompile only   message("Console application, cross-compiling from Linux to Windows")   QMAKE_CXXFLAGS += -std=c++11 -Wall -Wextra -Weffc++ } # Go ahead and use Qt.Core: it is about as platform-independent as # the STL and Boost QT += core # Go ahead and use Qt.Gui: it is about as platform-independent as # the STL and Boost. It is needed for QImage QT += gui # Don't define widgets: it would defy the purpose of this console # application to work non-GUI #greaterThan(QT_MAJOR_VERSION, 4): QT += widgets CONFIG   += console CONFIG   -= app_bundle TEMPLATE = app # # # Type of compile # # CONFIG(release, debug|release) {   DEFINES += NDEBUG NTRACE_BILDERBIKKEL } SOURCES += main.cpp

 

 

 

 

 

./CppQPixmapExample1/main.cpp

 

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#pragma GCC diagnostic push #pragma GCC diagnostic ignored "-Weffc++" #pragma GCC diagnostic ignored "-Wunused-local-typedefs" #pragma GCC diagnostic ignored "-Wunused-but-set-parameter" #include <QImage> #include <QPixmap> #pragma GCC diagnostic pop QPixmap CreatePixmap(const int width, const int height, const int z) {   QPixmap pixmap(width,height);   QImage image = pixmap.toImage();   for (int y=0;y!=height;++y)   {     for (int x=0;x!=width;++x)     {       image.setPixel(         QPoint(x,y), //Position         qRgb((x+z+0)%256,(y+z+0)%256,(x+y+z)%256) //Color         /*         QColor( //Color           (x+z+0)%256,           (y+z+0)%256,           (x+y+z)%256)         .rgb()         */       );     }   }   pixmap = QPixmap::fromImage(image);   return pixmap; } int main() {   //Cannot create a QPixmap here, because of the following error:   //   //  QPixmap: Must construct a QApplication before a QPaintDevice   //   //QPixmap pixmap = CreatePixmap(32,32,128);   //pixmap.save("CppQPixmapExample1.png");   //QImage image = pixmap.toImage();   //image.save("CppQPixmapExample1.png"); }