Created
March 20, 2012 14:00
-
-
Save jjgod/2135911 to your computer and use it in GitHub Desktop.
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
#include <QPainter> | |
#include <QGuiApplication> | |
#include <QTextLayout> | |
#include <QElapsedTimer> | |
#include <QWindow> | |
#include <QScreen> | |
#include <QImage> | |
#include <QOpenGLContext> | |
#include <QOpenGLPaintDevice> | |
#include <QDebug> | |
class Window : public QWindow | |
{ | |
public: | |
Window(QScreen *screen = 0); | |
protected: | |
void exposeEvent(QExposeEvent *); | |
private: | |
void render(); | |
QImage m_buffer; | |
QTextLayout m_layout; | |
QOpenGLContext *m_context; | |
}; | |
Window::Window(QScreen *screen) | |
: QWindow(screen) | |
{ | |
setSurfaceType(QSurface::OpenGLSurface); | |
setGeometry(QRect(0, 0, 400, 400)); | |
create(); | |
m_context = new QOpenGLContext(this); | |
m_context->create(); | |
m_buffer = QImage(geometry().size(), QImage::Format_ARGB32_Premultiplied); | |
QFont font = QFont("Monospace"); | |
font.setPixelSize(12); | |
m_layout.setFont(font); | |
QTextOption option; | |
m_layout.setTextOption(option); | |
m_layout.setText(QString::fromUtf8("Hello. Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua.")); | |
m_layout.beginLayout(); | |
qreal height = 0; | |
while (1) { | |
QTextLine line = m_layout.createLine(); | |
if (!line.isValid()) | |
break; | |
line.setLineWidth(geometry().size().width()); | |
line.setPosition(QPointF(0, height)); | |
height += line.height(); | |
} | |
m_layout.endLayout(); | |
} | |
void Window::exposeEvent(QExposeEvent *) | |
{ | |
render(); | |
} | |
void Window::render() | |
{ | |
{ | |
m_buffer.fill(Qt::white); | |
QPainter p(&m_buffer); | |
QElapsedTimer t; | |
t.start(); | |
m_layout.draw(&p, QPointF(0, 0)); | |
} | |
QRect rect(QPoint(), geometry().size()); | |
m_context->makeCurrent(this); | |
QOpenGLPaintDevice device(rect.size()); | |
QPainter p(&device); | |
p.drawImage(0, 0, m_buffer); | |
p.end(); | |
m_context->swapBuffers(this); | |
} | |
int main(int argc, char *argv[]) | |
{ | |
QGuiApplication app(argc, argv); | |
Window a; | |
a.show(); | |
return app.exec(); | |
} |
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment