After Simon and Paul made some advancements to Qt’s font rendering system, it’s possible to render fonts in Qt running in Tty / console mode; that is, you don’t need an X11 connection. That means that the last piece of the puzzle is in place to use Qt for CGI scripting. It sort of always worked, but now also for text. Guess what this is:

It’s a screenshot of output generated from a Qt CGI script based on Graphics View. Here’s how to do it:

#include <QtGui>

int main(int argc, char **argv)
{
    QApplication app(argc, argv, QApplication::Tty);

Create your QApp with QApplication::Tty (former ‘false’) to run in console mode.

    QGraphicsScene scene;
    scene.addEllipse(QRectF(0, 0, 100, 100), QPen(Qt::black, 2), QBrush(QColor(64, 78, 128, 192)));

Create a scene, just anything. Text, shapes, or your existing scene. Try adding text and see it work.

    QImage image(scene.itemsBoundingRect().size().toSize(), QImage::Format_ARGB32_Premultiplied);
    image.setColorTable(QVector() << Qt::transparent);
    image.fill(0);

Prepare a suitably-sized transparent image.

    QPainter painter(&image);
    painter.setRenderHint(QPainter::Antialiasing);
    scene.render(&painter);
    painter.end();

Render the scene onto the image.

    QBuffer buffer;
    buffer.open(QIODevice::WriteOnly);
    QImageWriter writer(&buffer, "png");
    writer.write(image);

Use QImageWriter to stuff the image into a QBuffer so that we can get its size for…

    printf("Content-Type: image/png; name="image.png"rn");
    printf("Content-Length: %drn", int(buffer.size()));
    printf("rn");

…the CGI header. Finally,

    QFile file;
    file.open(stdout, QIODevice::WriteOnly);
    file.write(buffer.data(), buffer.data().size());
    return 0;
}

Dump the image to stdout, compile, and copy your new script to your public_html/cgi-bin directory.

Disclaimer: This happens to work, tested in 4.3 snapshots only, may work with 4.2, and the snapshots may change at any time. It’s not officially supported.