How convert text to pixel array in QT - c++

Question

I'm new user of QT. Is it possible to convert for example one character or string to array where 0 means white field and 1 means black field? For example when I have character "a" saved as QString or any representation of font and I would like to get following array:
int array[9][6] = { //"a" char array
{0, 0, 0, 0, 0, 0}, //- - - - - -
{0, 1, 1, 1, 1, 0}, //- * * * * -
{1, 0, 0, 0, 0, 1}, //* - - - - *
{0, 0, 0, 0, 0, 1}, //- - - - - *
{0, 1, 1, 1, 1, 1}, //- * * * * *
{1, 0, 0, 0, 0, 1}, //* - - - - *
{1, 0, 0, 0, 1, 1}, //* - - - * *
{0, 1, 1, 1, 0, 1}, //- * * * - *
{0, 0, 0, 0, 0, 0}, //- - - - - -
};
Is there any way in QT for reach that goal ? I hope I describe my problem as clear as possible and someone can help me with this?
And very important thing size array must depend on selected font size, so if I choose for example 30 pt font, array should be appropriate bigger than 10 pt font.
Thank You very much.
Best regards.

Answer 1

You can draw text onto a bitmap image, which will give you a bitmap containing text. Which is a pixel array, for all intents and purposes.
Note that you will also have to use a "bitmap font", regular fonts won't really do the trick as most have been created to utilize antialiasing and won't result in a crisp and readable bitmap image.
Qt also offers font metrics, which can give you a clear idea how big text or individual characters are.

Answer 2

I misinterpreted the question on my first read through... well, here is what was asked for...
#include <QApplication>
#include <QPixmap>
#include <QLabel>
#include <QPainter>
#include <QDebug>
#include <QVector>
#include <QFontMetrics>
int main(int argc, char *argv[])
{
QApplication a(argc, argv);
QSize size;
// QPixmap pixmap(100,100);
QImage image(20,20, QImage::Format_Mono);// Change the width and height here as needed if your letters get too big
image.fill(0);
{
QPainter painter(&image);
//// alternative to fill method
// painter.setBrush(Qt::black);
// painter.drawRect(0,0,image.width(), image.height());
painter.setPen(Qt::white);
QFontMetrics fm(painter.font());
size.setHeight(fm.height());
size.setWidth(fm.width('a'));
painter.drawText(0,fm.height(),"a");
}
QLabel label;
label.setPixmap(QPixmap::fromImage(image).scaled(400,400, Qt::KeepAspectRatio));
label.show();
QVector <QVector <int> > array(size.height(), QVector < int> (size.width(), 0));
for(int r = 0; r < size.height(); r++)
for(int c = 0; c < size.width(); c++)
array[r][c] = (image.pixelColor(c,r) == Qt::white ? 1 : 0);
// qDebug() << size << array;
foreach(QVector <int> row, array)
qDebug() << row;
return a.exec();
}
Output:
QVector(0, 0, 0, 0, 0, 0)
QVector(0, 0, 0, 0, 0, 0)
QVector(0, 0, 0, 0, 0, 0)
QVector(0, 0, 0, 0, 0, 0)
QVector(0, 0, 0, 0, 0, 0)
QVector(0, 0, 0, 0, 0, 0)
QVector(0, 0, 0, 0, 0, 0)
QVector(0, 1, 1, 1, 0, 0)
QVector(0, 0, 0, 0, 1, 0)
QVector(0, 1, 1, 1, 1, 0)
QVector(1, 0, 0, 0, 1, 0)
QVector(1, 0, 0, 0, 1, 0)
QVector(0, 1, 1, 1, 1, 0)