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Re: More: simple graphics on X



> 
> I looked both at Qt and GTK+ examples and couldn't find
> how to make a simple window to plot into
> 
> I wrote:
> >
> > hi
> >
> > can anyone point me to sources on the web which explin how to make
> > simple X bitmap manipulations ?
> >
> > i need to creat a bitmap on X, and set/clear pixels on real time
> > form a program in c/c++
> >
> > thanks
> > erez.
here is a small Qt example on simple bitmap manipulating
the theory is simple.
you create a qpixmap object.
you paint on it wit a qpainter.
you transfer it to the widget/ write it in the widgets paint
event
--- jail.cpp  ----
 #include <qapplication.h>
// the following two classes are what is interesting for you
#include <qpixmap.h>
#include <qpainter.h>
int main( int argc, char **argv )
{
    QApplication a( argc, argv );
    QWidget w;
    w.resize( 300, 300 );
    // create a pixmap object -- note that you could load a pixmap with
    //the constructur that gets a file name as a param..
    QPixmap pm(w.width(),w.height());
    // create a painter object to work on the pixmap
    QPainter p(&pm);
    // do the pixel manipulation you want this is just an example
    QColorGroup g=w.colorGroup();
    p.fillRect(pm.rect(),g.base());
    p.setBrush(g.foreground());
    for (int i=0;i<=pm.width();i++)
      for (int j=0;j<=pm.height();j++)             
	if (i%8==0||j%8==0)
          p.drawPoint(i,j);
    // end the painting on the pixmap
    p.end();
    // transfer the stuff to the widget -- there are other methods, this is
    // just one example..
    w.setBackgroundPixmap(pm);
    // show the widget
    a.setMainWidget( &w );
    w.show();
    return a.exec();
}