Undefined reference to 'QRasterPaintEngine::QRasterPaintEngine(QPaintDevice*)'

sachintm

Hello All,

I am trying to use the QRasterPaintEngine to do painting operations for my project on "Qt for Embedded Linux", and getting a linking error to QRasterPaintEngine implementation.

Initially, I got the error " QRasterPaintEngine : No such file or error ", So I changed the include path to absolute path to the header files, like below

#include "/mydir/qt-everywhere-opensource-src-4.8.5/include/QtGui/private/qpaintengine_raster_p.h"

So, the compilation is working fine, but while linking it is giving the error as,

" undefined reference to 'QRasterPaintEngine::QRasterPaintEngine(QPaintDevice*)' ".

Please suggest me how to resolve the linking error.

Thanks in advance,
Sachin

sachintm

I have implemented a sample code for this.

header file "srasterpaintengine.h" looks like this.

@#ifndef SRASTERPAINTENGINE_H
#define SRASTERPAINTENGINE_H

#include <private/qpaintengine_raster_p.h>

class SRasterPaintEngine : public QObject

{

public:
SRasterPaintEngine( QPaintDevice *device );
~SRasterPaintEngine();

private:
QRasterPaintEngine *raster_engine;

};

#endif // SRASTERPAINTENGINE_H
@

and the source file "srasterpaintengine.cpp" looks like below.

@#include "srasterpaintengine.h"

SRasterPaintEngine::SRasterPaintEngine(QPaintDevice *device):raster_engine(0)
{
raster_engine = new QRasterPaintEngine(device);
}

SRasterPaintEngine::~SRasterPaintEngine()
{
if(raster_engine)
delete raster_engine;
}
@

So, when I compiled this code, I am getting the linking error.
Please suggest how to get it working.

Thanks,
Sachin

SGaist

Hi,

You know that you are trying to use private API's that are officially not to be used ?

That said, what do you need to paint that would require modification to the raster paint engine ?

sachintm

Hi,

Thanks for replying,

I am trying to hook my own GPU into the "Qt for Embedded Linux" and implement the few set of graphics operations.

Yes, I know I am using the private APIs, I am working on POCs for this.
Please suggest, if there are any other ways to do it.

Thanks,
Sachin

SGaist

In that case, you should rather integrate your code directly in Qt, that would allow you to use the private APIs directly