Snippet to show usage of 'GotCursorShape' in libvncserver/libvncclient

cursor-change-snippet.cpp

/*
 * This example was written using the Qt toolkit, but you should be
 * able to get a general idea of what's going on
*/

/* ============================================================================== */

/*
 *  When you set up your libvncserver client, you need to set useRemoteCursor 
 * to true and be sure to set the callback for GotCursorShape
*/

void VncViewer::setUpVNCClient ()
{
    client = rfbGetClient(3, 3, 2);

    // client and app options
    client->canHandleNewFBSize = false;
    client->appData.qualityLevel = 3;
    client->appData.compressLevel = 3;
    client->appData.requestedDepth = 8;
    client->appData.useRemoteCursor = true;   // <===== #### THIS ONE IS IMPORTANT ###

    // callbacks
    client->GetPassword = VncViewer::password_proc;
    client->GotFrameBufferUpdate = VncViewer::fb_start_update;
    client->FinishedFrameBufferUpdate = VncViewer::fb_end_update;
    client->GotCursorShape = VncViewer::handleRemoteCursorChange;  // <===== #### THIS ONE IS IMPORTANT ###

    SetFormatAndEncodings(client);
}



/*
 * This is a simplified version of what I was using before I abandoned the project.
 * You will see that the Source and Mask are combined together by Qt to
 * create a cursor with a transparent background
 * 
 * This is the callback we set earlier when setting up the libvncserver client
 * The signature must be as shown below (rfbClient *client, int xhot...)
*/

void VncViewer::handleRemoteCursorChange (rfbClient *client, int xhot, int yhot, int width, int height, int bytesPerPixel)
{
    VncViewer* v = g.currentViewer;

    if (!v || !v->client)
        return;

    if (v->client->rcSource && v->client->rcMask) {

        QImage imgS = QImage(v->client->rcSource, width, height, width * bytesPerPixel, QImage::Format_RGB16);
        QImage imgM = QImage(width, height, QImage::Format_Mono);

        QPixmap pmCursorSource = QPixmap();
        pmCursorSource.convertFromImage(imgS);

        imgM.fromData(v->client->rcMask, width * height);

        QBitmap pmCursorMask(width, height);
        pmCursorMask.convertFromImage(imgM);

        QCursor cCursor = QCursor(pmCursorSource, pmCursorMask, xhot, yhot);

        g.viewWidget->setCursor(cCursor);
    }
}