C++ QTransform函数代码示例

void Scene::mouseReleaseEvent(QGraphicsSceneMouseEvent *e)
{
    auto hoverItem = itemAt(e->scenePos(), QTransform());
    if (!hoverItem && _nodesInteractable) {
        auto node = new Node;
        node->setInteractable(_nodesInteractable);
        node->setSelected(true);
        node->setPos(e->scenePos());
        addItem(node);
    } else if (!_nodesInteractable && _currentEdge) {
        auto nodeItem = dynamic_cast<Node *>(hoverItem);
        if (nodeItem) {
            _currentEdge->setEndNode(nodeItem);
        } else {
            removeItem(_currentEdge);
            delete _currentEdge;
        }
        _currentEdge = nullptr;
    }

    QGraphicsScene::mouseReleaseEvent(e);
}

void DesktopWidget::spin()
{
    d->angle += 18;
    setCacheMode(ItemCoordinateCache);
    QPointF center = boundingRect().center();
    QTransform mat = QTransform();
    mat.translate(center.x() ,  center.y());
    mat.rotate(d->angle, Qt::YAxis);
    mat.translate(- center.x() ,  - center.y());
    setTransform(mat);
    if (d->angle >= 180) {
        if (state() == BACKSIDE) {
            setState(NORMALSIDE);
        } else {
            setState(BACKSIDE);
        }
        d->spintimer->stop();
        resetMatrix();
        setCacheMode(DeviceCoordinateCache);
        d->angle = 0;
    }
}

void svg_renderer::update_cache_item (const renderable_item *item, const render_cache_id &cache_id, const QTransform &transform,
                                      renderer_config &cfg, int total_x, int total_y)
{
  int block_size = rendered_items_cache::block_pixel_size ();
  SkBitmap bitmap;
  bitmap.setConfig (SkBitmap::kARGB_8888_Config, block_size * total_x, block_size * total_y);
  bitmap.allocPixels ();
  SkBitmapDevice device (bitmap);
  SkCanvas canvas (&device);
  canvas.drawColor (SK_ColorTRANSPARENT, SkXfermode::kSrc_Mode);

  QRectF local_rect = cache_id.pixel_rect (transform);
  QTransform last_inverted = transform.inverted ();
  QPointF last_pos_local = last_inverted.map (QPointF (0, 0));
  QPointF cur_pos_local = last_inverted.map (QPointF (local_rect.x (), local_rect.y ()));
  QPointF diff = -cur_pos_local + last_pos_local;

  QTransform pixmap_transform = QTransform (transform).translate (diff.x (), diff.y ());
  renderer_state state (QRect (0, 0, block_size * total_x, block_size * total_y), pixmap_transform);
  draw_item (item, canvas, state, cfg);

  if (m_queue->is_interrupted ())
    return;

  if (total_x == total_y && total_x == 1)
    m_cache->add_bitmap (cache_id, bitmap, cfg.use_new_cache ());
  else
    {
      for (int i = 0; i < total_x; i++)
        for (int j = 0; j < total_y; j++)
          {
            render_cache_id cur_id (cache_id.x () + i, cache_id.y () + j, cache_id.object_type ());
            SkBitmap bitmap_part;
            DEBUG_ASSERT (bitmap.extractSubset (&bitmap_part, SkIRect::MakeXYWH (i * block_size, j * block_size, block_size, block_size)));
            m_cache->add_bitmap (cur_id, bitmap_part, cfg.use_new_cache ());
          }
    }

}

QImage QWindowsFontEngineDirectWrite::alphaMapForGlyph(glyph_t glyph, QFixed subPixelPosition)
{
    QImage im = imageForGlyph(glyph, subPixelPosition, 0, QTransform());

    QImage indexed(im.width(), im.height(), QImage::Format_Indexed8);
    QVector<QRgb> colors(256);
    for (int i=0; i<256; ++i)
        colors[i] = qRgba(0, 0, 0, i);
    indexed.setColorTable(colors);

    for (int y=0; y<im.height(); ++y) {
        uint *src = (uint*) im.scanLine(y);
        uchar *dst = indexed.scanLine(y);
        for (int x=0; x<im.width(); ++x) {
            *dst = 255 - (m_fontEngineData->pow_gamma[qGray(0xffffffff - *src)] * 255. / 2047.);
            ++dst;
            ++src;
        }
    }

    return indexed;
}

bool TemplateTrack::loadTemplateFileImpl(bool configuring)
{
	if (!track.loadFrom(template_path, false))
		return false;
	
	if (!configuring)
	{
		Georeferencing* track_crs = new Georeferencing();
		if (!track_crs_spec.isEmpty())
			track_crs->setProjectedCRS(QString{}, track_crs_spec);
		track_crs->setTransformationDirectly(QTransform());
		track.setTrackCRS(track_crs);
		
		bool crs_is_geographic = track_crs_spec.contains(QLatin1String("+proj=latlong"));
		if (!is_georeferenced && crs_is_geographic)
			calculateLocalGeoreferencing();
		else
			track.changeMapGeoreferencing(map->getGeoreferencing());
	}
	
	return true;
}

void CGraphicsScene::mouseMoveEvent(QGraphicsSceneMouseEvent* event)
{
  //  static int nbMove=0;
  //qDebug("CGraphicsScene::mouseMoveEvent %i", m_mode);
  
  switch (m_mode)
  {
    case MODE_IDLE:
      QGraphicsScene::mouseMoveEvent(event);

      if (m_itemRect != NULL)
      {
        m_itemRect->setMoveablePoint(event->scenePos());
        setSelectionArea(m_itemRect->path(), QTransform());
      }
      
      break;
    case MODE_CREATE_ITEM:
      //Q_ASSERT(false); //Normallement ne doit jamais arrive...
      QGraphicsScene::mouseMoveEvent(event);
      break;
      
    case MODE_IN_ITEM_CREATION:
      Q_ASSERT(m_currentItem != NULL);
      m_currentItem->updateCurrentPoint(event->scenePos());
      //QGraphicsScene::mouseMoveEvent(event); pas d'appel a la classe de base pour eviter les moves en meme temps que les creations d'item
      break;
      
    case MODE_IN_ITEM_EVOLUTION:
      Q_ASSERT(m_currentItem != NULL);
      m_currentItem->onMouseEventOnAnchor(event, m_pressedAnchor);
      break;
      
    default:
      Q_ASSERT(false);
      break;
  }
}

void MapWidget::setViewOnRobot(std::string robot_id)
{
	if (active_view_on_robot_ == robot_id)
	{
		return;
	}

	RobotGraphicsItem* robot = getRobot(robot_id);

	QPointF position;
	double heading;

	getRobotPosition("/"+robot_id+"/base_link", position, heading);

	graphicsView_->setTransform(QTransform());

	graphicsView_->centerOn(position.x(),position.y());

	// graphicsView_->scale(1, -1);
	graphicsView_->scale(56, -56);

	active_view_on_robot_ = robot_id;
}

void BlurPicker::setIndex(qreal index)
{
    m_index = index;

    qreal baseline = 0;
    for (int i = 0; i < m_icons.count(); ++i) {
        ImageItem *icon = m_icons[i];
        qreal a = ((i + m_index) * 2 * M_PI) / m_icons.count();
        qreal xs = 380 * qSin(a);
        qreal ys = 230 * qCos(a);
        QPointF pos(xs, ys);
       // pos = QTransform::scale(0,0.2).map(pos);
//        pos = QTransform().rotate(-20).map(pos);
        pos = QTransform().rotate(-5).map(pos);
        pos -= QPointF(40, 40);
//        pos -= QPoint(10,10);
        icon->setPos(pos);
        baseline = qMax(baseline, ys);
        static_cast<BlurEffect *>(icon->graphicsEffect())->setBaseLine(baseline);
    }

    scene()->update();
}

void MainWindow::editListUpdateGraphics()
{
    editListChordScene->clear();
    editListChordScene->addPixmap(*guitarArm);
    ui->editChordGraphicsView->setTransform(QTransform());

    QString mainChord = ui->editNormalChordsComboBox->currentText();
    QString modifier = ui->editChordsModificatorsComboBox->currentText();
    QVarLengthArray<int> frets = getFrets(mainChord, modifier);

    Braco * braco = new Braco(648, 6, 144);
    Point * point = NULL;

    for (int i = 0; i < frets.size(); i++)
        if (frets.at(i) != 0 && frets.at(i) != -1)
        {
            point = braco->getPoint(i, frets.at(i));
            editListChordScene->addEllipse(point->X, point->Y, 9, 9, QPen(Qt::NoPen), QBrush(QColor(255, 153, 0)));
        }

    delete point;
    delete braco;
}

void ScreeniePixmapItem::updateItemGeometry()
{
    QTransform transform;
    QTransform scale;
    QTransform translateBack;

    qreal centerScale = 1.0 - 0.9 * d->screenieModel.getDistance() / SceneLimits::MaxDistance;
    scale = QTransform().scale(centerScale, centerScale);

    QPixmap pixmap = this->pixmap();
    qreal dx = pixmap.width() / 2.0;
    qreal dy;
    if (d->screenieModel.isReflectionEnabled()) {
        dy =  pixmap.height() / 4.0;
    } else {
        dy = pixmap.height() / 2.0;
    }
    transform.translate(dx, dy);
    transform.rotate(d->screenieModel.getRotation(), Qt::YAxis);
    translateBack.translate(-dx, -dy);
    transform = translateBack * scale * transform;
    setTransform(transform, false);
}

/*!
    \reimp
*/
void QGraphicsDropShadowEffect::draw(QPainter *painter)
{
    Q_D(QGraphicsDropShadowEffect);
    if (d->filter->blurRadius() <= 0 && d->filter->offset().isNull()) {
        drawSource(painter);
        return;
    }

    PixmapPadMode mode = PadToEffectiveBoundingRect;
    if (painter->paintEngine()->type() == QPaintEngine::OpenGL2)
        mode = NoPad;

    // Draw pixmap in device coordinates to avoid pixmap scaling.
    QPoint offset;
    const QPixmap pixmap = sourcePixmap(Qt::DeviceCoordinates, &offset, mode);
    if (pixmap.isNull())
        return;

    QTransform restoreTransform = painter->worldTransform();
    painter->setWorldTransform(QTransform());
    d->filter->draw(painter, offset, pixmap);
    painter->setWorldTransform(restoreTransform);
}

void NodeLabel::updateStyle()
{
    prepareGeometryChange();
    // update the text position
    m_text.prepare(QTransform(), s_font);
    QSizeF textSize = m_text.size();
    m_textPos = QPointF(textSize.width() / -2., textSize.height() / -2.);
    // update the label
    QSizeF labelSize =
        QSizeF(qMax(textSize.width(), Node::getCoreRadius() * 2.),
               textSize.height());
    m_outlineRect =
        QRectF((labelSize.width() / -2.) - s_horizontalMargin,
               m_textPos.y() - s_verticalMargin,
               labelSize.width() + (s_horizontalMargin * 2.),
               textSize.height() + (s_verticalMargin * 2.));
    // update bounding rectangle
    qreal halfLine = s_outlineWidth * 0.5;
    m_boundingRect =
        m_outlineRect.
        marginsAdded(QMarginsF(halfLine, halfLine, halfLine, halfLine));
    update();
}

void VideoItem::paintExtDockFace(QPainter *p, const QStyleOptionGraphicsItem *e,
                                 QWidget *widget) {

  p->setRenderHints(QPainter::SmoothPixmapTransform | QPainter::Antialiasing |
                    QPainter::HighQualityAntialiasing);

  p->setPen(QColor(215, 255, 98));
  p->setFont(QFont("Bitstream Charter", 12));
  //  p->drawText(QRect(8,5,64,64), Qt::AlignCenter ,"Video" ) ;
  p->save();
  QPointF center = e->exposedRect.center();
  QTransform mat = QTransform();
  mat.translate(center.x(), center.y());
  mat.rotate(-9.44, Qt::ZAxis);
  mat.translate(-center.x(), -center.y());
  // mat.shear(0.02,-0.01);
  p->setTransform(mat);
  p->setOpacity(0.8);
  if (snapped == true)
    p->drawPixmap(15, 43, e->exposedRect.width() - 30,
                  e->exposedRect.height() - 63, snap);
  p->restore();
}

void ImageWidget::paint(QPainter& painter)
{
  SYNC_WITH(imageView.console);

  const DebugImage* image = nullptr;
  RobotConsole::Images& currentImages = imageView.upperCam ? imageView.console.upperCamImages : imageView.console.lowerCamImages;
  RobotConsole::Images::const_iterator i = currentImages.find(imageView.background);

  if(i != currentImages.end())
  {
    image = i->second.image;
    imageWidth = image->getImageWidth();
    imageHeight = image->height;
  }
  else if(!currentImages.empty())
  {
    imageWidth = currentImages.begin()->second.image->getImageWidth();
    imageHeight = currentImages.begin()->second.image->height;
  }

  const QSize& size = painter.window().size();
  float xScale = float(size.width()) / float(imageWidth);
  float yScale = float(size.height()) / float(imageHeight);
  scale = xScale < yScale ? xScale : yScale;
  scale *= zoom;
  float imageXOffset = (float(size.width()) - float(imageWidth) * scale) * 0.5f + float(offset.x()) * scale;
  float imageYOffset = (float(size.height()) - float(imageHeight) * scale) * 0.5f + float(offset.y()) * scale;

  painter.setTransform(QTransform(scale, 0, 0, scale, imageXOffset, imageYOffset));

  if(image)
    paintImage(painter, *image);
  else
    lastImageTimeStamp = 0;

  paintDrawings(painter);
}

bool
MozQOrientationSensorFilter::filter(QOrientationReading* reading)
{
    switch (reading->orientation()) {
    //The Top edge of the device is pointing up.
    case QOrientationReading::TopDown:
        mWindowRotationAngle = 90;
        break;
    //The Top edge of the device is pointing down.
    case QOrientationReading::TopUp:
        mWindowRotationAngle = 270;
        break;
    //The Left edge of the device is pointing up.
    case QOrientationReading::LeftUp:
        mWindowRotationAngle = 180;
        break;
    //The Right edge of the device is pointing up.
    case QOrientationReading::RightUp:
        mWindowRotationAngle = 0;
        break;
    //The Face of the device is pointing up.
    case QOrientationReading::FaceUp:
    //The Face of the device is pointing down.
    case QOrientationReading::FaceDown:
    //The orientation is unknown.
    case QOrientationReading::Undefined:
    default:
        return true;
    }

    mWindowRotationTransform = QTransform();
    mWindowRotationTransform.rotate(mWindowRotationAngle);

    emit orientationChanged();

    return true; // don't store the reading in the sensor
}