C++ devicePixelRatio函数代码示例

void hrRender::setScene(hrScene *s)
{
    Q_ASSERT(s);

    scene = s;
    connect(scene, SIGNAL(sceneChanged()), this, SLOT(onSceneChanged()));
    connect(scene, SIGNAL(cursorChaged(int)), this, SLOT(onCursorChanged(int)));

    scene->setViewport(width()*devicePixelRatio(), height()*devicePixelRatio());
}

void NGLScene::resizeGL(int _w , int _h)
{
  m_width=_w*devicePixelRatio();
  m_height=_h*devicePixelRatio();
  ngl::ShaderLib *shader = ngl::ShaderLib::instance();
  shader->use("buttonShader");
  shader->setRegisteredUniform("resolution", ngl::Vec2(m_width, m_height));
  shader->use("progressShader");
  shader->setRegisteredUniform("resolution", ngl::Vec2(m_width, m_height));
  m_project = ngl::perspective(45.0f, float(m_width)/float(m_height), 0.2f, 20.0f);
}

void OpenGLWindow::resizeGL(QResizeEvent *_event)
{
  /*
Note: This is merely a convenience function in order to provide an API that is compatible with QOpenGLWidget. Unlike with QOpenGLWidget, derived classes are free to choose to override
resizeEvent() instead of this function.
Note: Avoid issuing OpenGL commands from this function as there may not be
 a context current when it is invoked. If it cannot be avoided, call makeCurrent().
*/
  m_width=_event->size().width()*devicePixelRatio();
  m_height=_event->size().height()*devicePixelRatio();

}

void DisplayImagesWidgetGui::display()
{
    QImage image(m_fNames[m_fileIndex]);
    cv::Mat img_bw = Util::toCv(image, CV_8UC4);
    cv::cvtColor(img_bw, img_bw, CV_BGR2GRAY);
    QPixmap pixmap = QPixmap::fromImage(image);
    QImage scaledImage = pixmap.toImage().scaled(pixmap.size() * devicePixelRatio(),
                                                 Qt::IgnoreAspectRatio, Qt::SmoothTransformation);
    scaledImage.setDevicePixelRatio(devicePixelRatio());
    QPixmap *newScaledPixmap = new QPixmap(QPixmap::fromImage(scaledImage));
    ui->label->setScaledContents(true);
    ui->label->setPixmap(*newScaledPixmap);
    ui->label->resize(ui->label->pixmap()->size());
}

// The render function, called when an update is requested
void MainWindow::render()
{
    // glViewport is used for specifying the resolution to render
    // Uses the window size as the resolution
    const qreal retinaScale = devicePixelRatio();
    glViewport(0, 0, width() * retinaScale, height() * retinaScale);

    // Clear the screen at the start of the rendering.
    glClear(GL_COLOR_BUFFER_BIT|GL_DEPTH_BUFFER_BIT);


    // Bind the shaderprogram to use it
    m_shaderProgram->bind();
    m_shaderProgram->setUniformValue("model", model);
    m_shaderProgram->setUniformValue("view", view);
    m_shaderProgram->setUniformValue("projection", projection);
    m_funcs->glBindVertexArray(VAO);

    // Draw cube
    m_funcs->glDrawArrays(GL_TRIANGLES, 0, vectorsNumber);

    // relases the current shaderprogram (to bind an use another shaderprogram for example)
    m_shaderProgram->release();

}

void OpenGLWidget::paintGL()
{
    const qreal retinaScale = devicePixelRatio();
    glClear(GL_COLOR_BUFFER_BIT);

    glMemoryBarrier(GL_SHADER_IMAGE_ACCESS_BARRIER_BIT);

    majorOffset += offset;
    fractal.beginRender();

    if (fill)
        glPolygonMode(GL_FRONT_AND_BACK, GL_FILL);
    else
        glPolygonMode(GL_FRONT_AND_BACK, GL_LINE);

    m_vao.bind();
    glDrawElements(GL_TRIANGLES, indices.size(), GL_UNSIGNED_INT, 0);
    m_vao.release();

    fractal.endRender();
    majorOffset -= offset;

    if (go)
    {
        go = anim.nextFrame();
        fractal.computeVariables.at(0)->setValue();
        fractal.computeVariables.at(1)->setValue();
        fractal.computeVariables.at(fractal.computeVariables.size() - 1)->setValue();
        rendermodeLR = ALL;

        if (anim.checkBox->isChecked())
            this->grabFramebuffer().save(anim.file);
    }
}

void QOpenGLTextureBlitWindow::resizeEvent(QResizeEvent *event)
{
    Q_UNUSED(event);
    m_image = QImage(size() * devicePixelRatio(), QImage::Format_ARGB32_Premultiplied);

    m_image.fill(Qt::gray);

    QPainter p(&m_image);

    QPen pen(Qt::red);
    pen.setWidth(5);
    p.setPen(pen);

    QFont font = p.font();
    font.setPixelSize(qMin(m_image.height(), m_image.width()) / 20);
    p.setFont(font);

    int dx = dWidth() / 5;
    int dy = dHeight() / 5;
    for (int y = 0; y < 5; y++) {
        for (int x = 0; x < 5; x++) {
            QRect textRect(x * dx, y*dy, dx,dy);
            QString text = QString("[%1,%2]").arg(x).arg(y);
            p.drawText(textRect,text);
        }
    }

    p.drawRect(QRectF(2.5,2.5,dWidth() - 5, dHeight() - 5));

    m_image_mirrord = m_image.mirrored(false,true);
}

/**
*Overrides the paintGL method of the base class.
*Dispatches the handling to the active child application.
*/
void ThreeDWidget::paintGL()
{
	qreal pixelRatio = 1;
#if QT_VERSION >= 0x050000
	pixelRatio = devicePixelRatio();
#endif
	setupViewPort(width() * pixelRatio, height() * pixelRatio);

	if(m_iView==GLMIAREXVIEW)
	{
		QMiarex* pMiarex = (QMiarex*)s_pMiarex;
		pMiarex->GLDraw3D();
		if(pMiarex->m_iView==W3DVIEW) pMiarex->GLRenderView();
	}
	else if(m_iView == GLBODYVIEW)
	{
		GL3dBodyDlg *pDlg = (GL3dBodyDlg*)m_pParent;
		pDlg->GLDraw3D();
		pDlg->GLRenderBody();
	}
	else if(m_iView == GLWINGVIEW)
	{
		GL3dWingDlg *pDlg = (GL3dWingDlg*)m_pParent;
		pDlg->GLDraw3D();
		pDlg->GLRenderView();
	}
}

// The render function, called when an update is requested
void MainWindow::render()
{
    // glViewport is used for specifying the resolution to render
    // Uses the window size as the resolution
    const qreal retinaScale = devicePixelRatio();
    glViewport(0, 0, width() * retinaScale, height() * retinaScale);

    // Clear the screen at the start of the rendering.
    glClear(GL_COLOR_BUFFER_BIT|GL_DEPTH_BUFFER_BIT);

    // Bind the shaderprogram to use it
    m_shaderProgram->bind();
    object.bind();

   // m_shaderProgram->setUniformValue("m", model);


    view.setToIdentity();
    projection.setToIdentity();

    projection.perspective(30.0, 1, 50, 1000);
    //view.rotate(-200,-200,-200);
    view.translate(-200,-200,-1000);

    m_shaderProgram->setUniformValue("v", view);
    m_shaderProgram->setUniformValue("p", projection);
    renderRaytracerScene();

    // relases the current shaderprogram (to bind an use another shaderprogram for example)
    m_shaderProgram->release();
}

      QSize TuningLayout::calculateSize(SizeType sizeType) const
      {
        int _border = 2;
        int _width = 0;
        int _height = _border;

        auto _parent = static_cast<Tuning*>(parent());

        for (auto& _item : items_)
        {
          switch (_item.role_)
          {
          case Role::PARAMETER:
          case Role::TITLE:
            _height += 24 / _parent->devicePixelRatio();
            break;
          case Role::PREVIEW:
            if (!tuning()) continue;
            /// Increase height by aspect ratio
            _height += _parent->width() /
                       float(tuning()->width()) * tuning()->height();
            break;
          }
        }
        _height += _border;

        return QSize(_width,_height);
      }

/**
 * @param pos A point in Qt screen coordinates from, for example, a mouse click
 * @return A QPointF defining the position in data coordinates
 */
QPointF FigureCanvasQt::toDataCoords(QPoint pos) const {
  // There is no isolated method for doing the transform on matplotlib's
  // classes. The functionality is bound up inside other methods
  // so we are forced to duplicate the behaviour here.
  // The following code is derived form what happens in
  // matplotlib.backends.backend_qt5.FigureCanvasQT &
  // matplotlib.backend_bases.LocationEvent where we transform first to
  // matplotlib's coordinate system, (0,0) is bottom left,
  // and then to the data coordinates
  const int dpiRatio(devicePixelRatio());
  const double xPosPhysical = pos.x() * dpiRatio;
  GlobalInterpreterLock lock;
  // Y=0 is at the bottom
  double height = PyFloat_AsDouble(
      Python::Object(m_figure.pyobj().attr("bbox").attr("height")).ptr());
  const double yPosPhysical =
      ((height / devicePixelRatio()) - pos.y()) * dpiRatio;
  // Transform to data coordinates
  QPointF dataCoords;
  try {
    auto invTransform = gca().pyobj().attr("transData").attr("inverted")();
    NDArray transformed = invTransform.attr("transform_point")(
        Python::NewRef(Py_BuildValue("(ff)", xPosPhysical, yPosPhysical)));
    auto rawData = reinterpret_cast<double *>(transformed.get_data());
    dataCoords =
        QPointF(static_cast<qreal>(rawData[0]), static_cast<qreal>(rawData[1]));
  } catch (Python::ErrorAlreadySet &) {
    PyErr_Clear();
    // an exception indicates no transform possible. Matplotlib sets this as
    // an empty data coordinate so we will do the same
  }
  return dataCoords;
}

      void TuningLayout::setGeometry(QRect const& _rect)
      {
        if (!tuning()) return;

        const int _border = 2;
        int _height       = _border;

        auto _parent = static_cast<Tuning *>(parent());

        /// Adjust geometry for each widget
        for (auto& _item : items_)
        {
          auto _widget = _item.widget();

          /// Widget height is constant except for preview
          int _widgetHeight = _item.role_ == Role::PREVIEW ? _parent->width() /
                              float(tuning()->width()) * tuning()->height() :
                              36 / _parent->devicePixelRatio();
          _widget->setGeometry(_border, _height,
                               _parent->width() - _border * 2, _widgetHeight);
          _widget->show();

          /// Increase height
          _height += _widgetHeight;
        }
      }

void FontWindow::render()
{
    m_program->bind();
    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
    m_modelView.setToIdentity();
    m_modelView.translate(0.0f, 0.0f, -3.0f);
    QVector4D color(1.0f*float(qCos(m_cnt1)),
                    1.0f*float(qSin(m_cnt2)),
                    1.0f-0.5f*float(qCos(m_cnt1+m_cnt2)),
                    1.0f);
    m_program->setUniformValue("color", color);
    m_program->setUniformValue("mvpMatrix", m_projection * m_modelView);

    const qreal retinaScale = devicePixelRatio();
    resizeGL(width()*retinaScale, height()*retinaScale);

    float sx = 2.0 / width()*retinaScale;
    float sy = 2.0 / height()*retinaScale;
    FT_Set_Pixel_Sizes(m_ftFace, 0, 48);

    float mx = float(cos(m_cnt1));
    float my = float(sin(m_cnt2));
    QString text = "Active OpenGL Text With NeHe - " + QString::number(m_cnt1, 'f', 2);
    renderText(text.toLatin1().data(),
                mx - 0.5, my, sx, sy);
    m_program->release();

    m_cnt1+=0.051f;
    m_cnt2+=0.005f;
}

bool IBLWidget::recreateFBO()
{
    mSize = width() < height() ? width() : height();
    mSize *= devicePixelRatio();

    // if the FBO is the right size, no need to create it
    if( fbo && fbo->width() == mSize && fbo->height() == mSize )
        return false;

    if(quad) delete quad;
    quad = new Quad(0.f, 0.f, mSize, mSize, 0.f, 0.f, 1.f, 1.f);

    if (fbo) delete fbo;
    if (comp) delete comp;

    fbo = new DGLFrameBuffer( mSize, mSize, "FBO" );
    fbo->addColorBuffer( 0, GL_RGBA32F );
    fbo->addDepthBuffer();
    fbo->checkStatus();

    comp = new DGLFrameBuffer( mSize, mSize, "Comp" );
    comp->addColorBuffer( 0, GL_RGBA32F );
    comp->checkStatus();

    glf->glDisable( GL_BLEND );
    resetComps();

    return true;
}

void QVistaBackButton::paintEvent(QPaintEvent *)
{
    QPainter p(this);
    QRect r = rect();
    HANDLE theme = pOpenThemeData(0, L"Navigation");
    //RECT rect;
    QPoint origin;
    const HDC hdc = QVistaHelper::backingStoreDC(parentWidget(), &origin);
    RECT clipRect;
    int xoffset = origin.x() + QWidget::mapToParent(r.topLeft()).x() - 1;
    int yoffset = origin.y() + QWidget::mapToParent(r.topLeft()).y() - 1;
    const int dpr = devicePixelRatio();
    const QRect rDp = QRect(r.topLeft() * dpr, r.size() * dpr);
    const int xoffsetDp = xoffset * dpr;
    const int yoffsetDp = yoffset * dpr;

    clipRect.top = rDp.top() + yoffsetDp;
    clipRect.bottom = rDp.bottom() + yoffsetDp;
    clipRect.left = rDp.left() + xoffsetDp;
    clipRect.right = rDp.right()  + xoffsetDp;

    int state = WIZ_NAV_BB_NORMAL;
    if (!isEnabled())
        state = WIZ_NAV_BB_DISABLED;
    else if (isDown())
        state = WIZ_NAV_BB_PRESSED;
    else if (underMouse())
        state = WIZ_NAV_BB_HOT;

    WIZ_NAVIGATIONPARTS buttonType = (layoutDirection() == Qt::LeftToRight
                                      ? WIZ_NAV_BACKBUTTON
                                      : WIZ_NAV_FORWARDBUTTON);

    pDrawThemeBackground(theme, hdc, buttonType, state, &clipRect, &clipRect);
}