window.cpp Example File

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  #include "window.h"

  #include <QMouseEvent>
  #include <QOpenGLWindow>
  #include <QOpenGLTexture>
  #include <QOpenGLFunctions>
  #include <QMatrix4x4>

  #include "compositor.h"
  #include <QtWaylandCompositor/qwaylandseat.h>

  Window::Window()
  {
  }

  void Window::setCompositor(Compositor *comp) {
      m_compositor = comp;
      connect(m_compositor, &Compositor::startMove, this, &Window::startMove);
      connect(m_compositor, &Compositor::startResize, this, &Window::startResize);
      connect(m_compositor, &Compositor::dragStarted, this, &Window::startDrag);
  }

  void Window::initializeGL()
  {
      QImage backgroundImage = QImage(QLatin1String(":/background.jpg")).rgbSwapped();
      backgroundImage.invertPixels();
      m_backgroundTexture = new QOpenGLTexture(backgroundImage, QOpenGLTexture::DontGenerateMipMaps);
      m_backgroundTexture->setMinificationFilter(QOpenGLTexture::Nearest);
      m_backgroundImageSize = backgroundImage.size();
      m_textureBlitter.create();
  }

  void Window::drawBackground()
  {
      for (int y = 0; y < height(); y += m_backgroundImageSize.height()) {
          for (int x = 0; x < width(); x += m_backgroundImageSize.width()) {
              QMatrix4x4 targetTransform = QOpenGLTextureBlitter::targetTransform(QRect(QPoint(x,y), m_backgroundImageSize), QRect(QPoint(0,0), size()));
              m_textureBlitter.blit(m_backgroundTexture->textureId(),
                                targetTransform,
                                QOpenGLTextureBlitter::OriginTopLeft);
          }
      }
  }

  QPointF Window::getAnchorPosition(const QPointF &position, int resizeEdge, const QSize &windowSize)
  {
      float y = position.y();
      if (resizeEdge & QWaylandXdgSurfaceV5::ResizeEdge::TopEdge)
          y += windowSize.height();

      float x = position.x();
      if (resizeEdge & QWaylandXdgSurfaceV5::ResizeEdge::LeftEdge)
          x += windowSize.width();

      return QPointF(x, y);
  }

  QPointF Window::getAnchoredPosition(const QPointF &anchorPosition, int resizeEdge, const QSize &windowSize)
  {
      return anchorPosition - getAnchorPosition(QPointF(), resizeEdge, windowSize);
  }

  void Window::paintGL()
  {
      m_compositor->startRender();
      QOpenGLFunctions *functions = context()->functions();
      functions->glClearColor(1.f, .6f, .0f, 0.5f);
      functions->glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

      m_textureBlitter.bind();
      drawBackground();

      functions->glEnable(GL_BLEND);
      functions->glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);

      GLenum currentTarget = GL_TEXTURE_2D;
      Q_FOREACH (View *view, m_compositor->views()) {
          if (view->isCursor())
              continue;
          auto texture = view->getTexture();
          if (!texture)
              continue;
          if (texture->target() != currentTarget) {
              currentTarget = texture->target();
              m_textureBlitter.bind(currentTarget);
          }
          QWaylandSurface *surface = view->surface();
          if ((surface && surface->hasContent()) || view->isBufferLocked()) {
              QSize s = view->size();
              if (!s.isEmpty()) {
                  if (m_mouseView == view && m_grabState == ResizeGrab && m_resizeAnchored)
                      view->setPosition(getAnchoredPosition(m_resizeAnchorPosition, m_resizeEdge, s));
                  QPointF pos = view->position() + view->parentPosition();
                  QRectF surfaceGeometry(pos, s);
                  auto surfaceOrigin = view->textureOrigin();
                  auto sf = view->animationFactor();
                  QRectF targetRect(surfaceGeometry.topLeft() * sf, surfaceGeometry.size() * sf);
                  QMatrix4x4 targetTransform = QOpenGLTextureBlitter::targetTransform(targetRect, QRect(QPoint(), size()));
                  m_textureBlitter.blit(texture->textureId(), targetTransform, surfaceOrigin);
              }
          }
      }
      functions->glDisable(GL_BLEND);

      m_textureBlitter.release();
      m_compositor->endRender();
  }

  View *Window::viewAt(const QPointF &point)
  {
      View *ret = nullptr;
      Q_FOREACH (View *view, m_compositor->views()) {
          if (view == m_dragIconView)
              continue;
          QRectF geom(view->position(), view->size());
          if (geom.contains(point))
              ret = view;
      }
      return ret;
  }

  void Window::startMove()
  {
      m_grabState = MoveGrab;
  }

  void Window::startResize(int edge, bool anchored)
  {
      m_initialSize = m_mouseView->windowSize();
      m_grabState = ResizeGrab;
      m_resizeEdge = edge;
      m_resizeAnchored = anchored;
      m_resizeAnchorPosition = getAnchorPosition(m_mouseView->position(), edge, m_mouseView->surface()->size());
  }

  void Window::startDrag(View *dragIcon)
  {
      m_grabState = DragGrab;
      m_dragIconView = dragIcon;
      m_compositor->raise(dragIcon);
  }

  void Window::mousePressEvent(QMouseEvent *e)
  {
      if (mouseGrab())
          return;
      if (m_mouseView.isNull()) {
          m_mouseView = viewAt(e->localPos());
          if (!m_mouseView) {
              m_compositor->closePopups();
              return;
          }
          if (e->modifiers() == Qt::AltModifier || e->modifiers() == Qt::MetaModifier)
              m_grabState = MoveGrab; //start move
          else
              m_compositor->raise(m_mouseView);
          m_initialMousePos = e->localPos();
          m_mouseOffset = e->localPos() - m_mouseView->position();

          QMouseEvent moveEvent(QEvent::MouseMove, e->localPos(), e->globalPos(), Qt::NoButton, Qt::NoButton, e->modifiers());
          sendMouseEvent(&moveEvent, m_mouseView);
      }
      sendMouseEvent(e, m_mouseView);
  }

  void Window::mouseReleaseEvent(QMouseEvent *e)
  {
      if (!mouseGrab())
          sendMouseEvent(e, m_mouseView);
      if (e->buttons() == Qt::NoButton) {
          if (m_grabState == DragGrab) {
              View *view = viewAt(e->localPos());
              m_compositor->handleDrag(view, e);
          }
          m_mouseView = nullptr;
          m_grabState = NoGrab;
      }
  }

  void Window::mouseMoveEvent(QMouseEvent *e)
  {
      switch (m_grabState) {
      case NoGrab: {
          View *view = m_mouseView ? m_mouseView.data() : viewAt(e->localPos());
          sendMouseEvent(e, view);
          if (!view)
              setCursor(Qt::ArrowCursor);
      }
          break;
      case MoveGrab: {
          m_mouseView->setPosition(e->localPos() - m_mouseOffset);
          update();
      }
          break;
      case ResizeGrab: {
          QPoint delta = (e->localPos() - m_initialMousePos).toPoint();
          m_compositor->handleResize(m_mouseView, m_initialSize, delta, m_resizeEdge);
      }
          break;
      case DragGrab: {
          View *view = viewAt(e->localPos());
          m_compositor->handleDrag(view, e);
          if (m_dragIconView) {
              m_dragIconView->setPosition(e->localPos() + m_dragIconView->offset());
              update();
          }
      }
          break;
      }
  }

  void Window::sendMouseEvent(QMouseEvent *e, View *target)
  {
      QPointF mappedPos = e->localPos();
      if (target)
          mappedPos -= target->position();
      QMouseEvent viewEvent(e->type(), mappedPos, e->localPos(), e->button(), e->buttons(), e->modifiers());
      m_compositor->handleMouseEvent(target, &viewEvent);
  }

  void Window::keyPressEvent(QKeyEvent *e)
  {
      m_compositor->defaultSeat()->sendKeyPressEvent(e->nativeScanCode());
  }

  void Window::keyReleaseEvent(QKeyEvent *e)
  {
      m_compositor->defaultSeat()->sendKeyReleaseEvent(e->nativeScanCode());
  }