File indexing completed on 2024-05-19 16:34:48

 /*
     KWin - the KDE window manager
     This file is part of the KDE project.
 
     SPDX-FileCopyrightText: 2013 Martin Gräßlin <mgraesslin@kde.org>
 
     SPDX-License-Identifier: GPL-2.0-or-later
 */
 #include "workspacescene_qpainter.h"
 // KWin
 #include "decorations/decoratedclient.h"
 #include "scene/itemrenderer_qpainter.h"
 #include "window.h"
 
 // Qt
 #include <KDecoration2/Decoration>
 #include <QDebug>
 #include <QPainter>
 
 #include <cmath>
 
 namespace KWin
 {
 
 //****************************************
 // SceneQPainter
 //****************************************
 
 WorkspaceSceneQPainter::WorkspaceSceneQPainter(QPainterBackend *backend)
     : WorkspaceScene(std::make_unique<ItemRendererQPainter>())
     , m_backend(backend)
 {
 }
 
 WorkspaceSceneQPainter::~WorkspaceSceneQPainter()
 {
 }
 
 std::unique_ptr<Shadow> WorkspaceSceneQPainter::createShadow(Window *window)
 {
     return std::make_unique<SceneQPainterShadow>(window);
 }
 
 DecorationRenderer *WorkspaceSceneQPainter::createDecorationRenderer(Decoration::DecoratedClientImpl *impl)
 {
     return new SceneQPainterDecorationRenderer(impl);
 }
 
 //****************************************
 // QPainterShadow
 //****************************************
 SceneQPainterShadow::SceneQPainterShadow(Window *window)
     : Shadow(window)
 {
 }
 
 SceneQPainterShadow::~SceneQPainterShadow()
 {
 }
 
 bool SceneQPainterShadow::prepareBackend()
 {
     return true;
 }
 
 //****************************************
 // QPainterDecorationRenderer
 //****************************************
 SceneQPainterDecorationRenderer::SceneQPainterDecorationRenderer(Decoration::DecoratedClientImpl *client)
     : DecorationRenderer(client)
 {
 }
 
 QImage SceneQPainterDecorationRenderer::image(SceneQPainterDecorationRenderer::DecorationPart part) const
 {
     Q_ASSERT(part != DecorationPart::Count);
     return m_images[int(part)];
 }
 
 void SceneQPainterDecorationRenderer::render(const QRegion &region)
 {
     if (areImageSizesDirty()) {
         resizeImages();
         resetImageSizesDirty();
     }
 
     auto imageSize = [this](DecorationPart part) {
         return m_images[int(part)].size() / m_images[int(part)].devicePixelRatio();
     };
 
     const QRect top(QPoint(0, 0), imageSize(DecorationPart::Top));
     const QRect left(QPoint(0, top.height()), imageSize(DecorationPart::Left));
     const QRect right(QPoint(top.width() - imageSize(DecorationPart::Right).width(), top.height()), imageSize(DecorationPart::Right));
     const QRect bottom(QPoint(0, left.y() + left.height()), imageSize(DecorationPart::Bottom));
 
     const QRect geometry = region.boundingRect();
     auto renderPart = [this](const QRect &rect, const QRect &partRect, int index) {
         if (rect.isEmpty()) {
             return;
         }
         QPainter painter(&m_images[index]);
         painter.setRenderHint(QPainter::Antialiasing);
         painter.setWindow(QRect(partRect.topLeft(), partRect.size() * effectiveDevicePixelRatio()));
         painter.setClipRect(rect);
         painter.save();
         // clear existing part
         painter.setCompositionMode(QPainter::CompositionMode_Source);
         painter.fillRect(rect, Qt::transparent);
         painter.restore();
         client()->decoration()->paint(&painter, rect);
     };
 
     renderPart(left.intersected(geometry), left, int(DecorationPart::Left));
     renderPart(top.intersected(geometry), top, int(DecorationPart::Top));
     renderPart(right.intersected(geometry), right, int(DecorationPart::Right));
     renderPart(bottom.intersected(geometry), bottom, int(DecorationPart::Bottom));
 }
 
 void SceneQPainterDecorationRenderer::resizeImages()
 {
     QRectF left, top, right, bottom;
     client()->window()->layoutDecorationRects(left, top, right, bottom);
 
     auto checkAndCreate = [this](int index, const QSizeF &size) {
         auto dpr = effectiveDevicePixelRatio();
         if (m_images[index].size() != size * dpr || m_images[index].devicePixelRatio() != dpr) {
             m_images[index] = QImage(size.toSize() * dpr, QImage::Format_ARGB32_Premultiplied);
             m_images[index].setDevicePixelRatio(dpr);
             m_images[index].fill(Qt::transparent);
         }
     };
     checkAndCreate(int(DecorationPart::Left), left.size());
     checkAndCreate(int(DecorationPart::Right), right.size());
     checkAndCreate(int(DecorationPart::Top), top.size());
     checkAndCreate(int(DecorationPart::Bottom), bottom.size());
 }
 
 } // KWin