File indexing completed on 2024-05-12 04:19:38

 /*
  * SPDX-FileCopyrightText: 2021 Arjen Hiemstra <ahiemstra@heimr.nl>
  *
  * SPDX-License-Identifier: LGPL-2.1-or-later
  */
 
 #include "alphabackgrounditem.h"
 
 #include <QApplication>
 #include <QPainter>
 
 using namespace Gwenview;
 
 AlphaBackgroundItem::AlphaBackgroundItem(AbstractImageView *parent)
     : QGraphicsItem(parent)
     , mParent(parent)
 {
 }
 
 AlphaBackgroundItem::~AlphaBackgroundItem() = default;
 
 AbstractImageView::AlphaBackgroundMode AlphaBackgroundItem::mode() const
 {
     return mMode;
 }
 
 void Gwenview::AlphaBackgroundItem::setMode(AbstractImageView::AlphaBackgroundMode mode)
 {
     if (mode == mMode) {
         return;
     }
 
     mMode = mode;
     update();
 }
 
 QColor AlphaBackgroundItem::color()
 {
     return mColor;
 }
 
 void AlphaBackgroundItem::setColor(const QColor &color)
 {
     if (color == mColor) {
         return;
     }
 
     mColor = color;
     update();
 }
 
 void AlphaBackgroundItem::paint(QPainter *painter, const QStyleOptionGraphicsItem * /*option*/, QWidget * /*widget*/)
 {
     // We need to floor the image size. Unfortunately, QPointF and QSizeF both
     // _round_ when converting instead of flooring. This means that we need to
     // manually do the flooring here, because we otherwise run into pixel
     // alignment issues with the image that is drawn on top of the background.
     const auto width = int((mParent->documentSize().width() / qApp->devicePixelRatio()) * mParent->zoom());
     const auto height = int((mParent->documentSize().height() / qApp->devicePixelRatio()) * mParent->zoom());
     const auto imageRect = QRectF{mParent->imageOffset().toPoint(), QSize{width, height}};
 
     switch (mMode) {
     case AbstractImageView::AlphaBackgroundNone:
         // No background, do not paint anything.
         break;
     case AbstractImageView::AlphaBackgroundCheckBoard: {
         if (!mCheckBoardTexture) {
             createCheckBoardTexture();
         }
 
         painter->drawTiledPixmap(imageRect, *mCheckBoardTexture, mParent->scrollPos());
         break;
     }
     case AbstractImageView::AlphaBackgroundSolid:
         painter->fillRect(imageRect, mColor);
         break;
     default:
         break;
     }
 }
 
 QRectF AlphaBackgroundItem::boundingRect() const
 {
     return mParent->boundingRect();
 }
 
 void AlphaBackgroundItem::createCheckBoardTexture()
 {
     mCheckBoardTexture = std::make_unique<QPixmap>(32, 32);
     QPainter painter(mCheckBoardTexture.get());
     painter.fillRect(mCheckBoardTexture->rect(), QColor(128, 128, 128));
     const QColor light = QColor(192, 192, 192);
     painter.fillRect(0, 0, 16, 16, light);
     painter.fillRect(16, 16, 16, 16, light);
     // Don't set the pixmap's devicePixelRatio, just let Qt take care of scaling
     // this, otherwise we get some ugly glitches.
 }