Advance Wayland and KDE package bring-up

Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-openagent)

Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>

local/recipes/kde/kf6-kwindowsystem/source/tests/backgroundcontrasttest.cpp

@@ -0,0 +1,237 @@
+/*
+    This file is part of the KDE libraries
+    SPDX-FileCopyrightText: 2013 Nicolás Alvarez <nicolas.alvarez@gmail.com>
+
+    SPDX-License-Identifier: LGPL-2.1-or-later
+*/
+
+#include <optional>
+
+#include <QApplication>
+#include <QColorDialog>
+#include <QDebug>
+#include <QPaintEvent>
+#include <QPainter>
+#include <QPushButton>
+#include <QScopeGuard>
+#include <QSlider>
+#include <QVBoxLayout>
+#include <QWidget>
+
+#include <kwindoweffects.h>
+
+class ContrastTestWindow : public QWidget
+{
+public:
+    ContrastTestWindow();
+
+    void resizeEvent(QResizeEvent *) override;
+
+private:
+    QPushButton *m_btnNothing;
+    QPushButton *m_btnFullWindow;
+    QPushButton *m_btnRect;
+    QPushButton *m_btnEllipse;
+
+    QPushButton *m_blur;
+    bool m_doBlur;
+
+    QPushButton *m_bg;
+    QColor m_bgColour;
+
+    QSlider *m_contSlider;
+    QSlider *m_intSlider;
+    QSlider *m_satSlider;
+    QWidget *m_area;
+
+    qreal m_contrast;
+    qreal m_intensity;
+    qreal m_saturation;
+
+    enum { Nothing, FullWindow, Rect, Ellipse } m_state;
+
+    void disableContrast();
+    void enableContrast();
+    void enableContrastRect();
+    void enableContrastEllipse();
+    void updateContrast(int contrast);
+    void updateIntensity(int contrast);
+    void updateSaturation(int contrast);
+    void update();
+
+    void paintEvent(QPaintEvent *event) override
+    {
+        Q_UNUSED(event)
+
+        QPainter p(this);
+        p.setPen(Qt::transparent);
+        p.setBrush(m_bgColour);
+        p.drawRect(this->rect());
+
+        QWidget::paintEvent(event);
+    }
+};
+
+ContrastTestWindow::ContrastTestWindow()
+{
+    m_state = Nothing;
+    m_contrast = 1;
+    m_intensity = 1;
+    m_saturation = 1;
+    m_bgColour = Qt::transparent;
+    setAttribute(Qt::WA_TranslucentBackground);
+    setAttribute(Qt::WA_NoSystemBackground, true);
+
+    m_btnNothing = new QPushButton("Nothing");
+    m_btnFullWindow = new QPushButton("Full window");
+    m_btnRect = new QPushButton("Rectangle");
+    m_btnEllipse = new QPushButton("Ellipse");
+    m_blur = new QPushButton("Enable Blur");
+    m_blur->setCheckable(true);
+    m_bg = new QPushButton("Set Background Colour...");
+    connect(m_bg, &QPushButton::pressed, this, [this]() {
+        m_bgColour = QColorDialog::getColor(Qt::white, nullptr, "pick colour", QColorDialog::ShowAlphaChannel);
+
+        repaint();
+    });
+
+    connect(m_blur, &QPushButton::toggled, this, [this](bool checked) {
+        m_blur->setText(checked ? "Disable Blur" : "Enable Blur");
+        m_doBlur = checked;
+
+        update();
+    });
+
+    m_contSlider = new QSlider();
+    m_contSlider->setMaximum(200);
+    m_contSlider->setValue(100);
+    m_contSlider->setOrientation(Qt::Horizontal);
+
+    m_intSlider = new QSlider();
+    m_intSlider->setMaximum(200);
+    m_intSlider->setValue(100);
+    m_intSlider->setOrientation(Qt::Horizontal);
+
+    m_satSlider = new QSlider();
+    m_satSlider->setMaximum(200);
+    m_satSlider->setValue(100);
+    m_satSlider->setOrientation(Qt::Horizontal);
+
+    m_area = new QWidget;
+    m_area->setSizePolicy(QSizePolicy::Expanding, QSizePolicy::Expanding);
+
+    connect(m_btnNothing, &QPushButton::clicked, this, &ContrastTestWindow::disableContrast);
+    connect(m_btnFullWindow, &QPushButton::clicked, this, &ContrastTestWindow::enableContrast);
+    connect(m_btnRect, &QPushButton::clicked, this, &ContrastTestWindow::enableContrastRect);
+    connect(m_btnEllipse, &QPushButton::clicked, this, &ContrastTestWindow::enableContrastEllipse);
+
+    connect(m_contSlider, &QSlider::valueChanged, this, &ContrastTestWindow::updateContrast);
+    connect(m_intSlider, &QSlider::valueChanged, this, &ContrastTestWindow::updateIntensity);
+    connect(m_satSlider, &QSlider::valueChanged, this, &ContrastTestWindow::updateSaturation);
+
+    QVBoxLayout *layout = new QVBoxLayout(this);
+    layout->addWidget(m_btnNothing);
+    layout->addWidget(m_btnFullWindow);
+    layout->addWidget(m_btnRect);
+    layout->addWidget(m_btnEllipse);
+    layout->addWidget(m_contSlider);
+    layout->addWidget(m_intSlider);
+    layout->addWidget(m_satSlider);
+    layout->addWidget(m_area);
+    layout->addWidget(m_blur);
+    layout->addWidget(m_bg);
+
+    winId(); // force creation of the associated window
+}
+
+void ContrastTestWindow::update()
+{
+    const auto s = qScopeGuard([this]() {
+        repaint();
+    });
+
+    if (m_state == Nothing) {
+        KWindowEffects::enableBackgroundContrast(windowHandle(), false);
+        KWindowEffects::enableBlurBehind(windowHandle(), false);
+    }
+
+    auto region = QRegion();
+    switch (m_state) {
+    case Nothing:
+    case FullWindow:
+        break;
+    case Rect:
+        region = m_area->geometry();
+        break;
+    case Ellipse:
+        region = QRegion(m_area->geometry(), QRegion::Ellipse);
+        break;
+    }
+
+    KWindowEffects::enableBlurBehind(windowHandle(), m_doBlur, region);
+
+    KWindowEffects::enableBackgroundContrast(windowHandle(), true, m_contrast, m_intensity, m_saturation, region);
+
+    repaint();
+}
+
+void ContrastTestWindow::disableContrast()
+{
+    m_state = Nothing;
+
+    update();
+}
+void ContrastTestWindow::enableContrast()
+{
+    m_state = FullWindow;
+
+    update();
+}
+void ContrastTestWindow::enableContrastRect()
+{
+    m_state = Rect;
+
+    update();
+}
+void ContrastTestWindow::enableContrastEllipse()
+{
+    m_state = Ellipse;
+
+    update();
+}
+
+void ContrastTestWindow::updateContrast(int contrast)
+{
+    m_contrast = (qreal)contrast / 100;
+
+    update();
+}
+
+void ContrastTestWindow::updateIntensity(int contrast)
+{
+    m_intensity = (qreal)contrast / 100;
+
+    update();
+}
+
+void ContrastTestWindow::updateSaturation(int contrast)
+{
+    m_saturation = (qreal)contrast / 100;
+
+    update();
+}
+
+void ContrastTestWindow::resizeEvent(QResizeEvent *)
+{
+    update();
+}
+
+int main(int argc, char **argv)
+{
+    QApplication app(argc, argv);
+
+    ContrastTestWindow wnd;
+    wnd.show();
+
+    return app.exec();
+}