Move titlebar drawing routines to QWasmWindow

The title bar drawing routines belong in QWasmWindow, not in the
compositor. This provides better encapsulation as many properties
don't have to be leaked from QWasmWindow. Extensibility will also
improve.

Change-Id: If73dd4e87602f62bff0de92e1405f89e7a9f3b43
Pick-to: 6.4
Reviewed-by: Morten Johan Sørvig <morten.sorvig@qt.io>

src/plugins/platforms/wasm/qwasmcompositor.cpp

@@ -2,7 +2,6 @@
 // SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GPL-3.0-only
 
 #include "qwasmcompositor.h"
-#include "qwasmstylepixmaps_p.h"
 #include "qwasmwindow.h"
 #include "qwasmeventtranslator.h"
 #include "qwasmeventdispatcher.h"
@@ -16,7 +15,6 @@
 #include <QtGui/qopenglfunctions.h>
 #include <QtGui/qoffscreensurface.h>
 #include <QtGui/qpainter.h>
-#include <private/qpixmapcache_p.h>
 
 #include <private/qguiapplication_p.h>
 
@@ -264,85 +262,6 @@ void QWasmCompositor::drawWindowContent(QOpenGLTextureBlitter *blitter, QWasmScr
     blit(blitter, screen, texture, windowCanvasGeometry);
 }
 
-QPalette QWasmCompositor::makeWindowPalette()
-{
-    QPalette palette;
-    palette.setColor(QPalette::Active, QPalette::Highlight,
-                     palette.color(QPalette::Active, QPalette::Highlight));
-    palette.setColor(QPalette::Active, QPalette::Base,
-                     palette.color(QPalette::Active, QPalette::Highlight));
-    palette.setColor(QPalette::Inactive, QPalette::Highlight,
-                     palette.color(QPalette::Inactive, QPalette::Dark));
-    palette.setColor(QPalette::Inactive, QPalette::Base,
-                     palette.color(QPalette::Inactive, QPalette::Dark));
-    palette.setColor(QPalette::Inactive, QPalette::HighlightedText,
-                     palette.color(QPalette::Inactive, QPalette::Window));
-
-    return palette;
-}
-
-QRect QWasmCompositor::titlebarRect(QWasmTitleBarOptions tb, QWasmCompositor::SubControls subcontrol)
-{
-    QRect ret;
-    const int controlMargin = 2;
-    const int controlHeight = tb.rect.height() - controlMargin *2;
-    const int delta = controlHeight + controlMargin;
-    int offset = 0;
-
-    bool isMinimized = tb.state & Qt::WindowMinimized;
-    bool isMaximized = tb.state & Qt::WindowMaximized;
-
-    ret = tb.rect;
-    switch (subcontrol) {
-    case SC_TitleBarLabel:
-        if (tb.flags & Qt::WindowSystemMenuHint)
-            ret.adjust(delta, 0, -delta, 0);
-        break;
-    case SC_TitleBarCloseButton:
-        if (tb.flags & Qt::WindowSystemMenuHint) {
-            ret.adjust(0, 0, -delta, 0);
-            offset += delta;
-        }
-        break;
-    case SC_TitleBarMaxButton:
-        if (!isMaximized && tb.flags & Qt::WindowMaximizeButtonHint) {
-            ret.adjust(0, 0, -delta*2, 0);
-            offset += (delta +delta);
-        }
-        break;
-    case SC_TitleBarNormalButton:
-        if (isMinimized && (tb.flags & Qt::WindowMinimizeButtonHint)) {
-            offset += delta;
-        } else if (isMaximized && (tb.flags & Qt::WindowMaximizeButtonHint)) {
-            ret.adjust(0, 0, -delta*2, 0);
-            offset += (delta +delta);
-        }
-        break;
-    case SC_TitleBarSysMenu:
-        if (tb.flags & Qt::WindowSystemMenuHint) {
-            ret.setRect(tb.rect.left() + controlMargin, tb.rect.top() + controlMargin,
-                        controlHeight, controlHeight);
-        }
-        break;
-    default:
-        break;
-    };
-
-    if (subcontrol != SC_TitleBarLabel && subcontrol != SC_TitleBarSysMenu) {
-        ret.setRect(tb.rect.right() - offset, tb.rect.top() + controlMargin,
-                    controlHeight, controlHeight);
-    }
-
-    if (qApp->layoutDirection() == Qt::LeftToRight)
-        return ret;
-
-    QRect rect = ret;
-    rect.translate(2 * (tb.rect.right() - ret.right()) +
-                   ret.width() - tb.rect.width(), 0);
-
-    return rect;
-}
-
 void QWasmCompositor::requestUpdateAllWindows()
 {
     m_requestUpdateAllWindows = true;
@@ -439,51 +358,6 @@ int dpiScaled(qreal value)
     return value * (qreal(qt_defaultDpiX()) / 96.0);
 }
 
-QWasmCompositor::QWasmTitleBarOptions QWasmCompositor::makeTitleBarOptions(const QWasmWindow *window)
-{
-    int width = window->windowFrameGeometry().width();
-    int border = window->borderWidth();
-
-    QWasmTitleBarOptions titleBarOptions;
-
-    titleBarOptions.rect = QRect(border, border, width - 2 * border, window->titleHeight());
-    titleBarOptions.flags = window->window()->flags();
-    titleBarOptions.state = window->window()->windowState();
-
-    bool isMaximized = titleBarOptions.state & Qt::WindowMaximized; // this gets reset when maximized
-
-    if (titleBarOptions.flags & (Qt::WindowTitleHint))
-        titleBarOptions.subControls |= SC_TitleBarLabel;
-    if (titleBarOptions.flags & Qt::WindowMaximizeButtonHint) {
-        if (isMaximized)
-            titleBarOptions.subControls |= SC_TitleBarNormalButton;
-        else
-            titleBarOptions.subControls |= SC_TitleBarMaxButton;
-    }
-    if (titleBarOptions.flags & Qt::WindowSystemMenuHint) {
-        titleBarOptions.subControls |= SC_TitleBarCloseButton;
-        titleBarOptions.subControls |= SC_TitleBarSysMenu;
-    }
-
-
-    titleBarOptions.palette = QWasmCompositor::makeWindowPalette();
-
-    if (window->window()->isActive())
-        titleBarOptions.palette.setCurrentColorGroup(QPalette::Active);
-    else
-        titleBarOptions.palette.setCurrentColorGroup(QPalette::Inactive);
-
-    if (window->activeSubControl() != QWasmCompositor::SC_None)
-        titleBarOptions.subControls = window->activeSubControl();
-
-    if (!window->window()->title().isEmpty())
-        titleBarOptions.titleBarOptionsString = window->window()->title();
-
-    titleBarOptions.windowIcon = window->window()->icon();
-
-    return titleBarOptions;
-}
-
 void QWasmCompositor::drawWindowDecorations(QOpenGLTextureBlitter *blitter, QWasmScreen *screen,
                                             const QWasmWindow *window)
 {
@@ -496,9 +370,7 @@ void QWasmCompositor::drawWindowDecorations(QOpenGLTextureBlitter *blitter, QWas
     QPainter painter(&image);
     painter.fillRect(QRect(0, 0, width, height), painter.background());
 
-    QWasmTitleBarOptions titleBarOptions = makeTitleBarOptions(window);
+    window->drawTitleBar(&painter);
-
-    drawTitlebarWindow(titleBarOptions, &painter);
 
     QWasmFrameOptions frameOptions;
     frameOptions.rect = QRect(0, 0, width, height);
@@ -572,109 +444,6 @@ void QWasmCompositor::drawFrameWindow(QWasmFrameOptions options, QPainter *paint
     painter->setPen(oldPen);
 }
 
-//from commonstyle.cpp
-static QPixmap cachedPixmapFromXPM(const char * const *xpm)
-{
-    QPixmap result;
-    const QString tag = QString::asprintf("xpm:0x%p", static_cast<const void*>(xpm));
-    if (!QPixmapCache::find(tag, &result)) {
-        result = QPixmap(xpm);
-        QPixmapCache::insert(tag, result);
-    }
-    return result;
-}
-
-void QWasmCompositor::drawItemPixmap(QPainter *painter, const QRect &rect, int alignment,
-                                      const QPixmap &pixmap) const
-{
-    qreal scale = pixmap.devicePixelRatio();
-    QSize size =  pixmap.size() / scale;
-    int x = rect.x();
-    int y = rect.y();
-    int w = size.width();
-    int h = size.height();
-    if ((alignment & Qt::AlignVCenter) == Qt::AlignVCenter)
-        y += rect.size().height()/2 - h/2;
-    else if ((alignment & Qt::AlignBottom) == Qt::AlignBottom)
-        y += rect.size().height() - h;
-    if ((alignment & Qt::AlignRight) == Qt::AlignRight)
-        x += rect.size().width() - w;
-    else if ((alignment & Qt::AlignHCenter) == Qt::AlignHCenter)
-        x += rect.size().width()/2 - w/2;
-
-    QRect aligned = QRect(x, y, w, h);
-    QRect inter = aligned.intersected(rect);
-
-    painter->drawPixmap(inter.x(), inter.y(), pixmap, inter.x() - aligned.x(),
-                        inter.y() - aligned.y(), inter.width() * scale, inter.height() *scale);
-}
-
-
-void QWasmCompositor::drawTitlebarWindow(QWasmTitleBarOptions tb, QPainter *painter)
-{
-    QRect ir;
-    if (tb.subControls.testFlag(SC_TitleBarLabel)) {
-        QColor left = tb.palette.highlight().color();
-        QColor right = tb.palette.base().color();
-
-        QBrush fillBrush(left);
-        if (left != right) {
-            QPoint p1(tb.rect.x(), tb.rect.top() + tb.rect.height()/2);
-            QPoint p2(tb.rect.right(), tb.rect.top() + tb.rect.height()/2);
-            QLinearGradient lg(p1, p2);
-            lg.setColorAt(0, left);
-            lg.setColorAt(1, right);
-            fillBrush = lg;
-        }
-
-        painter->fillRect(tb.rect, fillBrush);
-        ir = titlebarRect(tb, SC_TitleBarLabel);
-        painter->setPen(tb.palette.highlightedText().color());
-        painter->drawText(ir.x() + 2, ir.y(), ir.width() - 2, ir.height(),
-                          Qt::AlignLeft | Qt::AlignVCenter | Qt::TextSingleLine, tb.titleBarOptionsString);
-    } // SC_TitleBarLabel
-
-    QPixmap pixmap;
-
-    if (tb.subControls.testFlag(SC_TitleBarCloseButton)
-            && tb.flags & Qt::WindowSystemMenuHint) {
-        ir = titlebarRect(tb, SC_TitleBarCloseButton);
-        pixmap = cachedPixmapFromXPM(qt_close_xpm).scaled(QSize(10, 10));
-        drawItemPixmap(painter, ir, Qt::AlignCenter, pixmap);
-    } //SC_TitleBarCloseButton
-
-    if (tb.subControls.testFlag(SC_TitleBarMaxButton)
-            && tb.flags & Qt::WindowMaximizeButtonHint
-            && !(tb.state & Qt::WindowMaximized)) {
-        ir = titlebarRect(tb, SC_TitleBarMaxButton);
-        pixmap = cachedPixmapFromXPM(qt_maximize_xpm).scaled(QSize(10, 10));
-        drawItemPixmap(painter, ir, Qt::AlignCenter, pixmap);
-    } //SC_TitleBarMaxButton
-
-    bool drawNormalButton = (tb.subControls & SC_TitleBarNormalButton)
-            && (((tb.flags & Qt::WindowMinimizeButtonHint)
-                 && (tb.flags & Qt::WindowMinimized))
-                || ((tb.flags & Qt::WindowMaximizeButtonHint)
-                    && (tb.flags & Qt::WindowMaximized)));
-
-    if (drawNormalButton) {
-        ir = titlebarRect(tb, SC_TitleBarNormalButton);
-        pixmap = cachedPixmapFromXPM(qt_normalizeup_xpm).scaled( QSize(10, 10));
-
-        drawItemPixmap(painter, ir, Qt::AlignCenter, pixmap);
-    } // SC_TitleBarNormalButton
-
-    if (tb.subControls & SC_TitleBarSysMenu && tb.flags & Qt::WindowSystemMenuHint) {
-        ir = titlebarRect(tb, SC_TitleBarSysMenu);
-        if (!tb.windowIcon.isNull()) {
-            tb.windowIcon.paint(painter, ir, Qt::AlignCenter);
-        } else {
-            pixmap = cachedPixmapFromXPM(qt_menu_xpm).scaled(QSize(10, 10));
-            drawItemPixmap(painter, ir, Qt::AlignCenter, pixmap);
-        }
-    }
-}
-
 void QWasmCompositor::drawWindow(QOpenGLTextureBlitter *blitter, QWasmScreen *screen,
                                  const QWasmWindow *window)
 {

src/plugins/platforms/wasm/qwasmcompositor.h

@@ -41,17 +41,6 @@ public:
     void deregisterEventHandlers();
     void destroy();
 
-    enum QWasmSubControl {
-        SC_None =                  0x00000000,
-        SC_TitleBarSysMenu =       0x00000001,
-        SC_TitleBarMinButton =     0x00000002,
-        SC_TitleBarMaxButton =     0x00000004,
-        SC_TitleBarCloseButton =   0x00000008,
-        SC_TitleBarNormalButton =  0x00000010,
-        SC_TitleBarLabel =         0x00000100
-    };
-    Q_DECLARE_FLAGS(SubControls, QWasmSubControl)
-
     enum QWasmStateFlag {
         State_None =               0x00000000,
         State_Enabled =            0x00000001,
@@ -60,16 +49,6 @@ public:
     };
     Q_DECLARE_FLAGS(StateFlags, QWasmStateFlag)
 
-    struct QWasmTitleBarOptions {
-        QRect rect;
-        Qt::WindowFlags flags;
-        int state;
-        QPalette palette;
-        QString titleBarOptionsString;
-        QWasmCompositor::SubControls subControls;
-        QIcon windowIcon;
-    };
-
     struct QWasmFrameOptions {
         QRect rect;
         int lineWidth;
@@ -90,9 +69,6 @@ public:
     QWindow *windowAt(QPoint globalPoint, int padding = 0) const;
     QWindow *keyWindow() const;
 
-    static QWasmTitleBarOptions makeTitleBarOptions(const QWasmWindow *window);
-    static QRect titlebarRect(QWasmTitleBarOptions tb, QWasmCompositor::SubControls subcontrol);
-
     QWasmScreen *screen();
     QOpenGLContext *context();
 
@@ -166,12 +142,7 @@ private:
     void drawWindowDecorations(QOpenGLTextureBlitter *blitter, QWasmScreen *screen,
                                const QWasmWindow *window);
 
-    static QPalette makeWindowPalette();
-
     void drawFrameWindow(QWasmFrameOptions options, QPainter *painter);
-    void drawTitlebarWindow(QWasmTitleBarOptions options, QPainter *painter);
-    void drawItemPixmap(QPainter *painter, const QRect &rect,
-                                    int alignment, const QPixmap &pixmap) const;
 
     static int keyboard_cb(int eventType, const EmscriptenKeyboardEvent *keyEvent, void *userData);
     static int focus_cb(int eventType, const EmscriptenFocusEvent *focusEvent, void *userData);
@@ -220,7 +191,6 @@ private:
     bool m_mouseInCanvas = false;
     QPointer<QWindow> m_windowUnderMouse;
 };
-Q_DECLARE_OPERATORS_FOR_FLAGS(QWasmCompositor::SubControls)
 
 QT_END_NAMESPACE
 

src/plugins/platforms/wasm/qwasmwindow.cpp

@@ -6,9 +6,11 @@
 #include <QtGui/private/qopenglcontext_p.h>
 #include <QtGui/private/qwindow_p.h>
 #include <QtGui/qopenglcontext.h>
+#include <private/qpixmapcache_p.h>
 
 #include "qwasmwindow.h"
 #include "qwasmscreen.h"
+#include "qwasmstylepixmaps_p.h"
 #include "qwasmcompositor.h"
 #include "qwasmeventdispatcher.h"
 
@@ -19,6 +21,61 @@ QT_BEGIN_NAMESPACE
 
 Q_GUI_EXPORT int qt_defaultDpiX();
 
+namespace {
+// from commonstyle.cpp
+static QPixmap cachedPixmapFromXPM(const char *const *xpm)
+{
+    QPixmap result;
+    const QString tag = QString::asprintf("xpm:0x%p", static_cast<const void *>(xpm));
+    if (!QPixmapCache::find(tag, &result)) {
+        result = QPixmap(xpm);
+        QPixmapCache::insert(tag, result);
+    }
+    return result;
+}
+
+QPalette makePalette()
+{
+    QPalette palette;
+    palette.setColor(QPalette::Active, QPalette::Highlight,
+                     palette.color(QPalette::Active, QPalette::Highlight));
+    palette.setColor(QPalette::Active, QPalette::Base,
+                     palette.color(QPalette::Active, QPalette::Highlight));
+    palette.setColor(QPalette::Inactive, QPalette::Highlight,
+                     palette.color(QPalette::Inactive, QPalette::Dark));
+    palette.setColor(QPalette::Inactive, QPalette::Base,
+                     palette.color(QPalette::Inactive, QPalette::Dark));
+    palette.setColor(QPalette::Inactive, QPalette::HighlightedText,
+                     palette.color(QPalette::Inactive, QPalette::Window));
+
+    return palette;
+}
+
+void drawItemPixmap(QPainter *painter, const QRect &rect, int alignment, const QPixmap &pixmap)
+{
+    qreal scale = pixmap.devicePixelRatio();
+    QSize size = pixmap.size() / scale;
+    int x = rect.x();
+    int y = rect.y();
+    int w = size.width();
+    int h = size.height();
+    if ((alignment & Qt::AlignVCenter) == Qt::AlignVCenter)
+        y += rect.size().height() / 2 - h / 2;
+    else if ((alignment & Qt::AlignBottom) == Qt::AlignBottom)
+        y += rect.size().height() - h;
+    if ((alignment & Qt::AlignRight) == Qt::AlignRight)
+        x += rect.size().width() - w;
+    else if ((alignment & Qt::AlignHCenter) == Qt::AlignHCenter)
+        x += rect.size().width() / 2 - w / 2;
+
+    QRect aligned = QRect(x, y, w, h);
+    QRect inter = aligned.intersected(rect);
+
+    painter->drawPixmap(inter.x(), inter.y(), pixmap, inter.x() - aligned.x(),
+                        inter.y() - aligned.y(), inter.width() * scale, inter.height() * scale);
+}
+}
+
 QWasmWindow::QWasmWindow(QWindow *w, QWasmCompositor *compositor, QWasmBackingStore *backingStore)
     : QPlatformWindow(w),
       m_window(w),
@@ -162,14 +219,16 @@ void QWasmWindow::injectMousePressed(const QPoint &local, const QPoint &global,
     if (!hasTitleBar() || button != Qt::LeftButton)
         return;
 
-    if (maxButtonRect().contains(global))
+    const auto pointInFrameCoords = global - windowFrameGeometry().topLeft();
-        m_activeControl = QWasmCompositor::SC_TitleBarMaxButton;
+    const auto options = makeTitleBarOptions();
-    else if (minButtonRect().contains(global))
+    if (getTitleBarControlRect(options, SC_TitleBarMaxButton).contains(pointInFrameCoords))
-        m_activeControl = QWasmCompositor::SC_TitleBarMinButton;
+        m_activeControl = SC_TitleBarMaxButton;
-    else if (closeButtonRect().contains(global))
+    else if (getTitleBarControlRect(options, SC_TitleBarMinButton).contains(pointInFrameCoords))
-        m_activeControl = QWasmCompositor::SC_TitleBarCloseButton;
+        m_activeControl = SC_TitleBarMinButton;
-    else if (normButtonRect().contains(global))
+    else if (getTitleBarControlRect(options, SC_TitleBarCloseButton).contains(pointInFrameCoords))
-        m_activeControl = QWasmCompositor::SC_TitleBarNormalButton;
+        m_activeControl = SC_TitleBarCloseButton;
+    else if (getTitleBarControlRect(options, SC_TitleBarNormalButton).contains(pointInFrameCoords))
+        m_activeControl = SC_TitleBarNormalButton;
 
     invalidate();
 }
@@ -183,20 +242,25 @@ void QWasmWindow::injectMouseReleased(const QPoint &local, const QPoint &global,
     if (!hasTitleBar() || button != Qt::LeftButton)
         return;
 
-    if (closeButtonRect().contains(global) && m_activeControl == QWasmCompositor::SC_TitleBarCloseButton) {
+    const auto pointInFrameCoords = global - windowFrameGeometry().topLeft();
+    const auto options = makeTitleBarOptions();
+    if (getTitleBarControlRect(options, SC_TitleBarCloseButton).contains(pointInFrameCoords)
+        && m_activeControl == SC_TitleBarCloseButton) {
         window()->close();
         return;
     }
 
-    if (maxButtonRect().contains(global) && m_activeControl == QWasmCompositor::SC_TitleBarMaxButton) {
+    if (getTitleBarControlRect(options, SC_TitleBarMaxButton).contains(pointInFrameCoords)
+        && m_activeControl == SC_TitleBarMaxButton) {
         window()->setWindowState(Qt::WindowMaximized);
     }
 
-    if (normButtonRect().contains(global) && m_activeControl == QWasmCompositor::SC_TitleBarNormalButton) {
+    if (getTitleBarControlRect(options, SC_TitleBarNormalButton).contains(pointInFrameCoords)
+        && m_activeControl == SC_TitleBarNormalButton) {
         window()->setWindowState(Qt::WindowNoState);
     }
 
-    m_activeControl = QWasmCompositor::SC_None;
+    m_activeControl = SC_None;
 
     invalidate();
 }
@@ -265,48 +329,75 @@ Qt::Edges QWasmWindow::resizeEdgesAtPoint(QPoint point) const
     return edges | (right.contains(point) ? Qt::Edge::RightEdge : Qt::Edge(0));
 }
 
-QRect getSubControlRect(const QWasmWindow *window, QWasmCompositor::SubControls subControl)
+QRect QWasmWindow::getTitleBarControlRect(const TitleBarOptions &tb, TitleBarControl control) const
 {
-    QWasmCompositor::QWasmTitleBarOptions options = QWasmCompositor::makeTitleBarOptions(window);
+    QRect ret;
+    const int controlMargin = 2;
+    const int controlHeight = tb.rect.height() - controlMargin * 2;
+    const int delta = controlHeight + controlMargin;
+    int offset = 0;
 
-    QRect r = QWasmCompositor::titlebarRect(options, subControl);
+    bool isMinimized = tb.state & Qt::WindowMinimized;
-    r.translate(window->window()->frameGeometry().x(), window->window()->frameGeometry().y());
+    bool isMaximized = tb.state & Qt::WindowMaximized;
 
-    return r;
+    ret = tb.rect;
-}
+    switch (control) {
+    case SC_TitleBarLabel:
+        if (tb.flags & Qt::WindowSystemMenuHint)
+            ret.adjust(delta, 0, -delta, 0);
+        break;
+    case SC_TitleBarCloseButton:
+        if (tb.flags & Qt::WindowSystemMenuHint) {
+            ret.adjust(0, 0, -delta, 0);
+            offset += delta;
+        }
+        break;
+    case SC_TitleBarMaxButton:
+        if (!isMaximized && tb.flags & Qt::WindowMaximizeButtonHint) {
+            ret.adjust(0, 0, -delta * 2, 0);
+            offset += (delta + delta);
+        }
+        break;
+    case SC_TitleBarNormalButton:
+        if (isMinimized && (tb.flags & Qt::WindowMinimizeButtonHint)) {
+            offset += delta;
+        } else if (isMaximized && (tb.flags & Qt::WindowMaximizeButtonHint)) {
+            ret.adjust(0, 0, -delta * 2, 0);
+            offset += (delta + delta);
+        }
+        break;
+    case SC_TitleBarSysMenu:
+        if (tb.flags & Qt::WindowSystemMenuHint) {
+            ret.setRect(tb.rect.left() + controlMargin, tb.rect.top() + controlMargin,
+                        controlHeight, controlHeight);
+        }
+        break;
+    default:
+        break;
+    };
 
-QRect QWasmWindow::maxButtonRect() const
+    if (control != SC_TitleBarLabel && control != SC_TitleBarSysMenu) {
-{
+        ret.setRect(tb.rect.right() - offset, tb.rect.top() + controlMargin, controlHeight,
-    return getSubControlRect(this, QWasmCompositor::SC_TitleBarMaxButton);
+                    controlHeight);
-}
+    }
 
-QRect QWasmWindow::minButtonRect() const
+    if (qApp->layoutDirection() == Qt::LeftToRight)
-{
+        return ret;
-    return getSubControlRect(this, QWasmCompositor::SC_TitleBarMinButton);
-}
 
-QRect QWasmWindow::closeButtonRect() const
+    QRect rect = ret;
-{
+    rect.translate(2 * (tb.rect.right() - ret.right()) + ret.width() - tb.rect.width(), 0);
-    return getSubControlRect(this, QWasmCompositor::SC_TitleBarCloseButton);
-}
 
-QRect QWasmWindow::normButtonRect() const
+    return rect;
-{
-    return getSubControlRect(this, QWasmCompositor::SC_TitleBarNormalButton);
-}
-
-QRect QWasmWindow::sysMenuRect() const
-{
-    return getSubControlRect(this, QWasmCompositor::SC_TitleBarSysMenu);
 }
 
 QRegion QWasmWindow::titleControlRegion() const
 {
     QRegion result;
-    result += closeButtonRect();
+    const auto options = makeTitleBarOptions();
-    result += minButtonRect();
+    result += getTitleBarControlRect(options, SC_TitleBarCloseButton);
-    result += maxButtonRect();
+    result += getTitleBarControlRect(options, SC_TitleBarMinButton);
-    result += sysMenuRect();
+    result += getTitleBarControlRect(options, SC_TitleBarMaxButton);
+    result += getTitleBarControlRect(options, SC_TitleBarSysMenu);
 
     return result;
 }
@@ -316,7 +407,7 @@ void QWasmWindow::invalidate()
     m_compositor->requestUpdateWindow(this);
 }
 
-QWasmCompositor::SubControls QWasmWindow::activeSubControl() const
+QWasmWindow::TitleBarControl QWasmWindow::activeTitleBarControl() const
 {
     return m_activeControl;
 }
@@ -366,6 +457,114 @@ void QWasmWindow::applyWindowState()
     setGeometry(newGeom);
 }
 
+void QWasmWindow::drawTitleBar(QPainter *painter) const
+{
+    const auto tb = makeTitleBarOptions();
+    QRect ir;
+    if (tb.subControls.testFlag(SC_TitleBarLabel)) {
+        QColor left = tb.palette.highlight().color();
+        QColor right = tb.palette.base().color();
+
+        QBrush fillBrush(left);
+        if (left != right) {
+            QPoint p1(tb.rect.x(), tb.rect.top() + tb.rect.height() / 2);
+            QPoint p2(tb.rect.right(), tb.rect.top() + tb.rect.height() / 2);
+            QLinearGradient lg(p1, p2);
+            lg.setColorAt(0, left);
+            lg.setColorAt(1, right);
+            fillBrush = lg;
+        }
+
+        painter->fillRect(tb.rect, fillBrush);
+        ir = getTitleBarControlRect(tb, SC_TitleBarLabel);
+        painter->setPen(tb.palette.highlightedText().color());
+        painter->drawText(ir.x() + 2, ir.y(), ir.width() - 2, ir.height(),
+                          Qt::AlignLeft | Qt::AlignVCenter | Qt::TextSingleLine,
+                          tb.titleBarOptionsString);
+    } // SC_TitleBarLabel
+
+    QPixmap pixmap;
+
+    if (tb.subControls.testFlag(SC_TitleBarCloseButton) && tb.flags & Qt::WindowSystemMenuHint) {
+        ir = getTitleBarControlRect(tb, SC_TitleBarCloseButton);
+        pixmap = cachedPixmapFromXPM(qt_close_xpm).scaled(QSize(10, 10));
+        drawItemPixmap(painter, ir, Qt::AlignCenter, pixmap);
+    } // SC_TitleBarCloseButton
+
+    if (tb.subControls.testFlag(SC_TitleBarMaxButton) && tb.flags & Qt::WindowMaximizeButtonHint
+        && !(tb.state & Qt::WindowMaximized)) {
+        ir = getTitleBarControlRect(tb, SC_TitleBarMaxButton);
+        pixmap = cachedPixmapFromXPM(qt_maximize_xpm).scaled(QSize(10, 10));
+        drawItemPixmap(painter, ir, Qt::AlignCenter, pixmap);
+    } // SC_TitleBarMaxButton
+
+    bool drawNormalButton = (tb.subControls & SC_TitleBarNormalButton)
+            && (((tb.flags & Qt::WindowMinimizeButtonHint) && (tb.flags & Qt::WindowMinimized))
+                || ((tb.flags & Qt::WindowMaximizeButtonHint) && (tb.flags & Qt::WindowMaximized)));
+
+    if (drawNormalButton) {
+        ir = getTitleBarControlRect(tb, SC_TitleBarNormalButton);
+        pixmap = cachedPixmapFromXPM(qt_normalizeup_xpm).scaled(QSize(10, 10));
+
+        drawItemPixmap(painter, ir, Qt::AlignCenter, pixmap);
+    } // SC_TitleBarNormalButton
+
+    if (tb.subControls & SC_TitleBarSysMenu && tb.flags & Qt::WindowSystemMenuHint) {
+        ir = getTitleBarControlRect(tb, SC_TitleBarSysMenu);
+        if (!tb.windowIcon.isNull()) {
+            tb.windowIcon.paint(painter, ir, Qt::AlignCenter);
+        } else {
+            pixmap = cachedPixmapFromXPM(qt_menu_xpm).scaled(QSize(10, 10));
+            drawItemPixmap(painter, ir, Qt::AlignCenter, pixmap);
+        }
+    }
+}
+
+QWasmWindow::TitleBarOptions QWasmWindow::makeTitleBarOptions() const
+{
+    int width = windowFrameGeometry().width();
+    int border = borderWidth();
+
+    TitleBarOptions titleBarOptions;
+
+    titleBarOptions.rect = QRect(border, border, width - 2 * border, titleHeight());
+    titleBarOptions.flags = window()->flags();
+    titleBarOptions.state = window()->windowState();
+
+    bool isMaximized =
+            titleBarOptions.state & Qt::WindowMaximized; // this gets reset when maximized
+
+    if (titleBarOptions.flags & (Qt::WindowTitleHint))
+        titleBarOptions.subControls |= SC_TitleBarLabel;
+    if (titleBarOptions.flags & Qt::WindowMaximizeButtonHint) {
+        if (isMaximized)
+            titleBarOptions.subControls |= SC_TitleBarNormalButton;
+        else
+            titleBarOptions.subControls |= SC_TitleBarMaxButton;
+    }
+    if (titleBarOptions.flags & Qt::WindowSystemMenuHint) {
+        titleBarOptions.subControls |= SC_TitleBarCloseButton;
+        titleBarOptions.subControls |= SC_TitleBarSysMenu;
+    }
+
+    titleBarOptions.palette = makePalette();
+
+    if (window()->isActive())
+        titleBarOptions.palette.setCurrentColorGroup(QPalette::Active);
+    else
+        titleBarOptions.palette.setCurrentColorGroup(QPalette::Inactive);
+
+    if (activeTitleBarControl() != SC_None)
+        titleBarOptions.subControls = activeTitleBarControl();
+
+    if (!window()->title().isEmpty())
+        titleBarOptions.titleBarOptionsString = window()->title();
+
+    titleBarOptions.windowIcon = window()->icon();
+
+    return titleBarOptions;
+}
+
 QRect QWasmWindow::normalGeometry() const
 {
     return m_normalGeometry;

src/plugins/platforms/wasm/qwasmwindow.h

@@ -16,6 +16,17 @@ QT_BEGIN_NAMESPACE
 class QWasmWindow : public QPlatformWindow
 {
 public:
+    enum TitleBarControl {
+        SC_None = 0x00000000,
+        SC_TitleBarSysMenu = 0x00000001,
+        SC_TitleBarMinButton = 0x00000002,
+        SC_TitleBarMaxButton = 0x00000004,
+        SC_TitleBarCloseButton = 0x00000008,
+        SC_TitleBarNormalButton = 0x00000010,
+        SC_TitleBarLabel = 0x00000100
+    };
+    Q_DECLARE_FLAGS(TitleBarControls, TitleBarControl);
+
     QWasmWindow(QWindow *w, QWasmCompositor *compositor, QWasmBackingStore *backingStore);
     ~QWasmWindow();
     void destroy();
@@ -47,41 +58,53 @@ public:
     void injectMouseReleased(const QPoint &local, const QPoint &global,
                             Qt::MouseButton button, Qt::KeyboardModifiers mods);
 
-    int titleHeight() const;
-    int borderWidth() const;
-    QRegion titleGeometry() const;
-    QRegion resizeRegion() const;
     bool isPointOnTitle(QPoint point) const;
     bool isPointOnResizeRegion(QPoint point) const;
+
     Qt::Edges resizeEdgesAtPoint(QPoint point) const;
-    QRect maxButtonRect() const;
-    QRect minButtonRect() const;
-    QRect closeButtonRect() const;
-    QRect sysMenuRect() const;
-    QRect normButtonRect() const;
-    QRegion titleControlRegion() const;
-    QWasmCompositor::SubControls activeSubControl() const;
 
     void setWindowState(Qt::WindowStates state) override;
     void applyWindowState();
     bool setKeyboardGrabEnabled(bool) override { return false; }
     bool setMouseGrabEnabled(bool) override { return false; }
 
+    void drawTitleBar(QPainter *painter) const;
+
 protected:
     void invalidate();
     bool hasTitleBar() const;
 
-protected:
+private:
     friend class QWasmScreen;
 
-    QWindow* m_window = nullptr;
+    struct TitleBarOptions
+    {
+        QRect rect;
+        Qt::WindowFlags flags;
+        int state;
+        QPalette palette;
+        QString titleBarOptionsString;
+        TitleBarControls subControls;
+        QIcon windowIcon;
+    };
+
+    TitleBarOptions makeTitleBarOptions() const;
+    QRect getTitleBarControlRect(const TitleBarOptions &tb, TitleBarControl control) const;
+    QRegion titleControlRegion() const;
+    QRegion titleGeometry() const;
+    int borderWidth() const;
+    int titleHeight() const;
+    QRegion resizeRegion() const;
+    TitleBarControl activeTitleBarControl() const;
+
+    QWindow *m_window = nullptr;
     QWasmCompositor *m_compositor = nullptr;
     QWasmBackingStore *m_backingStore = nullptr;
     QRect m_normalGeometry {0, 0, 0 ,0};
 
     Qt::WindowStates m_windowState = Qt::WindowNoState;
     Qt::WindowStates m_previousWindowState = Qt::WindowNoState;
-    QWasmCompositor::SubControls m_activeControl = QWasmCompositor::SC_None;
+    TitleBarControl m_activeControl = SC_None;
     WId m_winid = 0;
     bool m_hasTitle = false;
     bool m_needsCompositor = false;
@@ -90,5 +113,7 @@ protected:
     friend class QWasmEventTranslator;
     bool windowIsPopupType(Qt::WindowFlags flags) const;
 };
+
+Q_DECLARE_OPERATORS_FOR_FLAGS(QWasmWindow::TitleBarControls);
 QT_END_NAMESPACE
 #endif // QWASMWINDOW_H