better fps counter

Qt_Performance_Benchmark/FpsItem.qml

@@ -1,59 +0,0 @@
-import QtQuick 2.0
-import QtQuick.Window 2.2
-
-Rectangle {
-    id: root
-    property int frameCounter: 0
-    property int frameCounterAvg: 0
-    property int counter: 0
-    property int fps: 0
-    property int fpsAvg: 0
-
-    readonly property real dp: Screen.pixelDensity * 25.4/160
-
-    color: "black"
-    width:  childrenRect.width + 10*dp;
-    height: childrenRect.height + 10*dp;
-
-    Image {
-        id: spinnerImage
-        anchors.verticalCenter: parent.verticalCenter
-        x: 4 * dp
-        width: 36 * dp
-        height: width
-        source: "images/spinner.png"
-        NumberAnimation on rotation {
-            from:0
-            to: 360
-            duration: 800
-            loops: Animation.Infinite
-        }
-        onRotationChanged: frameCounter++;
-    }
-
-    Text {
-        anchors.left: spinnerImage.right
-        anchors.leftMargin: 8 * dp
-        anchors.verticalCenter: spinnerImage.verticalCenter
-        color: "#c0c0c0"
-        font.pixelSize: 18 * dp
-        text: "Ø " + root.fpsAvg + " | " + root.fps + " fps"
-    }
-
-    Timer {
-        interval: 2000
-        repeat: true
-        running: true
-        onTriggered: {
-            frameCounterAvg += frameCounter;
-            root.fps = frameCounter/2;
-            counter++;
-            frameCounter = 0;
-            if (counter >= 3) {
-                root.fpsAvg = frameCounterAvg/(2*counter)
-                frameCounterAvg = 0;
-                counter = 0;
-            }
-        }
-    }
-}

Qt_Performance_Benchmark/Qt_Performance_Benchmark.pro

@@ -7,6 +7,7 @@ CONFIG += c++11
 #DEFINES += QT_DISABLE_DEPRECATED_BEFORE=0x060000    # disables all the APIs deprecated before Qt 6.0.0
 
 SOURCES += \
+        frequencymonitor.cpp \
         main.cpp
 
 RESOURCES += qml.qrc
@@ -21,3 +22,6 @@ QML_DESIGNER_IMPORT_PATH =
 qnx: target.path = /tmp/$${TARGET}/bin
 else: unix:!android: target.path = /opt/$${TARGET}/bin
 !isEmpty(target.path): INSTALLS += target
+
+HEADERS += \
+    frequencymonitor.h

Qt_Performance_Benchmark/frequencymonitor.cpp

@@ -0,0 +1,65 @@
+#include "frequencymonitor.h"
+#include <QQuickWindow>
+
+FrequencyMonitor::FrequencyMonitor(QQuickItem *parent) :
+    QQuickItem(parent),
+    m_counter(0),
+    m_refreshPeriod(1000)
+{
+    connect(this, &FrequencyMonitor::windowChanged, this, &FrequencyMonitor::handleWindowChanged);
+}
+
+int FrequencyMonitor::fps() const
+{
+    return m_fps;
+}
+
+void FrequencyMonitor::setFps(int fps)
+{
+    if (m_fps == fps)
+        return;
+
+    m_fps = fps;
+    emit fpsChanged();
+}
+
+int FrequencyMonitor::refreshPeriod() const
+{
+    return m_refreshPeriod;
+}
+
+void FrequencyMonitor::setRefreshPeriod(int msec)
+{
+    if (m_refreshPeriod == msec)
+        return;
+
+    m_refreshPeriod = msec;
+    emit refreshPeriodChanged();
+}
+
+void FrequencyMonitor::handleAfterRendering()
+{
+    const int elapsedMsec = m_time.elapsed();
+
+    m_counter++;
+
+    if (elapsedMsec >= m_refreshPeriod)
+    {
+        setFps(m_counter / (elapsedMsec / 1000.0));
+
+        m_counter = 0;
+        m_time.restart();
+    }
+}
+
+void FrequencyMonitor::handleWindowChanged(QQuickWindow *window)
+{
+    if (m_windowConnection)
+        this->disconnect(m_windowConnection);
+
+    if (window)
+    {
+        m_time.restart();
+        m_windowConnection = connect(window, &QQuickWindow::afterRendering, this, &FrequencyMonitor::handleAfterRendering);
+    }
+}

Qt_Performance_Benchmark/frequencymonitor.h

@@ -0,0 +1,42 @@
+#ifndef FREQUENCYMONITOR_H
+#define FREQUENCYMONITOR_H
+
+#include <QQuickItem>
+#include <QTime>
+#include <QMetaObject>
+
+class QQuickWindow;
+
+class FrequencyMonitor : public QQuickItem
+{
+    Q_OBJECT
+    Q_PROPERTY(int fps READ fps NOTIFY fpsChanged)
+    Q_PROPERTY(int refreshPeriod READ refreshPeriod WRITE setRefreshPeriod NOTIFY refreshPeriodChanged)
+public:
+    explicit FrequencyMonitor(QQuickItem *parent = 0);
+
+    int fps() const;
+    void setFps(int fps);
+
+    // by default refresh one time per 1000 msec
+    int refreshPeriod() const;
+    void setRefreshPeriod(int msec);
+
+signals:
+    void fpsChanged();
+    void refreshPeriodChanged();
+
+public slots:
+    void handleAfterRendering();
+    void handleWindowChanged(QQuickWindow * window);
+
+protected:
+    QMetaObject::Connection m_windowConnection;
+    QTime m_time;
+    int m_fps;
+    int m_counter;
+    int m_refreshPeriod;
+
+};
+
+#endif // FREQUENCYMONITOR_H

Qt_Performance_Benchmark/main.cpp

@@ -1,12 +1,18 @@
 #include <QGuiApplication>
 #include <QQmlApplicationEngine>
+#include "frequencymonitor.h"
+
+
+
 
 int main(int argc, char *argv[])
 {
     QCoreApplication::setAttribute(Qt::AA_EnableHighDpiScaling);
 
     QGuiApplication app(argc, argv);
-
+    
+    qmlRegisterType<FrequencyMonitor>("be.mindgoo.tools", 0, 1, "FrequencyMonitor");
+    
     QQmlApplicationEngine engine;
     const QUrl url(QStringLiteral("qrc:/main.qml"));
     QObject::connect(&engine, &QQmlApplicationEngine::objectCreated,

Qt_Performance_Benchmark/main.qml

@@ -1,6 +1,7 @@
 import QtQuick 2.12
 import QtQuick.Window 2.12
 import QtQuick.Controls 2.3
+import be.mindgoo.tools 0.1
 
 
 Window {
@@ -54,13 +55,14 @@ Window {
         onClicked: rootwin.onChecked(checked)
     }
 
-    FpsItem {
-        id: fpsItem
-        anchors.verticalCenterOffset: 106
-           anchors.horizontalCenterOffset: -239
-           anchors.centerIn: parent
+    FrequencyMonitor {
+           id: monitor
+           refreshPeriod: 500
        }
 
+       Text {
+           text: monitor.fps
+       }
 }
 
 /*##^##

Qt_Performance_Benchmark/qml.qrc

@@ -1,6 +1,5 @@
 <RCC>
     <qresource prefix="/">
         <file>main.qml</file>
-        <file>FpsItem.qml</file>
     </qresource>
 </RCC>