4 files changed, 37 insertions, 23 deletions
diff --git a/examples/opengl/qopenglwidget/bubble.cpp b/examples/opengl/qopenglwidget/bubble.cpp
index adf5742f6a..dbaf460f6f 100644
--- a/examples/opengl/qopenglwidget/bubble.cpp
+++ b/examples/opengl/qopenglwidget/bubble.cpp
@@ -109,10 +109,10 @@ void Bubble::drawBubble(QPainter *painter)
 
 QColor Bubble::randomColor()
 {
-    int red = int(185 + 70.0*qrand()/(RAND_MAX+1.0));
-    int green = int(185 + 70.0*qrand()/(RAND_MAX+1.0));
-    int blue = int(205 + 50.0*qrand()/(RAND_MAX+1.0));
-    int alpha = int(91 + 100.0*qrand()/(RAND_MAX+1.0));
+    int red = int(185 + QRandomGenerator::global()->bounded(70));
+    int green = int(185 + QRandomGenerator::global()->bounded(70));
+    int blue = int(205 + QRandomGenerator::global()->bounded(50));
+    int alpha = int(91 + QRandomGenerator::global()->bounded(100));
 
     return QColor(red, green, blue, alpha);
 }
diff --git a/examples/opengl/qopenglwidget/glwidget.cpp b/examples/opengl/qopenglwidget/glwidget.cpp
index 21d922d713..3fe919f94b 100644
--- a/examples/opengl/qopenglwidget/glwidget.cpp
+++ b/examples/opengl/qopenglwidget/glwidget.cpp
@@ -53,14 +53,19 @@
 #include <QPaintEngine>
 #include <QOpenGLShaderProgram>
 #include <QOpenGLTexture>
+#include <QRandomGenerator>
 #include <QCoreApplication>
-#include <math.h>
+#include <qmath.h>
 
 #include "mainwindow.h"
 #include "bubble.h"
 
 const int bubbleNum = 8;
 
+#ifndef GL_SRGB8_ALPHA8
+#define GL_SRGB8_ALPHA8 0x8C43
+#endif
+
 GLWidget::GLWidget(MainWindow *mw, bool button, const QColor &background)
     : m_mainWindow(mw),
       m_showBubbles(true),
@@ -75,6 +80,8 @@ GLWidget::GLWidget(MainWindow *mw, bool button, const QColor &background)
       m_background(background)
 {
     setMinimumSize(300, 250);
+    if (QCoreApplication::arguments().contains(QStringLiteral("--srgb")))
+        setTextureFormat(GL_SRGB8_ALPHA8);
 }
 
 GLWidget::~GLWidget()
@@ -414,11 +421,11 @@ void GLWidget::paintGL()
 void GLWidget::createBubbles(int number)
 {
     for (int i = 0; i < number; ++i) {
-        QPointF position(width()*(0.1 + (0.8*qrand()/(RAND_MAX+1.0))),
-                         height()*(0.1 + (0.8*qrand()/(RAND_MAX+1.0))));
-        qreal radius = qMin(width(), height())*(0.0175 + 0.0875*qrand()/(RAND_MAX+1.0));
-        QPointF velocity(width()*0.0175*(-0.5 + qrand()/(RAND_MAX+1.0)),
-                         height()*0.0175*(-0.5 + qrand()/(RAND_MAX+1.0)));
+        QPointF position(width()*(0.1 + QRandomGenerator::global()->bounded(0.8)),
+                         height()*(0.1 + QRandomGenerator::global()->bounded(0.8)));
+        qreal radius = qMin(width(), height())*(0.0175 + QRandomGenerator::global()->bounded(0.0875));
+        QPointF velocity(width()*0.0175*(-0.5 + QRandomGenerator::global()->bounded(1.0)),
+                         height()*0.0175*(-0.5 + QRandomGenerator::global()->bounded(1.0)));
 
         m_bubbles.append(new Bubble(position, radius, velocity));
     }
@@ -449,21 +456,21 @@ void GLWidget::createGeometry()
     extrude(x4, y4, y4, x4);
     extrude(y4, x4, y3, x3);
 
-    const qreal Pi = 3.14159f;
     const int NumSectors = 100;
+    const qreal sectorAngle = 2 * qreal(M_PI) / NumSectors;
 
     for (int i = 0; i < NumSectors; ++i) {
-        qreal angle1 = (i * 2 * Pi) / NumSectors;
-        qreal x5 = 0.30 * sin(angle1);
-        qreal y5 = 0.30 * cos(angle1);
-        qreal x6 = 0.20 * sin(angle1);
-        qreal y6 = 0.20 * cos(angle1);
-
-        qreal angle2 = ((i + 1) * 2 * Pi) / NumSectors;
-        qreal x7 = 0.20 * sin(angle2);
-        qreal y7 = 0.20 * cos(angle2);
-        qreal x8 = 0.30 * sin(angle2);
-        qreal y8 = 0.30 * cos(angle2);
+        qreal angle = i * sectorAngle;
+        qreal x5 = 0.30 * sin(angle);
+        qreal y5 = 0.30 * cos(angle);
+        qreal x6 = 0.20 * sin(angle);
+        qreal y6 = 0.20 * cos(angle);
+
+        angle += sectorAngle;
+        qreal x7 = 0.20 * sin(angle);
+        qreal y7 = 0.20 * cos(angle);
+        qreal x8 = 0.30 * sin(angle);
+        qreal y8 = 0.30 * cos(angle);
 
         quad(x5, y5, x6, y6, x7, y7, x8, y8);
 
diff --git a/examples/opengl/qopenglwidget/main.cpp b/examples/opengl/qopenglwidget/main.cpp
index ea90dca62f..42fc772445 100644
--- a/examples/opengl/qopenglwidget/main.cpp
+++ b/examples/opengl/qopenglwidget/main.cpp
@@ -69,11 +69,15 @@ int main( int argc, char ** argv )
     parser.addVersionOption();
     QCommandLineOption multipleSampleOption("multisample", "Multisampling");
     parser.addOption(multipleSampleOption);
+    QCommandLineOption srgbOption("srgb", "Use sRGB Color Space");
+    parser.addOption(srgbOption);
     parser.process(a);
 
     QSurfaceFormat format;
     format.setDepthBufferSize(24);
     format.setStencilBufferSize(8);
+    if (parser.isSet(srgbOption))
+        format.setColorSpace(QSurfaceFormat::sRGBColorSpace);
     if (parser.isSet(multipleSampleOption))
         format.setSamples(4);
     QSurfaceFormat::setDefaultFormat(format);
diff --git a/examples/opengl/qopenglwidget/mainwindow.cpp b/examples/opengl/qopenglwidget/mainwindow.cpp
index 1bb2aa2bf0..4bd123628f 100644
--- a/examples/opengl/qopenglwidget/mainwindow.cpp
+++ b/examples/opengl/qopenglwidget/mainwindow.cpp
@@ -56,6 +56,7 @@
 #include <QSlider>
 #include <QLabel>
 #include <QCheckBox>
+#include <QRandomGenerator>
 #include <QSpinBox>
 #include <QScrollArea>
 
@@ -155,7 +156,9 @@ void MainWindow::addNew()
 {
     if (m_nextY == 4)
         return;
-    GLWidget *w = new GLWidget(this, false, qRgb(qrand() % 256, qrand() % 256, qrand() % 256));
+    GLWidget *w = new GLWidget(this, false, qRgb(QRandomGenerator::global()->bounded(256),
+                                                 QRandomGenerator::global()->bounded(256),
+                                                 QRandomGenerator::global()->bounded(256)));
     m_glWidgets << w;
     connect(m_timer, &QTimer::timeout, w, QOverload<>::of(&QWidget::update));
     m_layout->addWidget(w, m_nextY, m_nextX, 1, 1);