Doc: Compile OpenGL snippets

Fix minor issues (e.g. whitespace, missing semi-colon) in passing.

Change-Id: I022ac0382ae1068a75246964c37532e7e15417b0
Done-with: Nico Vertriest <nico.vertriest@qt.io>
Task-number: QTBUG-81486
Reviewed-by: Topi Reiniö <topi.reinio@qt.io>

src/gui/doc/snippets/code/code.pro

@@ -21,4 +21,7 @@ SOURCES = \
     src_gui_kernel_qguiapplication_x11.cpp \
     src_gui_kernel_qkeysequence.cpp \
     src_gui_kernel_qshortcutmap.cpp \
-    src_gui_math3d_qquaternion.cpp
+    src_gui_math3d_qquaternion.cpp \
+    src_gui_opengl_qopenglbuffer.cpp \
+    src_gui_opengl_qopengldebug.cpp \
+    src_gui_opengl_qopenglfunctions.cpp

src/gui/doc/snippets/code/src_gui_opengl_qopenglbuffer.cpp

@@ -47,14 +47,22 @@
 ** $QT_END_LICENSE$
 **
 ****************************************************************************/
+#include <QtOpenGL/QOpenGLBuffer>
+
+namespace src_gui_opengl_qopenglbuffer {
+void wrapper() {
 
 //! [0]
-    QOpenGLBuffer buffer1(QOpenGLBuffer::IndexBuffer);
-    buffer1.create();
+QOpenGLBuffer buffer1(QOpenGLBuffer::IndexBuffer);
+buffer1.create();
 
-    QOpenGLBuffer buffer2 = buffer1;
+QOpenGLBuffer buffer2 = buffer1;
 //! [0]
 
+
 //! [1]
-    QOpenGLBuffer::release(QOpenGLBuffer::VertexBuffer);
+QOpenGLBuffer::release(QOpenGLBuffer::VertexBuffer);
 //! [1]
+
+} // wrapper
+} // src_gui_opengl_qopenglbuffer

src/gui/doc/snippets/code/src_gui_opengl_qopengldebug.cpp

@@ -47,54 +47,87 @@
 ** $QT_END_LICENSE$
 **
 ****************************************************************************/
+#include <QOpenGLContext>
+#include <QSurfaceFormat>
+#include <QWidget>
+#include <QtOpenGL/QOpenGLDebugLogger>
+
+namespace src_gui_opengl_qopengldebug {
+struct LogHandler : public QObject
+{
+    Q_OBJECT
+public slots:
+    static bool handleLoggedMessage() { return true; };
+};
+struct SnippetWrapper : public QObject
+{
+    Q_OBJECT
+    void wrapper1(LogHandler *receiver);
+    const QWidget *receiver;
+};
+
+void wrapper0() {
 
 //! [0]
-    GLenum error = GL_NO_ERROR;
-    do {
-        error = glGetError();
-        if (error != GL_NO_ERROR)
-            // handle the error
-    } while (error != GL_NO_ERROR);
+GLenum error = GL_NO_ERROR;
+do {
+    error = glGetError();
+    if (error != GL_NO_ERROR) {
+        // handle the error
+    }
+} while (error != GL_NO_ERROR);
 //! [0]
 
-//! [1]
-    QSurfaceFormat format;
-    // asks for a OpenGL 3.2 debug context using the Core profile
-    format.setMajorVersion(3);
-    format.setMinorVersion(2);
-    format.setProfile(QSurfaceFormat::CoreProfile);
-    format.setOption(QSurfaceFormat::DebugContext);
 
-    QOpenGLContext *context = new QOpenGLContext;
-    context->setFormat(format);
-    context->create();
+//! [1]
+QSurfaceFormat format;
+// asks for a OpenGL 3.2 debug context using the Core profile
+format.setMajorVersion(3);
+format.setMinorVersion(2);
+format.setProfile(QSurfaceFormat::CoreProfile);
+format.setOption(QSurfaceFormat::DebugContext);
+
+QOpenGLContext *context = new QOpenGLContext;
+context->setFormat(format);
+context->create();
 //! [1]
 
-//! [2]
-    QOpenGLContext *ctx = QOpenGLContext::currentContext();
-    QOpenGLDebugLogger *logger = new QOpenGLDebugLogger(this);
+} // wrapper0
 
-    logger->initialize(); // initializes in the current context, i.e. ctx
+
+void SnippetWrapper::wrapper1(LogHandler *receiver) {
+//! [2]
+QOpenGLContext *ctx = QOpenGLContext::currentContext();
+QOpenGLDebugLogger *logger = new QOpenGLDebugLogger(this);
+
+logger->initialize(); // initializes in the current context, i.e. ctx
 //! [2]
 
+
 //! [3]
-    ctx->hasExtension(QByteArrayLiteral("GL_KHR_debug"))
+ctx->hasExtension(QByteArrayLiteral("GL_KHR_debug"));
 //! [3]
 
+
 //! [4]
-    const QList<QOpenGLDebugMessage> messages = logger->loggedMessages();
-    for (const QOpenGLDebugMessage &message : messages)
-        qDebug() << message;
+const QList<QOpenGLDebugMessage> messages = logger->loggedMessages();
+for (const QOpenGLDebugMessage &message : messages)
+    qDebug() << message;
 //! [4]
 
+
 //! [5]
-    connect(logger, &QOpenGLDebugLogger::messageLogged, receiver, &LogHandler::handleLoggedMessage);
-    logger->startLogging();
+connect(logger, &QOpenGLDebugLogger::messageLogged, receiver, &LogHandler::handleLoggedMessage);
+logger->startLogging();
 //! [5]
 
-//! [6]
-    QOpenGLDebugMessage message =
-        QOpenGLDebugMessage::createApplicationMessage(QStringLiteral("Custom message"));
 
-    logger->logMessage(message);
 //! [6]
+QOpenGLDebugMessage message =
+    QOpenGLDebugMessage::createApplicationMessage(QStringLiteral("Custom message"));
+
+logger->logMessage(message);
+//! [6]
+
+} // SnippetWrapper::wrapper1
+} // src_gui_opengl_qopengldebug

src/gui/doc/snippets/code/src_gui_opengl_qopenglfunctions.cpp

@@ -47,66 +47,87 @@
 ** $QT_END_LICENSE$
 **
 ****************************************************************************/
+#include <QOpenGLFunctions>
+#include <QtOpenGL/QOpenGLWindow>
+
+#include <QSurface>
+#include <QWidget>
+#include <QWindow>
+
+namespace src_gui_opengl_qopenglfunctions {
 
 //! [0]
-    class MyGLWindow : public QWindow, protected QOpenGLFunctions
-    {
-        Q_OBJECT
-    public:
-        explicit MyGLWindow(QScreen *screen = nullptr);
+class MyGLWindow : public QWindow, protected QOpenGLFunctions
+{
+    Q_OBJECT
+public:
+    explicit MyGLWindow(QScreen *screen = nullptr);
 
-    protected:
-        void initializeGL();
-        void paintGL();
+protected:
+    void initializeGL();
+    void paintGL();
 
-        QOpenGLContext *m_context;
-    };
+    QOpenGLContext *m_context;
+};
 
-    MyGLWindow(QScreen *screen)
-      : QWindow(screen), QOpenGLWidget(parent)
-    {
-        setSurfaceType(OpenGLSurface);
-        create();
+MyGLWindow::MyGLWindow(QScreen *screen)
+  : QWindow(screen)
+{
+    setSurfaceType(OpenGLSurface);
+    create();
 
-        // Create an OpenGL context
-        m_context = new QOpenGLContext;
-        m_context->create();
+    // Create an OpenGL context
+    m_context = new QOpenGLContext;
+    m_context->create();
 
-        // Setup scene and render it
-        initializeGL();
-        paintGL();
-    }
+    // Setup scene and render it
+    initializeGL();
+    paintGL();
+};
 
-    void MyGLWindow::initializeGL()
-    {
-        m_context->makeCurrent(this);
-        initializeOpenGLFunctions();
-    }
+void MyGLWindow::initializeGL()
+{
+    m_context->makeCurrent(this);
+    initializeOpenGLFunctions();
+}
 //! [0]
 
+
+int textureId = 0;
+
 //! [1]
-    void MyGLWindow::paintGL()
-    {
-        m_context->makeCurrent(this);
-        glActiveTexture(GL_TEXTURE1);
-        glBindTexture(GL_TEXTURE_2D, textureId);
-        ...
-        m_context->swapBuffers(this);
-        m_context->doneCurrent();
-    }
+void MyGLWindow::paintGL()
+{
+    m_context->makeCurrent(this);
+    glActiveTexture(GL_TEXTURE1);
+    glBindTexture(GL_TEXTURE_2D, textureId);
+    // ...
+    m_context->swapBuffers(this);
+    m_context->doneCurrent();
+}
 //! [1]
 
-//! [2]
-    QOpenGLFunctions glFuncs(QOpenGLContext::currentContext());
-    glFuncs.glActiveTexture(GL_TEXTURE1);
-//! [2]
 
+void wrapper0() {
+//! [2]
+QOpenGLFunctions glFuncs(QOpenGLContext::currentContext());
+glFuncs.glActiveTexture(GL_TEXTURE1);
+//! [2]
+} // wrapper0
+
+
+void wrapper1() {
 //! [3]
-    QOpenGLFunctions *glFuncs = QOpenGLContext::currentContext()->functions();
-    glFuncs->glActiveTexture(GL_TEXTURE1);
+QOpenGLFunctions *glFuncs = QOpenGLContext::currentContext()->functions();
+glFuncs->glActiveTexture(GL_TEXTURE1);
 //! [3]
 
+
 //! [4]
-    QOpenGLFunctions funcs(QOpenGLContext::currentContext());
-    bool npot = funcs.hasOpenGLFeature(QOpenGLFunctions::NPOTTextures);
+QOpenGLFunctions funcs(QOpenGLContext::currentContext());
+bool npot = funcs.hasOpenGLFeature(QOpenGLFunctions::NPOTTextures);
 //! [4]
+
+Q_UNUSED(npot);
+} // wrapper1
+} // src_gui_opengl_qopenglfunctions