Drawing a triangle doesn't work on laptop Asus K53SV with Mesa using Qt 6.7.0 beta1

The example below should draw a red triangle but it draws nothing. It prints: OpenGL version, GLSL version, and vendor:

```
OpenGL Version: 3.0 Mesa 11.2.2
GLSL Version: 1.30
OpenGL Vendor: VMware, Inc.
```

main.cpp

```

#include <QtGui/QOpenGLFunctions>
#include <QtGui/QSurfaceFormat>
#include <QtOpenGLWidgets/QOpenGLWidget>
#include <QtOpenGL/QOpenGLBuffer>
#include <QtOpenGL/QOpenGLShaderProgram>
#include <QtWidgets/QApplication>

class OpenGLWidget : public QOpenGLWidget, private QOpenGLFunctions
{
public:
    OpenGLWidget()
   

{         resize(350, 350);         setWindowTitle("OpenGL Triangle");     }

private:
    void initializeGL() override
    {
        initializeOpenGLFunctions();
        glClearColor(0.4f, 0.8f, 0.9f, 1.f);

        qDebug() << "OpenGL Version:" << (const char*) glGetString(GL_VERSION);
        qDebug() << "GLSL Version:" << (const char*) glGetString(GL_SHADING_LANGUAGE_VERSION);
        qDebug() << "OpenGL Vendor:" << (const char*) glGetString(GL_VENDOR);

        QString vertexShaderSource =
            "attribute vec2 aPosition;\n"
            "void main()\n"
            "

{\n"             "    gl_Position = vec4(aPosition, 0.0, 1.0);\n"             "}

\n";

        QString fragmentShaderSource =
            "#ifdef GL_ES\n"
            "precision mediump float;\n"
            "#endif\n"
            "//out vec4 fragColor;\n"
            "void main()\n"
            "

{\n"             "    gl_FragColor = vec4(1.0, 0.0, 0.0, 1.0);\n"             "}

\n";

        m_program.create();
        m_program.addShaderFromSourceCode(QOpenGLShader::ShaderTypeBit::Vertex,
                                          vertexShaderSource);
        m_program.addShaderFromSourceCode(QOpenGLShader::ShaderTypeBit::Fragment,
                                          fragmentShaderSource);
        m_program.link();
        m_program.bind();

        float vertPositions[] =

{             -0.5f, -0.5f,             0.5f, -0.5f,             0.f, 0.5f         }

;
        m_vertPosBuffer.create();
        m_vertPosBuffer.bind();
        m_vertPosBuffer.allocate(vertPositions, sizeof(vertPositions));
        m_program.setAttributeBuffer("aPosition", GL_FLOAT, 0, 2);
        m_program.enableAttributeArray("aPosition");
    }

    void paintGL() override
   

{         glClear(GL_COLOR_BUFFER_BIT);         glDrawArrays(GL_TRIANGLES, 0, 4);     }

private:
    QOpenGLShaderProgram m_program;
    QOpenGLBuffer m_vertPosBuffer;
};

int main(int argc, char *argv[])

{     QApplication app(argc, argv);     OpenGLWidget w;     w.show();     return app.exec(); }

```

pro

```

QT += core gui openglwidgets widgets

win32: LIBS += -lopengl32

CONFIG = c+17

SOURCES += \
    main.cpp
```

I can active the integrated video card instead of Mesa by adding the `AA_UseDesktopOpenGL` attribute:

```

int main(int argc, char *argv[])
{
    QApplication::setAttribute(Qt::ApplicationAttribute::AA_UseDesktopOpenGL);

```

The example above prints an info about the integrated card now:

```

OpenGL Version: 3.1.0 - Build 9.17.10.4459
GLSL Version: 1.40 - Intel Build 9.17.10.4459
OpenGL Vendor: Intel
```

But a triangle is white instead of red:

To active the discrete video card I should add these lines of code to main.cpp for GeForce and Radeon:

```
#ifdef _WIN32
#include <windows.h>
extern "C" __declspec(dllexport) DWORD NvOptimusEnablement = 0x00000001;
extern "C" __declspec(dllexport) DWORD AmdPowerXpressRequestHighPerformance = 0x00000001;
#endif
```

It prints this info:

```
OpenGL Version: 4.6.0 NVIDIA 391.35
GLSL Version: 4.60 NVIDIAOpenGL
Vendor: NVIDIA Corporation
```
But a triangle is still white.

Topic: https://forum.qt.io/topic/153686/drawing-a-triangle-doesn-t-work-on-laptop-asus-k53sv-with-mesa-using-qt-6-7-0-beta1