Not displayed elements by glDrawElements function in QOpenGLWidget

I want to integrate a particle system in my app on QOpenGLWIdget. I have one thing - Magic Particle by Astralax. I integrate functions of this framework in my app, but I don't see anything on the screen. I don't understand what the problem is. I try to change any params of QOpenGLContext, but nothing work. paintDevice->paint() is calling glDrawElements. What could reason of this problem?

You can all code on GitHub.

mainwidget.cpp

Code:

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void MainWidget::initializeGL()
{
    makeCurrent();
    initializeOpenGLFunctions();
    glClearColor(0, 0, 0, 1);
 
    m_paintDevice = new PaintDevice(this->width(), this->height());
    timer.start(12, this);
}
 
void MainWidget::timerEvent(QTimerEvent *e)
{
    m_paintDevice->update();
    update();
}
 
void MainWidget::paintGL()
{
    glClearColor(0.0f, 0.0f, 0.0f, 1.0f);
    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
    m_paintDevice->paint();
    QCoreApplication::postEvent(this, new QEvent(QEvent::UpdateRequest));
}

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mp_wrap.cpp

Code:

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void MP_Device_WRAP::DrawVertices(int starting_index, int indexes_count, int max_vertices)
{
    MP_BUFFER_RAM *index_buffer_ram = (MP_BUFFER_RAM *)index_buffer;
 
#ifdef INDEX_BUFFER_32_WRAP
    glDrawElements(GL_TRIANGLES, indexes_count, GL_UNSIGNED_INT, &(index_buffer_ram->buffer[starting_index * 4]));
#else
    glDrawElements(GL_TRIANGLES, indexes_count, GL_UNSIGNED_SHORT, &(index_buffer_ram->buffer[starting_index * 2]));
#endif
}

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