Scaling QOpenGLWidget

Vitek

Why does scaling work with no matter that i turned glViewport in resizeGL or not?

Window::Window(QWidget *parent, Qt::WindowFlags f) : QOpenGLWidget(parent, f)
{

}

void Window::initializeGL()
{
    QOpenGLFunctions_1_5 *f = QOpenGLContext::currentContext()->versionFunctions<QOpenGLFunctions_1_5>();
    f->glClearColor(.0f, .0f, .0f, .0f);
    f->glShadeModel(GL_FLAT);

}

void Window::resizeGL(int w, int h)
{
    QOpenGLFunctions_1_5 *f = QOpenGLContext::currentContext()->versionFunctions<QOpenGLFunctions_1_5>();
  //  f->glViewport(0, 0, 1000, 1000);
}

void Window::paintGL()
{
    QOpenGLFunctions_1_5 *f = QOpenGLContext::currentContext()->versionFunctions<QOpenGLFunctions_1_5>();
    f->glClear(GL_COLOR_BUFFER_BIT);
    f->glColor3f (1.0, 1.0, 1.0);
    f->glBegin(GL_POLYGON);
       f->glVertex2f(0.0, 0.0);
       f->glVertex2f(0.0, 0.5);
       f->glVertex2f(0.5, 0.5);
       f->glVertex2f(0.5, 0.0);
    f->glEnd();
    f->glFlush();
}

yoavmil

@Vitek said:

glViewport

try changing your clearColor to some thing other than black, see what happens.
f->glClearColor(.5f, .5f, .5f, 1.0f);

Vitek

Background color changed. It is all. If change glViewport, for example as f->glViewport(0, 0, 2000, 2000); that nothing happened.

SGaist

Hi,

It's a little bit more complex than that. See this article about the various transformation that you can apply.