glBegin(GL_POLYGON);

        glColor3f(1.f, 0.f, 0.f);
        glVertex3f(-1.2f, -0.4f, 0.f);
        glColor3f(0.f, 1.f, 0.f);
        glVertex3f(0.6f, -0.4f, 0.f);
        glColor3f(0.f, 0.f, 1.f);
        glVertex3f(0.f, 0.6f, 0.f);

        glColor3f(1.f, 1.f, 1.f);
        glVertex3f(0.0f, 0.0f, 0.0f);

        glEnd();