hi!.
I'm using Qt 4.6 in GNU/Linux. i'm working with QGLWidget with kind of easiness but i've a problem when i want to change the color of the Lines.
I've tried all the combinations that i could think.
i've put the glColor after and befor de glBegin, use the qglColor, and glColor3f (and others glColors functions). But always it's a random color between blue and green (never red (i don't know why)).
What am i missing?

Qt Code: 
  1. glBegin(GL_LINES);
  2.     glColor3f(1.0f,0.0,0.0);
  3.      glVertex2f(50,1);
  4.      glVertex2f(120,1);
  5.   glEnd()
  6. ;
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this very basic code doesn't work

Qt Code: 
  1. void Plot::paintGL()
  2. {
  3.     glBegin(GL_LINES);
  4.     glColor3f(1.0f,0.0,0.0);
  5.      glVertex2f(50,1);
  6.  
  7.      glVertex2f(120,1);
  8.     glEnd();
  9. }
  10.  
  11. void Plot::initializeGL()
  12. {
  13.   // Also i've tried a lot of combinations here. GL_FLAT and others.
  14.     glClearColor(1.0, 1.0 , 1.0, 0.0);
  15.     glLoadIdentity();
  16.     glTranslatef(0,0.0,0);
  17.     glDisable(GL_TEXTURE_2D);
  18.     glDisable(GL_LIGHTING);
  19.     glShadeModel(GL_SMOOTH);
  20.  
  21. }
  22.  
  23.  
  24. void Plot::resizeGL(int w, int h)
  25. {
  26.     glViewport( 0, 0, (GLint)w, (GLint)h );
  27.     glMatrixMode( GL_PROJECTION );
  28.     glLoadIdentity();
  29.  
  30.     glOrtho( 0, 800, yMin, yMax, -5.0, 1.0 );
  31.     glMatrixMode( GL_MODELVIEW );
  32.  
  33. }
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