[AD] Primitives not drawing without glFlush on Intel (Windows 7)

[Trent Gamblin <nooskewl@xxxxxxxxxx>]

When  I'm drawing primitives on this new netbook with Intel graphics (I
think it's when drawing 2+ high level primitives in a row, like rectangles
and triangles), the later drawn primitives sometimes do not show up unless I
call glFlush after drawing all of the primitives. Is there anything that can
be done about it? An example:

al_draw_filled_rectangle(startx, y+1, endx, y+3+(thick ? 1 : 0),
al_color_name("black"));
al_draw_filled_rectangle(startx, y+1, startx+length, y+2, darker);
al_draw_filled_rectangle(startx, y+2, startx+length, y+3+(thick ? 1 : 0),
color);
// Don't know why but my netbook needs this
if (al_get_display_flags(engine->get_display()) & ALLEGRO_OPENGL) {
   glFlush();
}

al_draw_tinted_bitmap(left, gauge_hilight_color, x, y, 0);

Trent