I found out what is going on,
PDL does double-buffer, at the line:
# PDL/Graphics/TriD/GL.pm" line 789
sub display {
# ...
$this->{_GLObject}->glXSwapBuffers();
}
display is called from
twiddle
which does the model
fly-through stuff. My flicker came from using
hold3d,
points3d then
imag3d_ns
but points3d calls graph_object (calling
twiddle_current then twiddle), so the points were
drawn, the buffers swapped making imag3d_ns seem to
flicker. I just need to avoid the points3d shortcut,
and other forms using graph_object.
Brad