On 22 May 2012 14:42, Anuj Phogat <span dir="ltr"><<a href="mailto:anuj.phogat@gmail.com" target="_blank">anuj.phogat@gmail.com</a>></span> wrote:<br><div class="gmail_quote"><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"> <div class="HOEnZb"><div class="h5">On Tue, May 22, 2012 at 8:37 AM, Paul Berry <<a href="mailto:stereotype441@gmail.com">stereotype441@gmail.com</a>> wrote:<br> > On 18 May 2012 16:56, Anuj Phogat <<a href="mailto:anuj.phogat@gmail.com">anuj.phogat@gmail.com</a>> wrote:<br> >> +<br> >> + /* Draw test pattern in mulisample test_fbo with GL_LINE_SMOOTH<br> >> + * enabled<br> >> + */<br> >> + glEnable(GL_LINE_SMOOTH);<br> >> + glHint(GL_LINE_SMOOTH_HINT, GL_NICEST);<br> >> + glDisable (GL_DEPTH_TEST);<br> ><br> ><br> > Can you comment on why it's necessary to disable depth testing here? It's<br> > not immediately obvious to me.<br> ><br> </div></div><div></div>It's required to correctly render overlapping smooth primitives.<br> Otherwise we have to render the primitives<br> in back to front order.<br> For more explanation read OpenGL FAQ 14.150:<br> <a href="http://www.opengl.org/archives/resources/faq/technical/rasterization.htm" target="_blank">http://www.opengl.org/archives/resources/faq/technical/rasterization.htm</a><br> <div class="HOEnZb"><div class="h5"><br></div></div></blockquote><div><br>Ok, thanks. I'm not 100% sure this is necessary for this test (since it's not drawing any overlapping lines) but I'm ok with leaving it in anyhow to be on the safe side. Would you mind including a comment at this point in the file to clarify?<br> <br>With that change, this patch is:<br>Reviewed-by: Paul Berry <<a href="mailto:stereotype441@gmail.com">stereotype441@gmail.com</a>><br></div></div>