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    <p>I have excellent experience with TurboVNC/VirtualGL. In
      particular, Chimera works very well and the performance on a
      reasonably rapid network is like sitting in front of the
      workstation! I usually connect to my Windows PC remotely from home
      or any place in the world and from there to two Linux
      workstations. If the network is slow you can reduce the number of
      colors to get a better performance! <br>
    </p>
    <p>bw Dieter<br>
    </p>
    <pre class="moz-signature" cols="72">------------------------------------------------------------------------
Dieter Blaas,
Max F. Perutz Laboratories
Medical University of Vienna, 
Inst. Med. Biochem., Vienna Biocenter (VBC), 
Dr. Bohr Gasse 9/3, 
A-1030 Vienna, Austria, 
Tel: 0043 1 4277 61630, 
Fax: 0043 1 4277 9616, 
e-mail: <a class="moz-txt-link-abbreviated" href="mailto:dieter.blaas@meduniwien.ac.at">dieter.blaas@meduniwien.ac.at</a>
------------------------------------------------------------------------</pre>
    <div class="moz-cite-prefix">Am 03.02.2019 um 21:38 schrieb Reza
      Khayat:<br>
    </div>
    <blockquote type="cite" cite="mid:1549226291352.27392@ccny.cuny.edu">
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      <p>​Very cool, thanks Steve.  Which do you use? <br>
      </p>
      <p><br>
      </p>
      <div id="Signature">
        <div name="divtagdefaultwrapper"
          style="font-family:Calibri,Arial,Helvetica,sans-serif;
          font-size:; margin:0">
          Reza Khayat, PhD
          <div>Assistant Professor </div>
          <div>City College of New York</div>
          <div>Department of Chemistry</div>
          <div>New York, NY 10031</div>
        </div>
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        <div id="divRplyFwdMsg" dir="ltr"><font style="font-size:11pt"
            face="Calibri, sans-serif" color="#000000"><b>From:</b> 3dem
            <a class="moz-txt-link-rfc2396E" href="mailto:3dem-bounces@ncmir.ucsd.edu"><3dem-bounces@ncmir.ucsd.edu></a> on behalf of Ludtke,
            Steven J <a class="moz-txt-link-rfc2396E" href="mailto:sludtke@bcm.edu"><sludtke@bcm.edu></a><br>
            <b>Sent:</b> Sunday, February 3, 2019 2:38 PM<br>
            <b>To:</b> <a class="moz-txt-link-abbreviated" href="mailto:frankg@bgu.ac.il">frankg@bgu.ac.il</a><br>
            <b>Cc:</b> <a class="moz-txt-link-abbreviated" href="mailto:3dem@ncmir.ucsd.edu">3dem@ncmir.ucsd.edu</a><br>
            <b>Subject:</b> [EXTERNAL] Re: [3dem] visualization of data
            from a remote server</font>
          <div> </div>
        </div>
        <div>
          <div class="">Maybe a quick summary of some of the issues for
            CryoEM:</div>
          <div class=""><br class="">
          </div>
          <div class="">1) remote X sessions</div>
          <div class="">pros: </div>
          <div class=""> - simple for any machine with an X-client</div>
          <div class="">cons:</div>
          <div class=""> - very bandwidth intensive, poor interactivity
            on slow links</div>
          <div class=""> - often requires tricky configuration work to
            make OpenGL function at all</div>
          <div class=""> - openGL badly broken on many clients, and
            slightly broken on most, not always immediately obvious</div>
          <div class=""><br class="">
          </div>
          <div class="">2) compressed remote X sessions (NX, X2GO, etc.)</div>
          <div class="">pros:</div>
          <div class=""> - compression gives much improved performance</div>
          <div class=""> - may support OpenGL</div>
          <div class="">cons:</div>
          <div class=""> - historically this has gone through many
            cycles of working/not working with OpenGL</div>
          <div class=""> - compression based on X protocol. Great for
            things like word-processors, but not great for
            graphics/image intensive work</div>
          <div class=""><br class="">
          </div>
          <div class="">3) TurboVNC/VirtualGL</div>
          <div class="">pros:</div>
          <div class=""> - developed by NSF supercomputing centers
            specifically for remote 3-D display</div>
          <div class=""> - sends compressed image data tiles, so all
            rendering done on the server</div>
          <div class=""> - works perfectly almost 100% of the time once
            configured</div>
          <div class=""> - cross-platform client</div>
          <div class=""> - server set up on many clusters</div>
          <div class=""> - can be tunneled through SSH easily</div>
          <div class="">cons:</div>
          <div class=""> - rendering done server-side, so more CPU/GPU
            load on the server (in practice I've never seen a problem)</div>
          <div class=""> - needs to be setup on server and client. Root
            privileges required on server</div>
          <div class=""> - X2GO may be more efficient for programs which
            aren't graphics intensive</div>
          <div class=""><br class="">
          </div>
          <div class="">4) Screen-sharing solutions (TeamViewer and
            others)</div>
          <div class="">pros:</div>
          <div class=""> - easy, just works</div>
          <div class="">cons:</div>
          <div class=""> - usually costs $</div>
          <div class=""> - data routed through 3rd party service </div>
          <div class=""> - network administrators do NOT like this, as
            it bypasses established network security and can expose the
            entire institutional network</div>
          <div class=""> - like TurboVNC, involves compression, but may
            not be under user control (bandwidth sensitive)</div>
          <div class=""><br class="">
            <div class="">
              <div dir="auto" class="" style="color:rgb(0,0,0);
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                <div dir="auto" class="" style="color:rgb(0,0,0);
                  letter-spacing:normal; text-align:start;
                  text-indent:0px; text-transform:none;
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                  word-wrap:break-word; line-break:after-white-space">
                  <div dir="auto" class="" style="word-wrap:break-word;
                    line-break:after-white-space">
                    <div style="color:rgb(0,0,0); letter-spacing:normal;
                      text-align:start; text-indent:0px;
                      text-transform:none; white-space:normal;
                      word-spacing:0px">
                      <font class="" face="Courier"><span class=""
                          style="font-size:14px">--------------------------------------------------------------------------------------<br
                            class="">
                          Steven Ludtke, Ph.D. <<a
                            href="mailto:sludtke@bcm.edu" class=""
                            moz-do-not-send="true">sludtke@bcm.edu</a>> 
                                              Baylor College
                          of Medicine <br class="">
                          Charles C. Bell Jr., Professor of
                          Structural Biology<br class="">
                          Dept. of Biochemistry and Molecular Biology   
                                            (<a
href="https://urldefense.proofpoint.com/v2/url?u=http-3A__www.bcm.edu_biochem&d=DwMGaQ&c=4NmamNZG3KTnUCoC6InoLJ6KV1tbVKrkZXHRwtIMGmo&r=1DzJFW0v6TgEhkW1gy_-ke-RbtvS1fzEbD5_hcb9Up0&m=pGKZRJHtbSTUBufrz74ICbWnAKdmU3oypG4IrnnFSSY&s=OamfHEl523bV4-MxWqYepMxI-LFxkK2ffmDdZSTfp1k&e="
                            class="" moz-do-not-send="true">www.bcm.edu/biochem</a>)<br
                            class="">
                          Academic Director, CryoEM Core               
                                                  (<a
href="https://urldefense.proofpoint.com/v2/url?u=http-3A__cryoem.bcm.edu&d=DwMGaQ&c=4NmamNZG3KTnUCoC6InoLJ6KV1tbVKrkZXHRwtIMGmo&r=1DzJFW0v6TgEhkW1gy_-ke-RbtvS1fzEbD5_hcb9Up0&m=pGKZRJHtbSTUBufrz74ICbWnAKdmU3oypG4IrnnFSSY&s=a_7gG6Rjk6Qv82OywEwFwpDKktvdo5PzvAUkIcAsLAs&e="
                            class="" moz-do-not-send="true">cryoem.bcm.edu</a>)<br
                            class="">
                          Co-Director CIBR Center                       
                                      (<a
href="https://urldefense.proofpoint.com/v2/url?u=http-3A__www.bcm.edu_research_cibr&d=DwMGaQ&c=4NmamNZG3KTnUCoC6InoLJ6KV1tbVKrkZXHRwtIMGmo&r=1DzJFW0v6TgEhkW1gy_-ke-RbtvS1fzEbD5_hcb9Up0&m=pGKZRJHtbSTUBufrz74ICbWnAKdmU3oypG4IrnnFSSY&s=7h6DxN3uqbos-PDyaZsMEIf99X3AOkM73WvN1dHaNyQ&e="
                            class="" moz-do-not-send="true">www.bcm.edu/research/cibr</a>)<br
                            class="">
                          <br class="">
                        </span></font><br class="">
                    </div>
                  </div>
                </div>
              </div>
            </div>
            <div><br class="">
              <blockquote type="cite" class="">
                <div class="">On Feb 3, 2019, at 1:08 PM, <a
                    href="mailto:frankg@bgu.ac.il" class=""
                    moz-do-not-send="true">
                    frankg@bgu.ac.il</a> wrote:</div>
                <br class="Apple-interchange-newline">
                <div class=""><font class=""
                    style="font-family:Helvetica; font-style:normal;
                    font-weight:normal; letter-spacing:normal;
                    text-align:start; text-indent:0px;
                    text-transform:none; white-space:normal;
                    word-spacing:0px; text-decoration:none" size="2"><b
                      class="">***CAUTION:*** This email is not from a
                      BCM Source. Only click links or open attachments
                      you know are safe.</b></font><span class=""
                    style="font-family:Helvetica; font-size:18px;
                    font-style:normal; font-weight:normal;
                    letter-spacing:normal; text-align:start;
                    text-indent:0px; text-transform:none;
                    white-space:normal; word-spacing:0px;
                    text-decoration:none; float:none;
                    display:inline!important"></span>
                  <hr class="" style="font-family:Helvetica;
                    font-size:18px; font-style:normal;
                    font-weight:normal; letter-spacing:normal;
                    text-align:start; text-indent:0px;
                    text-transform:none; white-space:normal;
                    word-spacing:0px; text-decoration:none">
                  <div class="WordSection1"
                    style="font-family:Helvetica; font-size:18px;
                    font-style:normal; font-weight:normal;
                    letter-spacing:normal; text-align:start;
                    text-indent:0px; text-transform:none;
                    white-space:normal; word-spacing:0px;
                    text-decoration:none">
                    <div class="" style="margin:0cm 0cm 0.0001pt;
                      font-size:12pt; font-family:"Times New
                      Roman",serif">
                      <span class="" style="font-size:11pt;
                        font-family:Calibri,sans-serif;
                        color:rgb(31,73,125)">Hi,</span></div>
                    <div class="" style="margin:0cm 0cm 0.0001pt;
                      font-size:12pt; font-family:"Times New
                      Roman",serif">
                      <span class="" style="font-size:11pt;
                        font-family:Calibri,sans-serif;
                        color:rgb(31,73,125)"> </span></div>
                    <div class="" style="margin:0cm 0cm 0.0001pt;
                      font-size:12pt; font-family:"Times New
                      Roman",serif">
                      <span class="" style="font-size:11pt;
                        font-family:Calibri,sans-serif;
                        color:rgb(31,73,125)">We recently installed X2Go
                        on our servers using the lightweight XFCE
                        graphical environment.</span></div>
                    <div class="" style="margin:0cm 0cm 0.0001pt;
                      font-size:12pt; font-family:"Times New
                      Roman",serif">
                      <span class="" style="font-size:11pt;
                        font-family:Calibri,sans-serif;
                        color:rgb(31,73,125)">This works very well for
                        us.</span></div>
                    <div class="" style="margin:0cm 0cm 0.0001pt;
                      font-size:12pt; font-family:"Times New
                      Roman",serif">
                      <span class="" style="font-size:11pt;
                        font-family:Calibri,sans-serif;
                        color:rgb(31,73,125)">There are versions of X2Go
                        clients for Linux, W10 and Mac.</span></div>
                    <div class="" style="margin:0cm 0cm 0.0001pt;
                      font-size:12pt; font-family:"Times New
                      Roman",serif">
                      <span class="" style="font-size:11pt;
                        font-family:Calibri,sans-serif;
                        color:rgb(31,73,125)"> </span></div>
                    <div class="" style="margin:0cm 0cm 0.0001pt;
                      font-size:12pt; font-family:"Times New
                      Roman",serif">
                      <span class="" style="font-size:11pt;
                        font-family:Calibri,sans-serif;
                        color:rgb(31,73,125)">Gabriel A. Frank,</span></div>
                    <div class="" style="margin:0cm 0cm 0.0001pt;
                      font-size:12pt; font-family:"Times New
                      Roman",serif">
                      <span class="" style="font-size:11pt;
                        font-family:Calibri,sans-serif;
                        color:rgb(31,73,125)">BGU</span></div>
                    <div class="" style="margin:0cm 0cm 0.0001pt;
                      font-size:12pt; font-family:"Times New
                      Roman",serif">
                      <span class="" style="font-size:11pt;
                        font-family:Calibri,sans-serif;
                        color:rgb(31,73,125)"> </span></div>
                    <div class="">
                      <div class="" style="border-style:solid none none;
                        border-top-width:1pt;
                        border-top-color:rgb(225,225,225); padding:3pt
                        0cm 0cm">
                        <div class="" style="margin:0cm 0cm 0.0001pt;
                          font-size:12pt; font-family:"Times New
                          Roman",serif">
                          <b class=""><span class=""
                              style="font-size:11pt;
                              font-family:Calibri,sans-serif">From:</span></b><span
                            class="" style="font-size:11pt;
                            font-family:Calibri,sans-serif"><span
                              class="Apple-converted-space"> </span>3dem
                            [<a
                              href="mailto:3dem-bounces@ncmir.ucsd.edu"
                              class="" style="color:rgb(149,79,114);
                              text-decoration:underline"
                              moz-do-not-send="true">mailto:3dem-bounces@ncmir.ucsd.edu</a>]<span
                              class="Apple-converted-space"> </span><b
                              class="">On Behalf Of<span
                                class="Apple-converted-space"> </span></b>Amar
                            Dhananjai Parvate<br class="">
                            <b class="">Sent:</b><span
                              class="Apple-converted-space"> </span><span
                              dir="RTL" class="" lang="HE">יום א 03
                              פברואר 2019 20:35</span><br class="">
                            <b class="">To:</b><span
                              class="Apple-converted-space"> </span>Michael
                            Elbaum <<a
                              href="mailto:michael.elbaum@weizmann.ac.il"
                              class="" style="color:rgb(149,79,114);
                              text-decoration:underline"
                              moz-do-not-send="true">michael.elbaum@weizmann.ac.il</a>>;<span
                              class="Apple-converted-space"> </span><a
                              href="mailto:3dem@ncmir.ucsd.edu" class=""
                              style="color:rgb(149,79,114);
                              text-decoration:underline"
                              moz-do-not-send="true">3dem@ncmir.ucsd.edu</a><br
                              class="">
                            <b class="">Subject:</b><span
                              class="Apple-converted-space"> </span>Re:
                            [3dem] visualization of data from a remote
                            server</span></div>
                      </div>
                    </div>
                    <div class="" style="margin:0cm 0cm 0.0001pt;
                      font-size:12pt; font-family:"Times New
                      Roman",serif">
                       </div>
                    <div class="">
                      <div class="" style="margin:0cm 0cm 0.0001pt;
                        font-size:12pt; font-family:"Times New
                        Roman",serif">
                        <span class=""
                          style="font-family:Calibri,sans-serif">Dear
                          All</span></div>
                    </div>
                    <div class="">
                      <div class="" style="margin:0cm 0cm 0.0001pt;
                        font-size:12pt; font-family:"Times New
                        Roman",serif">
                        <span class=""
                          style="font-family:Calibri,sans-serif">I am
                          very glad to know i am not the only one with
                          remote log in GUI visualization problems and
                          ... even better that ppl on this forum have
                          some solutions. </span></div>
                    </div>
                    <div class="">
                      <div class="" style="margin:0cm 0cm 0.0001pt;
                        font-size:12pt; font-family:"Times New
                        Roman",serif">
                        <span class=""
                          style="font-family:Calibri,sans-serif">Here is
                          what i am trying to do and of course its not
                          working... </span></div>
                    </div>
                    <div class="">
                      <div class="" style="margin:0cm 0cm 0.0001pt;
                        font-size:12pt; font-family:"Times New
                        Roman",serif">
                        <span class=""
                          style="font-family:Calibri,sans-serif">1) My
                          workstation is a linux machine with Centos 7.
                          I can access both single particle and
                          tomography software through my home
                          directory. </span></div>
                    </div>
                    <div class="">
                      <div class="" style="margin:0cm 0cm 0.0001pt;
                        font-size:12pt; font-family:"Times New
                        Roman",serif">
                        <span class=""
                          style="font-family:Calibri,sans-serif">2) I
                          have a Windows 10 laptop where i have
                          installed my institute recommended Putty and
                          Xming client for remote login</span></div>
                    </div>
                    <div class="">
                      <div class="" style="margin:0cm 0cm 0.0001pt;
                        font-size:12pt; font-family:"Times New
                        Roman",serif">
                        <span class=""
                          style="font-family:Calibri,sans-serif">3)
                          While off campus, my VPN works fine, i can log
                          in to my workstation, access home directory
                          and run anything command line properly. </span></div>
                    </div>
                    <div class="">
                      <div class="" style="margin:0cm 0cm 0.0001pt;
                        font-size:12pt; font-family:"Times New
                        Roman",serif">
                        <b class=""><span class=""
                            style="font-family:Calibri,sans-serif">4)
                            Issue comes when anything GUI needs to be
                            displayed.<span
                              class="Apple-converted-space"> </span></span></b><span
                          class=""
                          style="font-family:Calibri,sans-serif">I have
                          followed several tutorials for Putty and
                          Xming, tried loging in to the computer via IP
                          or<span class="Apple-converted-space"> </span><a
                            href="mailto:user@home.edu" class=""
                            style="color:rgb(149,79,114);
                            text-decoration:underline"
                            moz-do-not-send="true">user@home.edu</a>.
                          Have tried several local hosts for X11
                          forwarding... and it doesnt seem to work. </span></div>
                    </div>
                    <div class="">
                      <div class="" style="margin:0cm 0cm 0.0001pt;
                        font-size:12pt; font-family:"Times New
                        Roman",serif">
                        <span class=""
                          style="font-family:Calibri,sans-serif">I have
                          even tried to edit the ssh-config file. where
                          the X11 forwarding is turned off by default.  </span></div>
                    </div>
                    <div class="">
                      <div class="" style="margin:0cm 0cm 0.0001pt;
                        font-size:12pt; font-family:"Times New
                        Roman",serif">
                        <span class=""
                          style="font-family:Calibri,sans-serif">Basically
                          if i try to open a .mrc file via say 3dmod, i
                          see the file being read in the main window but
                          the connection is refused while displaying the
                          zap window. </span></div>
                    </div>
                    <div class="">
                      <div class="" style="margin:0cm 0cm 0.0001pt;
                        font-size:12pt; font-family:"Times New
                        Roman",serif">
                        <span class=""
                          style="font-family:Calibri,sans-serif"> </span></div>
                    </div>
                    <div class="">
                      <div class="" style="margin:0cm 0cm 0.0001pt;
                        font-size:12pt; font-family:"Times New
                        Roman",serif">
                        <span class=""
                          style="font-family:Calibri,sans-serif">Be glad
                          if anyone can share any solutions on this
                          regard...</span></div>
                    </div>
                    <div class="">
                      <div class="" style="margin:0cm 0cm 0.0001pt;
                        font-size:12pt; font-family:"Times New
                        Roman",serif">
                        <span class=""
                          style="font-family:Calibri,sans-serif"> </span></div>
                    </div>
                    <div class="">
                      <div class="" style="margin:0cm 0cm 0.0001pt;
                        font-size:12pt; font-family:"Times New
                        Roman",serif">
                        <span class=""
                          style="font-family:Calibri,sans-serif">P.S. -
                          The Putty+X forwarding worked for my colleague
                          who basically has the same laptop as mine, and
                          we are in the same lab, trying to access the
                          same set of imod GUIs.  🤔</span></div>
                    </div>
                    <div class="">
                      <div class="" style="margin:0cm 0cm 0.0001pt;
                        font-size:12pt; font-family:"Times New
                        Roman",serif">
                        <span class=""
                          style="font-family:Calibri,sans-serif"> </span></div>
                    </div>
                    <div id="signature" class="">
                      <div id="divtagdefaultwrapper" class="">
                        <div class="" style="margin:0cm 0cm 0.0001pt;
                          font-size:12pt; font-family:"Times New
                          Roman",serif; background-color:white">
                          <span class=""
                            style="font-family:Calibri,sans-serif">Amar
                            Parvate</span></div>
                        <div class="" style="margin:0cm 0cm 0.0001pt;
                          font-size:12pt; font-family:"Times New
                          Roman",serif; background-color:white">
                          <span class=""
                            style="font-family:Calibri,sans-serif">Purdue
                            University</span></div>
                        <div class="" style="margin:0cm 0cm 0.0001pt;
                          font-size:12pt; font-family:"Times New
                          Roman",serif; background-color:white">
                          <span class=""
                            style="font-family:Calibri,sans-serif">Department
                            of Biological Sciences</span></div>
                        <div class="" style="margin:0cm 0cm 0.0001pt;
                          font-size:12pt; font-family:"Times New
                          Roman",serif; background-color:white">
                          <span class=""
                            style="font-family:Calibri,sans-serif"> </span></div>
                      </div>
                    </div>
                    <div class="MsoNormal" style="margin:0cm 0cm
                      0.0001pt; font-size:12pt; font-family:"Times
                      New Roman",serif; text-align:center"
                      align="center">
                      <hr class="" width="98%" size="3" align="center">
                    </div>
                    <div id="divRplyFwdMsg" class="">
                      <div class="" style="margin:0cm 0cm 0.0001pt;
                        font-size:12pt; font-family:"Times New
                        Roman",serif">
                        <b class=""><span class=""
                            style="font-size:11pt;
                            font-family:Calibri,sans-serif">From:</span></b><span
                          class="" style="font-size:11pt;
                          font-family:Calibri,sans-serif"><span
                            class="Apple-converted-space"> </span>3dem
                          <<a
                            href="mailto:3dem-bounces@ncmir.ucsd.edu"
                            class="" style="color:rgb(149,79,114);
                            text-decoration:underline"
                            moz-do-not-send="true">3dem-bounces@ncmir.ucsd.edu</a>>
                          on behalf of Michael Elbaum <<a
                            href="mailto:michael.elbaum@weizmann.ac.il"
                            class="" style="color:rgb(149,79,114);
                            text-decoration:underline"
                            moz-do-not-send="true">michael.elbaum@weizmann.ac.il</a>><br
                            class="">
                          <b class="">Sent:</b><span
                            class="Apple-converted-space"> </span>Sunday,
                          February 3, 2019 10:27 AM<br class="">
                          <b class="">To:</b><span
                            class="Apple-converted-space"> </span><a
                            href="mailto:3dem@ncmir.ucsd.edu" class=""
                            style="color:rgb(149,79,114);
                            text-decoration:underline"
                            moz-do-not-send="true">3dem@ncmir.ucsd.edu</a><br
                            class="">
                          <b class="">Subject:</b><span
                            class="Apple-converted-space"> </span>[3dem]
                          visualization of data from a remote server</span></div>
                      <div class="">
                        <div class="" style="margin:0cm 0cm 0.0001pt;
                          font-size:12pt; font-family:"Times New
                          Roman",serif">
                           </div>
                      </div>
                    </div>
                    <div class="">
                      <div class="">
                        <div class="">
                          <div class="" style="margin:0cm 0cm 0.0001pt;
                            font-size:12pt; font-family:"Times New
                            Roman",serif">
                            <span class="" style="font-size:10pt;
                              font-family:Tahoma,sans-serif"><br
                                class="">
                              Hi all,<br class="">
                              <br class="">
                              I'm normally using a powerful server for
                              image processing, and then I look at the
                              data by remote ssh with X forwarding.
                              Recently I upgraded the linux OS on my
                              laptop (to Ubuntu 18.04) and all sorts of
                              programs stopped working this way,
                              including 3dmod. It turned out to be a
                              much broader problem having to do with
                              OpenGL. Indirect rendering, which is what
                              we need, is turned off by default in newer
                              versions of X. I assume others have
                              encountered such trouble as well. Since it
                              took quite some digging to find a solution
                              I'm posting it here.<br class="">
                              <br class="">
                              For those who boot into a command line
                              interface with a black screen and start an
                              X session manually, (e.g., startx -- :2)
                              the fix is simple.<span
                                class="Apple-converted-space"> </span><br
                                class="">
                              Edit the file /usr/bin/startx and change
                              the line defaultclientargs="" to
                              defaultclientargs="+iglx"<br class="">
                              +iglx allows indirect rendering by OpenGL
                              applications.<br class="">
                              This is not relevant to most of us.<br
                                class="">
                              <br class="">
                              For those who boot the computer and expect
                              to see the graphical display right away
                              it's a bit trickier. Ubuntu uses X or
                              Wayland for the graphical interface,
                              depending on the version. The solution I
                              found is only for X, so we have to revert
                              to that first. It's done in two steps, as
                              root:<br class="">
                              1) In the file /etc/gdm3/custom.conf,
                              uncomment (erase the hash) the line
                              #WaylandEnable=false. (In Ubuntu it should
                              be enough to start GNOME in Xorg, which is
                              one of the login options.)<br class="">
                              2) Create a new file
                              /usr/share/X11/xorg.conf.d/50-iglx.conf:<br
                                class="">
                              Section "ServerFlags" <span
                                class="Apple-converted-space"> </span><br
                                class="">
                              Option "AllowIndirectGLX" "on" <span
                                class="Apple-converted-space"> </span><br
                                class="">
                                  Option "IndirectGLX" "on" <span
                                class="Apple-converted-space"> </span><br
                                class="">
                              EndSection<span
                                class="Apple-converted-space"> </span><br
                                class="">
                              Reboot and it should work. at your own
                              risk, of course...<br class="">
                              Other distributions might put these files
                              in different places.<br class="">
                              <br class="">
                              Here are some useful resources:<br
                                class="">
                              <a
href="https://urldefense.proofpoint.com/v2/url?u=https-3A__www.visitusers.org_index.php-3Ftitle-3DRe-2Denabling-5FINdirect-5Fglx-5Fon-5Fyour-5FX-5Fserver&d=DwMGaQ&c=ZQs-KZ8oxEw0p81sqgiaRA&r=Dk5VoQQ-wINYVssLMZihyC5Dj_sWYKxCyKz9E4Lp3gc&m=qY9gTMBGM37MS6-wNHhwW5WhlSPN9gt1MjWTiO0Y22Y&s=LK4vpKWDMPgF6hj-Tw_TcRRUYUK8yQNvD7g3hS-Wa3o&e="
                                class="" style="color:rgb(149,79,114);
                                text-decoration:underline"
                                moz-do-not-send="true">https://www.visitusers.org/index.php?title=Re-enabling_INdirect_glx_on_your_X_server</a><br
                                class="">
                              <a
href="https://urldefense.proofpoint.com/v2/url?u=https-3A__lists.freedesktop.org_archives_xorg_2016-2DMay_058072.html&d=DwMGaQ&c=ZQs-KZ8oxEw0p81sqgiaRA&r=Dk5VoQQ-wINYVssLMZihyC5Dj_sWYKxCyKz9E4Lp3gc&m=qY9gTMBGM37MS6-wNHhwW5WhlSPN9gt1MjWTiO0Y22Y&s=qtB13C4ftJryMYlU48WVrGF-Q8ikzbV_TJCEbD-9zWU&e="
                                class="" style="color:rgb(149,79,114);
                                text-decoration:underline"
                                moz-do-not-send="true">https://lists.freedesktop.org/archives/xorg/2016-May/058072.html</a><br
                                class="">
                              <a
href="https://urldefense.proofpoint.com/v2/url?u=https-3A__askubuntu.com_questions_745135_how-2Dto-2Denable-2Dindirect-2Dglx-2Dcontexts-2Diglx-2Din-2Dubuntu-2D14-2D04-2Dlts-2Dwith-2Dnvidia-2Dgfx_747088&d=DwMGaQ&c=ZQs-KZ8oxEw0p81sqgiaRA&r=Dk5VoQQ-wINYVssLMZihyC5Dj_sWYKxCyKz9E4Lp3gc&m=qY9gTMBGM37MS6-wNHhwW5WhlSPN9gt1MjWTiO0Y22Y&s=dmm1y_NIZbPi1OHVN5WGTrkH8LDK0IFknU-3FYc3Tak&e="
                                class="" style="color:rgb(149,79,114);
                                text-decoration:underline"
                                moz-do-not-send="true">https://askubuntu.com/questions/745135/how-to-enable-indirect-glx-contexts-iglx-in-ubuntu-14-04-lts-with-nvidia-gfx/747088</a><br
                                class="">
                              <br class="">
                              There seems to be a similar issue with
                              XQuartz on the Mac, which is addressed by
                              reverting to the last version that worked.<br
                                class="">
                              <br class="">
                              There was another instruction to add in
                              the file
                              /usr/share/lightdm/lightdm.conf.d/50-xserver-command.conf<br
                                class="">
                              [SeatDefaults]<br class="">
                              # Dump core<br class="">
                              xserver-command=X -core +iglx<br class="">
                              but this didn't work for me.<br class="">
                              <br class="">
                              As for Wayland, typing Xwayland -h shows
                              that the options include +iglx, but I
                              wasn't able to find a config file for
                              passing it startup options.<br class="">
                              <br class="">
                              A longer term solution seems to be
                              VirtualGL or TurboVNC. Does anyone have
                              those working with 3dem visualization
                              software?<br class="">
                              <br class="">
                              regards,<br class="">
                              Michael</span></div>
                        </div>
                      </div>
                    </div>
                  </div>
                  <span class="" style="font-family:Helvetica;
                    font-size:18px; font-style:normal;
                    font-weight:normal; letter-spacing:normal;
                    text-align:start; text-indent:0px;
                    text-transform:none; white-space:normal;
                    word-spacing:0px; text-decoration:none; float:none;
                    display:inline!important">_______________________________________________</span><br
                    class="" style="font-family:Helvetica;
                    font-size:18px; font-style:normal;
                    font-weight:normal; letter-spacing:normal;
                    text-align:start; text-indent:0px;
                    text-transform:none; white-space:normal;
                    word-spacing:0px; text-decoration:none">
                  <span class="" style="font-family:Helvetica;
                    font-size:18px; font-style:normal;
                    font-weight:normal; letter-spacing:normal;
                    text-align:start; text-indent:0px;
                    text-transform:none; white-space:normal;
                    word-spacing:0px; text-decoration:none; float:none;
                    display:inline!important">3dem mailing list</span><br
                    class="" style="font-family:Helvetica;
                    font-size:18px; font-style:normal;
                    font-weight:normal; letter-spacing:normal;
                    text-align:start; text-indent:0px;
                    text-transform:none; white-space:normal;
                    word-spacing:0px; text-decoration:none">
                  <a href="mailto:3dem@ncmir.ucsd.edu" class=""
                    style="color:rgb(149,79,114);
                    text-decoration:underline; font-family:Helvetica;
                    font-size:18px; font-style:normal;
                    font-weight:normal; letter-spacing:normal;
                    orphans:auto; text-align:start; text-indent:0px;
                    text-transform:none; white-space:normal;
                    widows:auto; word-spacing:0px"
                    moz-do-not-send="true">3dem@ncmir.ucsd.edu</a><br
                    class="" style="font-family:Helvetica;
                    font-size:18px; font-style:normal;
                    font-weight:normal; letter-spacing:normal;
                    text-align:start; text-indent:0px;
                    text-transform:none; white-space:normal;
                    word-spacing:0px; text-decoration:none">
                  <a
href="https://urldefense.proofpoint.com/v2/url?u=https-3A__mail.ncmir.ucsd.edu_mailman_listinfo_3dem&d=DwICAg&c=ZQs-KZ8oxEw0p81sqgiaRA&r=Dk5VoQQ-wINYVssLMZihyC5Dj_sWYKxCyKz9E4Lp3gc&m=qY9gTMBGM37MS6-wNHhwW5WhlSPN9gt1MjWTiO0Y22Y&s=OOiMvjHx9Um0uPBBumyd_FM2TbKgtQbFuoxED5ii8to&e="
                    class="" style="color:rgb(149,79,114);
                    text-decoration:underline; font-family:Helvetica;
                    font-size:18px; font-style:normal;
                    font-weight:normal; letter-spacing:normal;
                    orphans:auto; text-align:start; text-indent:0px;
                    text-transform:none; white-space:normal;
                    widows:auto; word-spacing:0px"
                    moz-do-not-send="true">https://urldefense.proofpoint.com/v2/url?u=https-3A__mail.ncmir.ucsd.edu_mailman_listinfo_3dem&d=DwICAg&c=ZQs-KZ8oxEw0p81sqgiaRA&r=Dk5VoQQ-wINYVssLMZihyC5Dj_sWYKxCyKz9E4Lp3gc&m=qY9gTMBGM37MS6-wNHhwW5WhlSPN9gt1MjWTiO0Y22Y&s=OOiMvjHx9Um0uPBBumyd_FM2TbKgtQbFuoxED5ii8to&e=</a></div>
              </blockquote>
            </div>
            <br class="">
          </div>
        </div>
      </div>
      <br>
      <fieldset class="mimeAttachmentHeader"></fieldset>
      <pre class="moz-quote-pre" wrap="">_______________________________________________
3dem mailing list
<a class="moz-txt-link-abbreviated" href="mailto:3dem@ncmir.ucsd.edu">3dem@ncmir.ucsd.edu</a>
<a class="moz-txt-link-freetext" href="https://mail.ncmir.ucsd.edu/mailman/listinfo/3dem">https://mail.ncmir.ucsd.edu/mailman/listinfo/3dem</a>
</pre>
    </blockquote>
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