gazebo7: hangs on downloading models
I know this question has been asked before (#q6870, #q6347, #q18009 and others), but seeing as there is a web server involved, those older questions (and their answers) might not be applicable any more, so here is a new one.
While starting a fresh install of Gazebo 7 (with ROS Kinetic, but I'm not sure that is relevant here) with gzserver --verbose the only output produced is:
Gazebo multi-robot simulator, version 7.0.0
Copyright (C) 2012-2016 Open Source Robotics Foundation.
Released under the Apache 2 License.
http://gazebosim.org
[Msg] Waiting for master.
[Msg] Connected to gazebo master @ http://127.0.0.1:11345
[Msg] Publicized address: 131.180.31.243
[Err] [RenderEngine.cc:699] Can't open display:
[Wrn] [RenderEngine.cc:97] Unable to create X window. Rendering will be disabled
[Wrn] [RenderEngine.cc:301] Cannot initialize render engine since render path type is NONE. Ignore this warning ifrendering has been turned off on purpose.
[Wrn] [ModelDatabase.cc:339] Getting models from[http://gazebosim.org/models/]. This may take a few seconds.
And then nothing happens (there being no X window is indeed "on purpose").
I've left this running for 30 minutes but there was no progress so I ctrl+c it.
Starting gazebo --verbose results in an unresponse GUI with a black window and the same (similar) output on the console.
This is on a clean internet connection: no proxies, no caching proxies, no NAT, nothing.
Checking gazebosim.org/models/ myself I get the following page:
this could just be a default "indexing is not configured" error, or caused by me asking for index.html which doesn't exist of course. I noticed that models.gazebosim.org does work (but as I'm not an expert Gazebo user I don't know whether the two point to the same resources).
I guess the question is: is there some way to ascertain the status of gazebosim.org/models so we can gauge whether it makes sense to keep waiting for gzserver to complete the downloads?
Would creating something like https://status.ros.org (or adding the relevant Gazebo hosts to that) be an option? Does that already exist and am I just not aware, or does it not make sense and is my problem caused by something else?
Are you running just the `gzserver --verbose` command without any world?
Yes. Just the bare `gzserver`, no world file specified.
When I run this command, the terminal output ends with the `Publicized address:` line. And I don't understand why should it try to download any models, if it has no models specified. Or why should it try to render anything, if the gazebo client is not launched.
Even an empty world will need the "sun" and "groundplane" (I believe) models. The same happens/happened with the GUI starting. "Or whz should it try to render anything, if the gazebo client is not launched." the issue is not with the "Unable to create X window", that I don't care about / don't need.
Good point. But why to render anything?
I'm not sure I understand your question. Rendering is used for more than just showing you a pretty picture: GPU accelerated plugins, render-to-texture for virtual cameras, etc.
Is there anything non-standard about your display or graphics card? I'm just brainstorming. I don't know the answer, but maybe this can help you figure something out.
I appreciate the effort: no, just a regular nvidia gtx1080. I believe the issue is really with downloading the models.
So can you just download the models into some local folder and use it from there? At least to rule other possible causes out?