Summary

A special treatment for 3d models in glb/gltf format is implemented in the Binaries Service. 

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This preview generation happens on the cluster nodes. A Chrome browser instance is started on a virtual framebuffer device. The model is loaded by the browser and then a screenshot of the browser is taken. 

Obtain Sources

The software can be obtained by executing

git clone https://dev.fiz-karlsruhe.de/stash/scm/ddb/3d-screenshot-generator.git

Installation

In order for the scripts to work the follwing following things need to be done on the cluster nodes: 

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sudo yum install npm xorg-x11-server-Xvfb atk java-atk-wrapper at-spi2-atk gtk3 libXt ImageMagick

# Register and start Xvfb service 
sudo echo "
[Unit]
Description=Xvfb headless plotting
After=network.target

[Service]
User=root
ExecStart=/usr/bin/Xvfb :0 -screen 0 1280x1024x24

[Install]
WantedBy=multi-user.target
Alias=Xvfb.service
Alias=xvfbd.service
" > /etc/systemd/system/xvfb.service

sudo systemctl daemon-reload
sudo systemctl enable xvfb
sudo systemctl start xvfb

Configuration and Problem solving

Please always refer to the projects Readme file (especially for CentOS 7 systems). The configuration in appconfig.json needs to be adapted. Please also refer to the projects Readme file, especially for CentOS 7 systems. 

Regular problems

• If some models works and other models don't work, always first check if the timeout setting in appconfig.json is high enough.
• After that don't work, it could be that the puppeteer (Chromium) version is to old for newer generted model version.