Remote access and online data

Online genomes and files

GW loads online reference genomes directly — when GW starts without a reference, a terminal picker lists the online genomes (type a number or a tag such as hg38). The same catalogue is browsable from the ImGui file dialogs, which can also download remote data into a session.

The online command prints links for the current region in online genome browsers:

online        # using the loaded genome tag
online hg19

UCSC tables

The online files dialog (top menu → Online files) includes a Search UCSC interface. Enter an assembly (e.g. hg38) and a search term to query UCSC table tracks directly:

• Matching tracks are listed with their name, assembly and description
• Select a track and click Download to fetch it as a local BED file, which GW then draws as a track
• Some results are only available as a raw table dump — these download but cannot be drawn

This is the quickest way to pull annotation tracks (genes, repeats, regulatory features and more) from UCSC into a GW session without leaving the app.

Direct remote data access

GW reads remote data over HTTP/HTTPS or FTP. Provide full URLs:

gw https://example.org/ref.fa -b https://example.org/your.bam -r chr1

Secure access

For data behind SSH authentication:

SSHFS mount

Mount the remote directory locally so GW sees remote files as local. macOS: install macFuse. Linux/Windows: SSHFS guide.

X11 forwarding

ssh -X username@remote-server
gw --delay 100   # add delay (ms) to handle latency

Best between Linux systems; Mac-to-Linux mostly does not work.

Xpra

Better performance than X11, supports multiple users:

xpra start :100 --start="gw ref.fa -b your.bam -r chr1:50000-60000" --sharing=yes --daemon=no
xpra attach ssh:username@remote-server:100

Custom SSH: xpra attach ssh:username@remote-server:100 --ssh "ssh -o IdentitiesOnly=yes -i /path/to/key.pem".

VNC

Full remote desktop (e.g. TigerVNC). Requires administrator setup on the server.

Comparison

Method	Performance	Setup	Best for
SSHFS	Good	Low	Direct file access
X11	Fair	Low	Quick access, Linux-to-Linux
Xpra	Excellent	Medium	Regular remote usage
VNC	Good	High	Full desktop

Embedding GW in web apps (v2)

GW v2 adds a versioned remote viewer protocol (JSON over HTTP/WebSocket) with a WASM build of the renderer — embed GW views in web apps and drive them remotely, no X11 or VNC needed. See API & integrations.

Graphics troubleshooting

Check OpenGL with glxinfo | grep "direct rendering" (install mesa-utils if missing). Expect direct rendering: Yes and OpenGL 2.0+. Test rendering with glxgears.

• Blank/black window: export LIBGL_ALWAYS_SOFTWARE=1
• Slow over X11: increase the delay, e.g. gw --delay 200
• Connection refused: check ssh -v username@remote-server and X11Forwarding yes in /etc/ssh/sshd_config
• Display export errors: check echo $DISPLAY; set export DISPLAY=:0 if missing