Rhyolite-MELTS (or other software) display is tiny on high-resolution screen

[Paula]

If you followed the instructions for Enabling the Windows Subsystem for Linux and installing the Rhyolite-MELTS GUI post (original or updated) on a laptop with a high-resolution screen, such as the Surface, you may find that the rhyoliteMELTS display looks tiny.

Most Windows X server software, including Xming, incorrectly reports to Windows that it is able to deal with the high resolution. The problem is not restricted to X. Other software, such as Adobe Illustrator, Photoshop, CorelDraw and Dreamweaver have shown similar behavior. A workaround involves adding a text file (the 'manifest') and telling Windows to handle the application scaling for the high resolution screen. The external manifest hack requires admin access.

If your X server is X410, then the external manifest hack does not work. This is by design so that Linux software that can deal with scaling for a high resolution screen are allowed to do so (see Running X410 on HiDPI Screens). There is no way to make the rhyolite-MELTS GUI run in a high-resolution mode, but since x410 version 2 was released it has an option to fix the scaling so there is no need to install additional software. Scroll down to the 'Built-in DPI Scaling' section of Running X410 on HiDPI Screens. For rhyolite-MELTS try the 'Default' setting first, but if this does not work (x410 crashes), then try 'High Quality'; for other software you will probably be able to use 'High Quality'. See other Howto entries on the Choung Networks site for more details.[/i]

There is also a way to run rhyolite-MELTS (actually xterm, which is then used to open rhyolite-MELTS) with a user-defined scaling. This alternative workaround does not require admin access but only works for ubuntu 18.04 LTS (the current ubuntu app). It may be of use for other X servers (i.e. not Xming or x410) so it is described in a separate post.

The method for Xming outlined here borrows from write-ups by scrambler, Luis, and Dan Antonielli. This version uses the command line (cmd.exe) so that you can copy and paste the commands. If you do not have admin access, or are not comfortable with editting the registry, you can use Windows' Ease of Access tools as a workaround; scroll down to the bottom for this alternative.

External Manifest file (requires admin access)

First we need to open cmd.exe as an Administrator. You can find 'Command Prompt' it in the Start Menu, under 'Windows System'. Right-click 'Command Prompt', then 'More', then 'Run as administrator'. Or right-click the Start button, then 'Run', then type 'cmd.exe'; then right-click the Command Prompt icon in the task bar, then right-click 'Command Prompt' and 'Run as administrator'. You may need to select 'Yes' and/or enter your Windows password.

The Command Prompt will open in the C:\Windows\system32 directory. First navigate to a folder in your home space, somewhere to put a backup file that you will be able to find. For example, 'cd C:\Users\your_username\folder_name'. Next right-click where is says 'Administrator: Command Prompt' at the top of the window and choose 'Properties'. Make sure 'Enable Ctrl key shortcuts' is checked. You can now copy (control-C) and paste (control-V) commands from here to the command line.

reg export HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\SideBySide sidebyside.reg /y

... this backs up the relevant Registry key
... in the unlikely event that something does not work just double-click the 'sidebyside.reg' file to restore the previous state

reg add HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\SideBySide /v PreferExternalManifest /t REG_DWORD /d 0x1

... this tells Windows to look in an external file (if available) to see whether a given application can handle the high-resolution screen

Download the manifest.txt file from Dan Antonielli's page. The next instructions assume that your browser saves files in 'Downloads' and that you installed Xming in the default location, but you can adjust accordingly:

cd C:\Users\your_username\Downloads
copy manifest.txt "C:\Program Files\Xming\Xming.exe.manifest"

You can use the same file trick for other software by replacing 'Program Files' with 'Programs Files (x86)', if appropriate, '\Xming\' with the installation folder, and 'Xming.exe.manifest' with the executable name+'.manifest'. For example:

Photoshop	photoshop.exe.manifest
Illustrator	illustrator.exe.manifest
Dreamweaver	dreamweaver.exe.manifest
CorelDraw (home edition)	drawhome.exe.manifest

Using Magnifier (does not require admin access)

Open Settings (click either the Start button in the bottom LH corner or the Notification icon bottom RH corner; then click the cog icon). Type 'Magnifier settings' in the search box. Reduce the Zoom level increments to 25%. You can experiment with the Magnification zoom level but something in the range 150 - 200% is likely to work. You probably want to leave the 'Start Magnifier...' boxes unchecked and put the Magnifier mode in 'Full Screen'. Turn the Magnifier on, scroll down and right-click the Magnifier icon and choose 'Pin to taskbar'. Now if you turn off the Magnifier (by clicking the 'X' in the top RH corner of the Magnifier popup), you can easily turn it on again by selecting it from the taskbar; the cog on the Magnifier popup is a shortcut to the Settings page.

Paula