Run RawTherapee custom linux build on Windows 10 with sharp fonts on a HiDPI display

Note that this setup may be a moot point as there are important issues when running RT under WSL. One is the overall low performance compared to a Linux in a Virtual Box setup. Another is repeatable freezes of the VM when the contents of the directory currently open in RT are modified on the host. For these and other reasons the Virtual Box setup turned out to be superior to the WSL.

The credit for WSL setup for graphical apps belongs to https://medium.com/@jeffborch/running-the-scenic-elixir-gui-framework-on-windows-10-using-wsl-f9c01fd276f6.

Configure Windows Subsystem for Linux

1. Enable WSL

Settings > Apps > Programs and Features

Check the Windows Subsystem for Linux

2. Install Ubuntu

In Microsoft Store and search for ‘Linux’

Install Ubuntu 20 LTS

3. Install X Server

Run Ubuntu

Run the following commands

sudo apt-get update
sudo apt-get install mesa-utils

Find and download VcXsrv Windows X Server https://sourceforge.net/projects/vcxsrv/

Run XLaunch

Set this config:

Multiple Windows
Display number: 0
Start no client
Uncheck Native OpenGL

Clilck Finish to run the VcXsrv windows xserver.

In Ubuntu terminal run

export DISPLAY=localhost:0

Verify the graphical apps work by running glxgears.

Prepare RawTherapee

For any details refer to https://rawpedia.rawtherapee.com/Linux.

1. Install the build dependencies

In Ubuntu terminal run

sudo apt-get update
sudo apt install build-essential cmake curl git libcanberra-gtk3-dev libexiv2-dev libexpat-dev libfftw3-dev libglibmm-2.4-dev libgtk-3-dev libgtkmm-3.0-dev libiptcdata0-dev libjpeg-dev liblcms2-dev liblensfun-dev libpng-dev librsvg2-dev libsigc++-2.0-dev libtiff5-dev zlib1g-dev

2. Clone the RawTherapee repo

mkdir -p ~/programs
git clone https://github.com/Beep6581/RawTherapee ~/programs/code-rawtherapee
cd ~/programs/code-rawtherapee

3. Select the required branch

git checkout filmneg

4. Compile RawTherapee

cd ~/programs/code-rawtherapee
mkdir build
cd build

cmake \
    -DCMAKE_BUILD_TYPE="release"  \
    -DCACHE_NAME_SUFFIX="5-dev" \
    -DPROC_TARGET_NUMBER="2" \
    -DBUILD_BUNDLE="ON" \
    -DBUNDLE_BASE_INSTALL_DIR="$HOME/programs/rawtherapee" \
    -DOPTION_OMP="ON" \
    -DWITH_LTO="OFF" \
    -DWITH_PROF="OFF" \
    -DWITH_SAN="OFF" \
    -DWITH_SYSTEM_KLT="OFF" \
    ..

make --jobs=$(nproc --all)
make install

5. Run RawTherapee

~/programs/rawtherapee/rawtherapee

At this point RawTherapee should start and work as usual. The Windows drives should be available under /mnt/ directory.

Configure RawTherapee to display sharp fonts

If Windows 10 is configured to use scaling other than 100% (Display -> Scale and Layout), which is typical on a high resolution display, the unsupporting applications will display blurry fonts because their fonts are scaled as raster graphics and not as vector graphics. With the described setup RawTherapee runs under WSL which although is now configured for GUI applications, is not aware of the Windows scaling, so RawTherapee UI fonts look blurry.

1. Configure the XLaunch shortcut

Shutdown the running RawTherapee

Shutdown VcXsrv by right-clicking its tray icon and selecting Exit

Right-click the XLaunch icon and select Properties

On Compatibility tab select Change high DPI settings

In High DPI scaling override section set the checkbox and select Application in the dropdown

Close the dialogs by clicking Ok

2. Configure RawTherapee for HiDPI display

Run RawTherapee

Open Preferences

On General tab enable Pseudo-HiDPI mode

Restart RawTherapee

Now RawTherapee UI should display sharp fonts everywhere and the layout should be comfortably scaled. If the fonts appear too small, their size can be adjusted in Preferences.

nicnilov/doc.md