README_WINDOWS.md

Building MyPaint on Windows

Setup.exe and standalone

The windows subdirectory contains scripting for making a Win32 installer from git. This may be all you need to build MyPaint from source on Windows. See windows/README.md for detailed instructions.

The remainder of this document describes a manual process intended for developers and testers.

Manual building and testing

This document describes building a native Win32 MyPaint using MSYS2's MinGW-w64. The resultant script and its extension DLL must be run with MSYS2's own Python build for the target system (/mingw32 or /mingw64). Running it depends on external libs like GTK3 packaged by the MSYS2 team, all of which are also installed into the target system.

The only supported method for running MyPaint with these instructions is from the command line.

This doc DOES NOT COVER building MyPaint into an installer bundle See windows/README.md if you want to do that. This document covers only the bare essentials needed to get MyPaint running for debugging purposes.

Install MSYS2

MSYS2 is a free toolchain, build environment, and binary library distribution for Windows. It can create native PE32 binaries for Windows using the MinGW-w64 compiler.

To install MSYS2, download it and follow the installation instructions at https://msys2.github.io/.

When making and these instructions, I started by downloading and running msys2-x86_64-20150916.exe. I installed MSYS2 to the normal C:\msys64 location with all the default options.

Update MSYS2

Once the installer finishes, update MSYS2 from the MSYS environment.

This is launched using the “MSYS2 Shell” shortcut in the start menu. Alternatively, you can run C:\msys64\msys2_shell.bat. If you let it run automatically, you'll see this shell by default.

Run update-core at the “$” prompt to upgrade the core packages. Press the return key after typing the nane of the command, and it will start running.

update-core

You now MUST close ALL MSYS2 windows using their top-right X button. Before you can update the rest of MSYS2, it needs to be cleanly started again.

pacman -Su

No need to restart after this second phase of the update.

Build environments

The build commands below must be run in the environment which gives you the correct path for the target architecture and prefix you will be compiling for. These are:

• MINGW32:
  • creates Win32 executables in /mingw32 (C:\msys64\mingw32)
  • start menu: “MinGW-w64 Win32 Shell”
  • launcher script: C:\msys64\mingw32_shell.bat
• MINGW64:
  • creates Win64 executables in /mingw64 (C:\msys64\mingw64)
  • start menu: “MinGW-w64 Win64 Shell”
  • launcher script: C:\msys64\mingw64_shell.bat

The text in bold refers to what you see in the prompt. I'll use those names to refer to the environments below. The only real difference between the three environments is the PATH environment variable.

Get a development copy of MyPaint

You'll need the MSYS2 git first. In any MSYS2 environment, issue

pacman -S git

Once that's done, clone MyPaint, and make sure all its submodules are present in the source tree. These commands will work in any MSYS2 environment.

cd /usr/src
git clone https://github.com/mypaint/mypaint.git
cd mypaint
git submodule update --init

The /usr/src prefix above is just a convention. You can put the cloned repository anywhere.

Install MyPaint's dependencies

All of MyPaint's dependencies are available from the MSYS2 repositories. Thanks to everyone maintaining MINGW-packages for giving us a great open platform to build against!

To install MyPaint's dependencies, start MSYS2's MINGW32 or MINGW64 shell. There's a script for installing the dependency packages in the windows/ folder of the source tree:

cd /usr/src/mypaint
windows/install-msys2-deps.sh

Build and test MyPaint

Start by fetching and building MyPaint. You need to do this from the MINGW32 or MINGW64 environment you fetched the dependencies for.

cd /usr/src/mypaint
scons

The "scons" used here is actually the MSYS environment's scons. We have several nasty hacks in our SCons scripting to make this work, but this combination is what the official builds use.

Hopefully after this, you will be able to run MyPaint from the location you pulled it down to:

cd /usr/src/mypaint
MYPAINT_DEBUG=1 ./mypaint -c /tmp/cfgtmp1

MyPaint may be quite a bit more buggy on the Windows platform than on the Linux platform, be warned.

Known Problems

• No pressure support / glitches with tablet drivers. These should be reported to the GDK maintainers. See https://bugzilla.gnome.org/show_bug.cgi?id=743330 for an example of how to do this effectively. Discussing your issue on IRC after raising it in the tracker is often very fruitful too.

• Bugs. Lots of them. The port to Windows has historically received the least love of all MyPaint ports, but this document is intended to help address that. The number is diminishing, and MyPaint runs on native Windows reasonably well now. We really need actively testing users to improve support further. Please report problems as described in CONTRIBUTING.md.