GN

GN is a new meta-build system originally designed to replace GYP in Chromium.

You can build Skia using GN in a limited number of configurations. We expect that as that limited number rises, GN will become the preferred, and then only, way to build Skia.

Supported Features

* Linux, Mac, Android
* Software and GL rendering
* libskia.a, libskia.so
* DM, nanobench

Quickstart

Please check out Skia using the instructions in one of the other quick start guides. We diverge where they'd first run some command with "gyp" in it.

# After gclient sync, run fetch-gn to make sure you have GN.
gclient sync && bin/fetch-gn

# Run GN to generate your build files.  Some examples.
gn gen out/Debug
gn gen out/Release  --args='is_debug=false'
gn gen out/Clang    --args='cc="clang" cxx="clang++"'
gn gen out/Shared   --args='is_component_build=true'
gn gen out/Cached   --args='compiler_prefix="ccache"'
gn gen out/Stripped --args='extra_cflags="-g0"'
gn gen out/RTTI     --args='extra_cflags_cc="-frtti"'

# Build
ninja -C out/Debug
ninja -C out/Release
ninja -C out/Clang
ninja -C out/Shared
ninja -C out/Cached
ninja -C out/Stripped
ninja -C out/RTTI

From here everything is pretty much business as usual.

Android

To build Skia for Android you need an Android NDK.

If you do not have an NDK and have access to CIPD, you can use one of these commands to fetch the NDK our bots use:

python infra/bots/assets/android_ndk_linux/download.py  -t /tmp/ndk
python infra/bots/assets/android_ndk_darwin/download.py -t /tmp/ndk

When generating your GN build files, pass the path to your ndk and your desired target_cpu:

gn gen out/arm      --args='ndk="/tmp/ndk" target_cpu="arm"'
gn gen out/arm64    --args='ndk="/tmp/ndk" target_cpu="arm64"'
gn gen out/mips64el --args='ndk="/tmp/ndk" target_cpu="mips64el"'
gn gen out/mipsel   --args='ndk="/tmp/ndk" target_cpu="mipsel"'
gn gen out/x64      --args='ndk="/tmp/ndk" target_cpu="x64"'
gn gen out/x86      --args='ndk="/tmp/ndk" target_cpu="x86"'

Other arguments like is_debug and is_component_build continue to work.

To test on a locally connected Android device, you can use our droid convenience script:

ninja -C out/arm64
bin/droid out/arm64/dm --src gm --config gpu