ue4: init at 4.10.2

This builds Unreal Engine 4 and has a wrapper to start the editor.

Sadly the application requires write access to a lot of paths. I have a
hack to do a symlink tree under $HOME and it works well, the UE4Editor
binary just needs to be not a symlink.

pkgs/games/ue4/default.nix

@@ -0,0 +1,82 @@
+{ stdenv, writeScript, fetchurl, requireFile, unzip, clang_35, mono, which,
+  xorg, xdg-user-dirs }:
+
+let
+  inherit (stdenv) lib;
+  deps = import ./cdn-deps.nix { inherit fetchurl; };
+  linkDeps = writeScript "link-deps.sh" (lib.concatMapStringsSep "\n" (hash:
+    let prefix = lib.concatStrings (lib.take 2 (lib.stringToCharacters hash));
+    in ''
+      mkdir -p .git/ue4-gitdeps/${prefix}
+      ln -s ${lib.getAttr hash deps} .git/ue4-gitdeps/${prefix}/${hash}
+    ''
+  ) (lib.attrNames deps));
+  libPath = stdenv.lib.makeLibraryPath [
+    xorg.libX11 xorg.libXScrnSaver xorg.libXau xorg.libXcursor xorg.libXext
+    xorg.libXfixes xorg.libXi xorg.libXrandr xorg.libXrender xorg.libXxf86vm
+    xorg.libxcb
+  ];
+in
+stdenv.mkDerivation rec {
+  name = "ue4-${version}";
+  version = "4.10.2";
+  sourceRoot = "UnrealEngine-${version}-release";
+  src = requireFile {
+    name = "${sourceRoot}.zip";
+    url = "https://github.com/EpicGames/UnrealEngine/releases/tag/${version}";
+    sha256 = "1rh6r2z00kjzq1i2235py65bg9i482az4rwr14kq9n4slr60wkk1";
+  };
+  unpackPhase = ''
+    ${unzip}/bin/unzip $src
+  '';
+  configurePhase = ''
+    ${linkDeps}
+
+    # Sometimes mono segfaults and things start downloading instead of being
+    # deterministic. Let's just fail in that case.
+    export http_proxy="nodownloads"
+
+    patchShebangs Setup.sh
+    patchShebangs Engine/Build/BatchFiles/Linux
+    ./Setup.sh
+    ./GenerateProjectFiles.sh
+  '';
+
+  installPhase = ''
+    mkdir -p $out/bin $out/share/UnrealEngine
+
+    sharedir="$out/share/UnrealEngine"
+
+    cat << EOF > $out/bin/UE4Editor
+    #! $SHELL -e
+
+    sharedir="$sharedir"
+
+    # Can't include spaces, so can't piggy-back off the other Unreal directory.
+    workdir="\$HOME/.config/unreal-engine-nix-workdir"
+    if [ ! -e "\$workdir" ]; then
+      mkdir -p "\$workdir"
+      ${xorg.lndir}/bin/lndir "\$sharedir" "\$workdir"
+      unlink "\$workdir/Engine/Binaries/Linux/UE4Editor"
+      cp "\$sharedir/Engine/Binaries/Linux/UE4Editor" "\$workdir/Engine/Binaries/Linux/UE4Editor"
+    fi
+
+    cd "\$workdir/Engine/Binaries/Linux"
+    export PATH="${xdg-user-dirs}/bin\''${PATH:+:}\$PATH"
+    export LD_LIBRARY_PATH="${libPath}\''${LD_LIBRARY_PATH:+:}\$LD_LIBRARY_PATH"
+    exec ./UE4Editor "\$@"
+    EOF
+    chmod +x $out/bin/UE4Editor
+
+    cp -r . "$sharedir"
+  '';
+  buildInputs = [ clang_35 mono which xdg-user-dirs ];
+
+  meta = {
+    description = "A suite of integrated tools for game developers to design and build games, simulations, and visualizations";
+    homepage = https://www.unrealengine.com/what-is-unreal-engine-4;
+    license = stdenv.lib.licenses.unfree;
+    platforms = stdenv.lib.platforms.linux;
+    maintainers = [ stdenv.lib.maintainers.puffnfresh ];
+  };
+}

pkgs/games/ue4/generate-expr-from-cdn.sh

@@ -0,0 +1,37 @@
+#!/bin/sh
+
+go() {
+    file="$1"
+
+    IFS=$'\n'
+    for pack in $(perl -n -e '/(<Pack .*\/>)/ && print "$1\n"' $file); do
+        remotepath=$(echo "$pack" | perl -n -e '/RemotePath="([^"]*)"/ && print $1')
+        hash=$(echo "$pack" | perl -n -e '/Hash="([^"]*)"/ && print $1')
+        url="http://cdn.unrealengine.com/dependencies/$remotepath/$hash"
+
+        until sha256=$(nix-prefetch-url $url --type sha256); do
+            true
+        done
+
+        cat <<EOF
+  "$hash" = fetchurl {
+    url = $url;
+    sha256 = "$sha256";
+  };
+EOF
+    done
+}
+
+
+cat <<EOF
+{ fetchurl }:
+
+{
+EOF
+
+go Engine/Build/Commit.gitdeps.xml
+go Engine/Build/Promoted.gitdeps.xml
+
+cat <<EOF
+}
+EOF

pkgs/top-level/all-packages.nix

@@ -14619,6 +14619,8 @@ let
 
   urbanterror = callPackage ../games/urbanterror { };
 
+  ue4 = callPackage ../games/ue4 { };
+
   ue4demos = recurseIntoAttrs (callPackage ../games/ue4demos { });
 
   ut2004demo = callPackage ../games/ut2004demo { };