Add switch for dxvk-async.

default.nix

@@ -4,6 +4,8 @@
   prefixBaseDir ? "$HOME/.winenix",
   binName ? "starcitizen",
   launcherArgs ? [ "--use-gl=osmesa" ],
+  dxvkPatches ? [ ],
+  dxvkAsync ? false,
   winePackage ? pkgs.wineWowPackages.unstable,
   wineGlobalEnv ? [ "DXVK_STATE_CACHE=0" ],
   winePatches ? [ ./patches/joyaxis.patch ],
@@ -21,9 +23,11 @@ assert !(builtins.any (lib.strings.hasSuffix "/") [ installDir launcherCache pre
 let
   winePkg =  winePackage.overrideAttrs (attrs: {
     patches = attrs.patches ++ winePatches;
-});
+  });
+  dxvk = (pkgsCross.mingwW64.callPackage ./dxvk.nix { async = dxvkAsync;  }).overrideAttrs
+  ( attrs: {  patches = attrs.patches ++ dxvkPatches; });
+  dxvkAsyncEnv = "DXVK_ASYNC=1" ;
 
-  dxvk = (with import ~/repositories/nixpkgs/default.nix {}; pkgsCross.mingwW64.callPackage ./dxvk.nix {  });
   fonts = pkgs.callPackage ./fonts.nix {};
   wine64 = "${winePkg}/bin/wine64";
   wineMulti = "${winePkg}/bin/wine";
@@ -149,7 +153,9 @@ let
     export WINEPREFIX="${prefixBaseDir}/$uuid"
 
     #export all global env vars
-    ${lib.concatMapStrings (x: "export " + x + "\n") wineGlobalEnv }
+      ${lib.concatMapStrings (x: "export " + x + "\n") (wineGlobalEnv
+      ++ lib.lists.optional dxvkAsync  dxvkAsyncEnv
+      )}
 
     #parse input
     case "$@" in

dxvk.nix

@@ -1,15 +1,25 @@
-{ stdenv, lib, fetchFromGitHub, glslang, buildPackages, writeScriptBin, pkgs, pkgsCross }:
+{ stdenv, lib, fetchFromGitHub, fetchpatch, glslang, buildPackages, writeScriptBin, pkgs, pkgsCross,
+  async ? false
+}:
 
 let
     fix = writeScriptBin "x86_64-w64-mingw32-windres" ''
     #!${stdenv.shell}
       exec ${pkgsCross.mingwW64.buildPackages.binutils.bintools}/bin/x86_64-w64-mingw32-windres --preprocessor=x86_64-w64-mingw32-gcc --preprocessor-arg=-E --preprocessor-arg=-xc --preprocessor-arg=-DRC_INVOKED $@
   '';
+  asyncPatch = (fetchpatch {
+    name = "dxvk-async";
+    url = "https://raw.githubusercontent.com/Sporif/dxvk-async/8911d6da0f838efc8fbbea805da522be4e1ad6c3/dxvk-async.patch";
+    sha256 = "0mr43flzim25lfq73pac94ah07yrr86n82fzsx47lxlcmsh9zhrq";
+  });
 
 in stdenv.mkDerivation rec {
   pname = "dxvk";
   version = "1.9";
 
+  patches = []
+    ++ lib.lists.optional async asyncPatch;
+
   src = fetchFromGitHub {
     owner = "doitsujin";
     repo = "dxvk";