nongnu: Add dxvk.

* nongnu/packages/wine.scm (dxvk): New variable.

nongnu/packages/wine.scm

@@ -76,3 +76,51 @@ It has a menu of supported games/apps for which it can do all the workarounds
 automatically.  It also allows the installation of missing nonfree DLLs and
 tweaking of various Wine settings.")
     (license license:lgpl2.1)))
+
+;; TODO: We could package from source and distribute in upstream Guix.
+;; See bug #35031.
+(define-public dxvk
+  (package
+    (name "dxvk")
+    (version "1.2.1")
+    (source (origin
+              (method url-fetch)
+              (uri (string-append "https://github.com/doitsujin/dxvk/releases/download/v"
+                                  version "/dxvk-" version ".tar.gz"))
+              (sha256
+               (base32
+                "1aix9isys8n0hp8vwrmm4c58716g6famsm62x40z24sdlfhfqaqr"))))
+    (build-system trivial-build-system)
+    (native-inputs
+     `(("gzip" ,gzip)
+       ("tar" ,tar)))
+    (inputs
+     `(("wine" ,wine64)
+       ("bash" ,bash-minimal)))
+    (arguments
+     `(#:modules ((guix build utils))
+       #:builder
+       (begin
+         (use-modules (guix build utils))
+         (let ((out (assoc-ref %outputs "out"))
+               (bash (assoc-ref %build-inputs "bash")))
+           (setenv "PATH" (string-append
+                           (assoc-ref %build-inputs "gzip") "/bin:"
+                           (assoc-ref %build-inputs "tar") "/bin"))
+           (invoke "tar" "xvf" (assoc-ref %build-inputs "source"))
+           (mkdir-p out)
+           (copy-recursively (string-append ,name "-" ,version "/") out)
+           (chdir out)
+           (mkdir-p "bin")
+           (rename-file "setup_dxvk.sh" "bin/setup_dxvk")
+           (patch-shebang "bin/setup_dxvk" (list (string-append bash "/bin")))
+           (substitute* "bin/setup_dxvk"
+             (("wine=\"wine\"")
+              (string-append "wine=" (assoc-ref %build-inputs "wine") "/bin/wine"))
+             (("x32") "../x32")
+             (("x64") "../x64")))
+         #t)))
+    (home-page "https://github.com/doitsujin/dxvk/")
+    (synopsis "Vulkan-based D3D11 and D3D10 implementation for Wine")
+    (description "Vulkan-based D3D11 and D3D10 implementation for Wine.")
+    (license license:zlib)))