update build for jdk 12

build.sbt

@@ -2,6 +2,17 @@ import Dependencies._
 import Helpers._
 import Resolvers._
 
+// Determine OS version of JavaFX binaries
+lazy val osName = System.getProperty("os.name") match {
+  case n if n.startsWith("Linux")   => "linux"
+  case n if n.startsWith("Mac")     => "mac"
+  case n if n.startsWith("Windows") => "win"
+  case _ => throw new Exception("Unknown platform!")
+}
+
+// Add dependency on JavaFX libraries, OS dependent
+lazy val javaFXModules = Seq("base", "controls", "fxml", "graphics", "media", "swing", "web")
+
 lazy val root = (project in file ("."))
   .enablePlugins(BasicSettings, SiteSettingsPlugin)
   .settings(Publish.settings: _*)
@@ -23,6 +34,10 @@ lazy val root = (project in file ("."))
       shapeless
     ),
 
+	libraryDependencies ++= javaFXModules.map( m =>
+	  "org.openjfx" % s"javafx-$m" % "12.0.2" classifier osName
+	),
+
     /* Akka dependencies */
     libraryDependencies ++= Seq (
       akkaActor       % "optional",