added showcase for writing an image to a file

jvm/src/main/scala/doctus/jvm/impl/DoctusFxImpl.scala

@@ -15,11 +15,15 @@ private[jvm] trait DoctusCanvasFxImpl extends DoctusCanvas {
   def comp: Canvas
 
   comp.widthProperty.addListener(new ChangeListener[Number] {
-    def changed(obs: ObservableValue[_ <: Number], old: Number, nev: Number) { repaint() }
+    def changed(obs: ObservableValue[_ <: Number], old: Number, nev: Number) {
+      repaint()
+    }
   })
-  
+
   comp.heightProperty().addListener(new ChangeListener[Number] {
-    def changed(obs: ObservableValue[_ <: Number], old: Number, nev: Number) { repaint() }
+    def changed(obs: ObservableValue[_ <: Number], old: Number, nev: Number) {
+      repaint()
+    }
   })
 
   val g = comp.getGraphicsContext2D
@@ -35,13 +39,19 @@ private[jvm] trait DoctusCanvasFxImpl extends DoctusCanvas {
     paintFun match {
       case Some(f) =>
         val dg = DoctusGraphicsFx(g)
-        Platform.runLater(new Runnable {
-          def run() = f(dg)
-        })
+        if (Platform.isFxApplicationThread) {
+          f(dg)
+        } else {
+          Platform.runLater(new Runnable {
+            def run() = f(dg)
+          })
+        }
       case None => // Nothing to do
     }
   }
+
   def width: Int = comp.getWidth.toInt
+
   def height: Int = comp.getHeight.toInt
 
 }
@@ -51,6 +61,7 @@ private[jvm] trait DoctusPointableFxImpl extends DoctusPointable {
   def comp: Node
 
   def onStart(f: DoctusPoint ⇒ Unit): Unit = _onStart = Some(f)
+
   def onStop(f: DoctusPoint ⇒ Unit): Unit = _onStop = Some(f)
 
   var _onStart = Option.empty[DoctusPoint ⇒ Unit]
@@ -82,6 +93,7 @@ private[jvm] trait DoctusDraggableFxImpl extends DoctusDraggable {
 
   // Members declared in doctus.core.DoctusPointable
   def onStart(f: DoctusPoint ⇒ Unit): Unit = _onStart = Some(f)
+
   def onStop(f: DoctusPoint ⇒ Unit): Unit = _onStop = Some(f)
 
   comp.setOnMouseDragEntered(DoctusJvmUtil.handler { e =>
@@ -115,12 +127,12 @@ private[jvm] trait DoctusDraggableFxImpl extends DoctusDraggable {
 }
 
 /**
- * Listens to the keyboard.
- */
+  * Listens to the keyboard.
+  */
 private[jvm] trait DoctusKeyFxImp extends DoctusKey {
 
   comp.setFocusTraversable(true)
-  
+
   def comp: Node
 
   var _onKeyPressed = Option.empty[DoctusKeyCode ⇒ Unit]

showcase-jvm/src/main/scala/doctus/jvm/ShowcaseTemplateJvmFileStillImage.scala

@@ -0,0 +1,54 @@
+package doctus.jvm
+
+import java.io.File
+import javafx.application.Application
+import javafx.embed.swing.SwingFXUtils
+import javafx.scene._
+import javafx.scene.canvas.Canvas
+import javafx.stage.Stage
+import javax.imageio.ImageIO
+
+import doctus.core._
+import doctus.core.template.DoctusTemplateController
+
+object ShowcaseTemplateJvmFileStillImage extends App {
+
+  Application.launch(classOf[FxApp], args: _*)
+
+  class FxApp extends Application {
+
+    val homeDir = new File(System.getProperty("user.home"))
+    val pngFile = new File(homeDir, "ShowcaseTemplateJvmFileStillImage.png")
+
+    override def start(stage1: Stage) {
+
+      val width = 3000
+      val height = 2000
+
+      val canvas = new Canvas(width, height)
+
+      val doctCanvas = DoctusTemplateCanvasFx(canvas)
+      val doctSched = DoctusSchedulerJvm
+
+      val grp = new Group()
+      grp.getChildren.add(canvas)
+
+      // Start the controller
+      val templ = DoctusTemplateStillImage(doctCanvas)
+      DoctusTemplateController(templ, doctSched, doctCanvas)
+      doctCanvas.repaint()
+
+      val wi = grp.snapshot(new SnapshotParameters(), null)
+      require(wi != null)
+      val bi = SwingFXUtils.fromFXImage(wi, null)
+      require(bi != null)
+      ImageIO.write(bi, "png", pngFile)
+
+      println("wrote image to '%s'" format pngFile)
+      System.exit(0)
+
+    }
+  }
+
+}
+