multi touch handling on android

amumurst · Sep 30, 2016 · 7804a72 · 7804a72
1 parent ae45dce
commit 7804a72
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Showing 2 changed files with 33 additions and 3 deletions.
diff --git a/android/src/main/scala/sgl/android/AndroidInputProvider.scala b/android/src/main/scala/sgl/android/AndroidInputProvider.scala
@@ -19,12 +19,26 @@ trait AndroidInputProvider extends InputProvider with Lifecycle {
       override def onTouch(view: View, event: MotionEvent): Boolean = {
         gestureDetector.onTouchEvent(event)
 
+        /*
+         * Multi-touch on android starts with a first ACTION_DOWN event for the
+         * very first pointer, then following down are ACTION_POINTER_DOWN, and 
+         * first up (as long as one finger is still left) is ACTION_POINTER_UP.
+         * Seems like we don't need that level of precision in the engine, so we
+         * only have the notion of Up and Down, relying on the pointer id if we
+         * need to track a multitouch gesture
+         */
+
+        val action = event.getActionMasked
         for(p <- 0 until event.getPointerCount()) {
-          if(event.getAction == MotionEvent.ACTION_DOWN) {
+          if(action == MotionEvent.ACTION_DOWN) {
             val x = event.getX(p).toInt
             val y = event.getY(p).toInt
             Input.newEvent(Input.TouchDownEvent(x, y, event.getPointerId(p)))
-          } else if(event.getAction == MotionEvent.ACTION_MOVE) {
+          } else if(action == MotionEvent.ACTION_POINTER_DOWN) {
+            val x = event.getX(p).toInt
+            val y = event.getY(p).toInt
+            Input.newEvent(Input.TouchDownEvent(x, y, event.getPointerId(p)))
+          } else if(action == MotionEvent.ACTION_MOVE) {
 
             //ACTION_MOVE is sometimes batched, meaning that we need to consume
             //historical data from the event, that shows intermediate position
@@ -38,7 +52,11 @@ trait AndroidInputProvider extends InputProvider with Lifecycle {
             val x = event.getX(p).toInt
             val y = event.getY(p).toInt
             Input.newEvent(Input.TouchMovedEvent(x, y, event.getPointerId(p)))
-          } else if(event.getAction == MotionEvent.ACTION_UP) {
+          } else if(action == MotionEvent.ACTION_POINTER_UP) {
+            val x = event.getX(p).toInt
+            val y = event.getY(p).toInt
+            Input.newEvent(Input.TouchUpEvent(x, y, event.getPointerId(p)))
+          } else if(action == MotionEvent.ACTION_UP) {
             val x = event.getX(p).toInt
             val y = event.getY(p).toInt
             Input.newEvent(Input.TouchUpEvent(x, y, event.getPointerId(p)))

diff --git a/core/src/main/scala/sgl/InputHelpers.scala b/core/src/main/scala/sgl/InputHelpers.scala
@@ -18,7 +18,17 @@ trait InputHelpersComponent extends Lifecycle {
       ev foreach processEvent
       ev
     }
+    def processEvents(function: (InputEvent) => Unit): Unit = {
+      var oev = Input.pollEvent()
+      while(!oev.isEmpty) {
+        val ev = oev.get
+        processEvent(ev)
+        function(ev)
+        oev = pollEvent()
+      }
+    }
 
+    //TODO: not a good name, confusing with processEvents 
     /** Process an input event to maintain state of inputs */
     def processEvent(event: InputEvent): Unit = event match {
       case KeyDownEvent(key) => setKeyboardState(key, true)
@@ -185,6 +195,8 @@ trait InputHelpersComponent extends Lifecycle {
       /** is defined if at least one pointer is pressed */
       def pressed: Option[(Int, Int)] = pointerPressed.toSeq.headOption.map(_._2)
       def pressed(pointer: Int): Option[(Int, Int)] = pointerPressed.get(pointer)
+
+      def allPressed: Seq[(Int, (Int, Int))] = pointerPressed.toSeq
     }
 
     object Mouse {