begin binding gamepad functions from GLFW to SML

ffi/glfw-input.c

@@ -40,3 +40,29 @@ void setKeyCallback(GLFWwindow *window) {
   glfwSetKeyCallback(window, keyCallback);
 }
 
+// gamepad code
+GLFWgamepadstate state;
+float* axes;
+int axesCount = -1;
+
+void getGamepadState(int joystickID) {
+  if (glfwGetGamepadState(joystickID, &state)) {
+    axes = glfwGetJoystickAxes(joystickID, &axesCount);
+  }
+}
+
+float getLeftJoystickXAxisState() {
+  if (axesCount >= 2) {
+    return axes[0];
+  } else {
+    return 99.0;
+  }
+}
+
+float getLeftJoystickYAxisState() {
+  if (axesCount >= 2) {
+    return axes[1];
+  } else {
+    return 99.0;
+  }
+}

ffi/glfw-input.sml

@@ -52,4 +52,12 @@ struct
   val (KEY_ARROW_DOWN, _) =
     _symbol "KEY_ARROW_DOWN" public : ( unit -> int ) * ( int -> unit );
   val KEY_ARROW_DOWN = KEY_ARROW_DOWN ()
+
+  val getGamepadState =
+    _import "getGamepadState" public : int -> unit;
+
+  val getLeftJoystickXAxisState =
+    _import "getLeftJoystickXAxisState" public : unit -> Real32.real;
+  val getLeftJoystickYAxisState =
+    _import "getLeftJoystickYAxisState" public : unit -> Real32.real;
 end

shell/gl-draw.sml

@@ -145,6 +145,28 @@ struct
       updateLoop (0, InputMailbox.getMessagesAndClear (), app)
   end
 
+fun getGamepadState () =
+  let
+    val () = Input.getGamepadState 0
+    val () = Input.getGamepadState 1
+    val () = Input.getGamepadState 2
+    val () = Input.getGamepadState 3
+    val () = Input.getGamepadState 4
+    val () = Input.getGamepadState 5
+    val () = Input.getGamepadState 6
+    val () = Input.getGamepadState 7
+    val () = Input.getGamepadState 8
+    val () = Input.getGamepadState 9
+    val () = Input.getGamepadState 10
+    val () = Input.getGamepadState 11
+    val () = Input.getGamepadState 12
+    val () = Input.getGamepadState 13
+    val () = Input.getGamepadState 14
+    val () = Input.getGamepadState 15
+  in
+    ()
+  end
+
   fun helpLoop (app, shellState as {window, ...}: t) =
     case Glfw.windowShouldClose window of
       false =>
@@ -154,6 +176,13 @@ struct
           val _ = Gles3.clearColor (0.89, 0.89, 0.89, 1.0)
           val _ = Gles3.clear ()
 
+          val () = getGamepadState ()
+          val xAxis = Input.getLeftJoystickXAxisState ()
+          val yAxis = Input.getLeftJoystickYAxisState ()
+          val () = print ("x axis = " ^ Real32.toString xAxis ^ "\n")
+          val () = print ("y axis = " ^ Real32.toString yAxis ^ "\n")
+          val () = print "\n"
+
           val app = update app
           val _ = draw shellState
 

todo.md

@@ -1,3 +1,4 @@
 # To-do list
+- Bind gamepad functions from GLFW
 - Modify deletion functions to use `PersistentVector.delete` 
 - Implement 'yj' motion and add tests for it