Add simple NaCl gamepad example

native_client_sdk/src/examples/gamepad/gamepad.h

+// Copyright (c) 2012 The Native Client Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef EXAMPLES_GAMEPAD_GAMEPAD_H_
+#define EXAMPLES_GAMEPAD_GAMEPAD_H_
+
+#include <map>
+#include <vector>
+#include "ppapi/c/dev/ppb_gamepad_dev.h"
+#include "ppapi/cpp/graphics_2d.h"
+#include "ppapi/cpp/image_data.h"
+#include "ppapi/cpp/instance.h"
+#include "ppapi/cpp/rect.h"
+#include "ppapi/cpp/size.h"
+
+namespace gamepad {
+
+// The Instance class.  One of these exists for each instance of your NaCl
+// module on the web page.  The browser will ask the Module object to create
+// a new Instance for each occurrence of the <embed> tag that has these
+// attributes:
+//     type="application/x-nacl"
+//     nacl="pi_generator.nmf"
+class Gamepad : public pp::Instance {
+ public:
+  explicit Gamepad(PP_Instance instance);
+  virtual ~Gamepad();
+
+  // Update the graphics context to the new size, and regenerate |pixel_buffer_|
+  // to fit the new size as well.
+  virtual void DidChangeView(const pp::Rect& position, const pp::Rect& clip);
+
+  // Flushes its contents of |pixel_buffer_| to the 2D graphics context.
+  void Paint();
+
+  bool quit() const {
+    return quit_;
+  }
+
+  int width() const {
+    return pixel_buffer_ ? pixel_buffer_->size().width() : 0;
+  }
+  int height() const {
+    return pixel_buffer_ ? pixel_buffer_->size().height() : 0;
+  }
+
+  // Indicate whether a flush is pending.  This can only be called from the
+  // main thread; it is not thread safe.
+  bool flush_pending() const {
+    return flush_pending_;
+  }
+  void set_flush_pending(bool flag) {
+    flush_pending_ = flag;
+  }
+
+ private:
+  // Create and initialize the 2D context used for drawing.
+  void CreateContext(const pp::Size& size);
+  // Destroy the 2D drawing context.
+  void DestroyContext();
+  // Push the pixels to the browser, then attempt to flush the 2D context.  If
+  // there is a pending flush on the 2D context, then update the pixels only
+  // and do not flush.
+  void FlushPixelBuffer();
+
+  bool IsContextValid() const {
+    return graphics_2d_context_ != NULL;
+  }
+
+  pp::Graphics2D* graphics_2d_context_;
+  pp::ImageData* pixel_buffer_;
+  const PPB_Gamepad_Dev* gamepad_;
+  bool flush_pending_;
+  bool quit_;
+};
+
+}  // namespace gamepad
+
+#endif  // EXAMPLES_GAMEPAD_GAMEPAD_H_