cocos2d-x3.0 touch研究

看来得好好研究下touch事件，非常重要的一个东东，因为智能手机经常要发生touch交互。

我们看下cocos2d-x里面是如何实现touch事件的注册和分发的：

首先看这个函数：

GLFWAPI GLFWmousebuttonfun glfwSetMouseButtonCallback(GLFWwindow* window, GLFWmousebuttonfun cbfun);

是opengl的API：

但它是如何被调到的呢：

首先是

int APIENTRY _tWinMain(HINSTANCE hInstance,
                       HINSTANCE hPrevInstance,
                       LPTSTR    lpCmdLine,
                       int       nCmdShow)
{
    UNREFERENCED_PARAMETER(hPrevInstance);
    UNREFERENCED_PARAMETER(lpCmdLine);

    // create the application instance
    AppDelegate app;
    EGLView eglView;
    eglView.init("TestCPP",400,800);
    return Application::getInstance()->run();//这里注意run
}

int Application::run()
{
    PVRFrameEnableControlWindow(false);

    // Main message loop:
    LARGE_INTEGER nFreq;
    LARGE_INTEGER nLast;
    LARGE_INTEGER nNow;

    QueryPerformanceFrequency(&nFreq);
    QueryPerformanceCounter(&nLast);

    // Initialize instance and cocos2d.
    if (!applicationDidFinishLaunching())
    {
        return 0;
    }

    EGLView* pMainWnd = EGLView::getInstance();//新建一个EGLView类

EGLView构造的时候会调用：

bool EGLView::init(const char* viewName, float width, float height, float frameZoomFactor)
{
    if(nullptr != _mainWindow) return true;

    setViewName(viewName);
    setFrameSize(width, height);
    setFrameZoomFactor(frameZoomFactor);
    
    glfwWindowHint(GLFW_RESIZABLE,GL_FALSE);
    _mainWindow = glfwCreateWindow(_screenSize.width * _frameZoomFactor, _screenSize.height * _frameZoomFactor, _viewName, nullptr, nullptr);
    glfwMakeContextCurrent(_mainWindow);
    
    glfwGetFramebufferSize(_mainWindow, &_frameBufferSize[0], &_frameBufferSize[1]);
    glfwSetMouseButtonCallback(_mainWindow,EGLViewEventHandler::OnGLFWMouseCallBack);//注意这里
    glfwSetCursorPosCallback(_mainWindow,EGLViewEventHandler::OnGLFWMouseMoveCallBack);
    glfwSetCharCallback(_mainWindow, EGLViewEventHandler::OnGLFWCharCallback);
    glfwSetKeyCallback(_mainWindow, EGLViewEventHandler::OnGLFWKeyCallback);

然后：

void EGLViewEventHandler::OnGLFWMouseCallBack(GLFWwindow* window, int button, int action, int modify)
{
    EGLView* eglView = EGLView::getInstance();
    if(nullptr == eglView) return;
    if(GLFW_MOUSE_BUTTON_LEFT == button)
    {
        if(GLFW_PRESS == action)
        {
            s_captured = true;
            if (eglView->getViewPortRect().equals(Rect::ZERO) || eglView->getViewPortRect().containsPoint(Point(s_mouseX,s_mouseY)))
            {
                int id = 0;
                eglView->handleTouchesBegin(1, &id, &s_mouseX, &s_mouseY);//注意
            }
        }
        else if(GLFW_RELEASE == action)
        {
            s_captured = false;
            if (eglView->getViewPortRect().equals(Rect::ZERO) || eglView->getViewPortRect().containsPoint(Point(s_mouseX,s_mouseY)))
            {
                int id = 0;
                eglView->handleTouchesEnd(1, &id, &s_mouseX, &s_mouseY);
            }
        }
    }
}

void EGLViewProtocol::handleTouchesBegin(int num, int ids[], float xs[], float ys[])
{
    int id = 0;
    float x = 0.0f;
    float y = 0.0f;
    int nUnusedIndex = 0;
    EventTouch touchEvent;
    
    for (int i = 0; i < num; ++i)
    {
        id = ids[i];
        x = xs[i];
        y = ys[i];

        auto iter = g_touchIdReorderMap.find(id);
        nUnusedIndex = 0;

        // it is a new touch
        if (iter == g_touchIdReorderMap.end())
        {
            nUnusedIndex = getUnUsedIndex();

            // The touches is more than MAX_TOUCHES ?
            if (nUnusedIndex == -1) {
                CCLOG("The touches is more than MAX_TOUCHES, nUnusedIndex = %d", nUnusedIndex);
                continue;
            }

            Touch* touch = g_touches[nUnusedIndex] = new Touch();
			touch->setTouchInfo(nUnusedIndex, (x - _viewPortRect.origin.x) / _scaleX, 
                                     (y - _viewPortRect.origin.y) / _scaleY);
            
            CCLOGINFO("x = %f y = %f", pTouch->getLocationInView().x, pTouch->getLocationInView().y);
            
            g_touchIdReorderMap.insert(std::make_pair(id, nUnusedIndex));
            touchEvent._touches.push_back(touch);
        }
    }

    if (touchEvent._touches.size() == 0)
    {
        CCLOG("touchesBegan: size = 0");
        return;
    }
    
    touchEvent._eventCode = EventTouch::EventCode::BEGAN;
    EventDispatcher::getInstance()->dispatchEvent(&touchEvent);//在这里会分发并回调touch的相关事件和回调函数
}

ok，想要了解细节，还是看源码吧，很清晰。因为木有设置啥多线程调用。