使用Ogre3D在Windows中关注MouseOver

Question

我有一个使用Ogre3D创建多个渲染窗口的应用程序，并且我正在使用发布的解决方案here来支持对这些窗口的非独占鼠标输入。然而，我发现我必须在渲染窗口重新获得焦点之前物理地单击它，而我真的希望渲染窗口在鼠标悬停事件上获得焦点。是否可以在Ogre3D/OIS中捕获未聚焦的渲染窗口上的鼠标悬停事件，然后设置渲染窗口的焦点？

Answer 1

为了在Windows中使用Ogre3D支持这种功能，我必须实现一个单例对象，该对象保存所有实例化显示的集合。

class InputProcessor
{
    /// @name Types
    /// @{
public:
    /// @}

    /// @name InputProcessor implementation
    /// @{
public:
    void addDisplay(Display* _pDisplay);

    bool processMouseMoved(int _x, int _y, int _z, int _keyModifier);
    bool processMousePressed(int _keyModifier, int _id);
    bool processMouseReleased(int _keyModifier, int _id);

    static InputProcessor& getSingleton();
    /// @}

    /// @name 'Structors
    /// @{
private:
     InputProcessor();
    ~InputProcessor();
    /// @}

    /// @name Member Variables
    /// @{
private:
    typedef std::set<Display*>     Displays_type;
    Displays_type                  m_displays;
    /// @}

};  // class InputProcessor

然后，在我的UIFrameListener (它派生自Ogre3D的ExampleFrameListener)中，我将鼠标窗口坐标转换为全局屏幕坐标。如果鼠标恰好位于窗口区域之外，则将鼠标的相对移动应用于最后记录的鼠标位置；否则，仅应用窗口内的绝对鼠标位置：

bool
UIFrameListener::mouseMoved(const OIS::MouseEvent& e)
{
    int keyModifierState = GetKeyModifierState();
    int windowLeft = m_display.getLeft();
    int windowTop = m_display.getTop();
    int windowWidth = m_display.m_pWindow->getWidth();
    int windowHeight = m_display.m_pWindow->getHeight();

    if (e.state.X.abs != 0 && e.state.X.abs != windowWidth)
    {
        m_lastX = e.state.X.abs;
    }
    else
    {
        m_lastX += e.state.X.rel;
    }
    int x = windowLeft + (m_display.m_width * m_lastX) / windowWidth;

    if (e.state.Y.abs != 0 && e.state.Y.abs != windowHeight)
    {
        m_lastY = e.state.Y.abs;
    }
    else
    {
        m_lastY += e.state.Y.rel;
    }
    int y = windowTop + (m_display.m_height * m_lastY) / windowHeight;

    int z = 0;
    if (e.state.Z.rel != 0)
    {
        z = e.state.Z.rel / -120;
    }

    return InputProcessor::getSingleton().processMouseMoved(x, y, z, keyModifierState);
}

在InputProcessor::processMouseMoved()中，我确定鼠标光标在哪个窗口中(如果有)，然后适当地设置焦点，即

bool
InputProcessor::processMouseMoved(int _x,
                                  int _y,
                                  int _z,
                                  int _keyModifier)
{
    bool found = false;

    Displays_type::iterator iter = m_displays.begin();
    while (iter != m_displays.end() && !found)
    {
        int left = (*iter)->getLeft();
        int top = (*iter)->getTop();
        int width = (*iter)->m_pWindow->getWidth();
        int height = (*iter)->m_pWindow->getHeight();

        if (left <= _x && left + width  > _x &&
            top  <= _y && top  + height > _y)
        {
            found = true;
        }
        else
        {
            iter++;
        }
    }

    if (iter != m_displays.end())
    {
        int left = (*iter)->getLeft();
        int top = (*iter)->getTop();

        (*iter)->m_pContext->ProcessMouseMove(
            _x - left, _y - top, _keyModifier
        );

        (*iter)->m_pContext->ProcessMouseWheel(_z, _keyModifier);

        if (!(*iter)->hasFocus())
        {
            (*iter)->setFocus(true);
        }
    }

    return true;
}

在Display的实现中，我有一个Display::setFocus()方法，它将焦点设置在适当的窗口上：

void
Display::setFocus(bool _hasFocus)
{
    if (m_handle != NULL && _hasFocus)
    {
        SetFocus(m_handle);
    }
}