Mouse Gestures for Internet Explorer

///////////////////////////////////////////////////////////////
//
// TrailWindow.h
//
// Created: 28/06/2005
// Copyright (c) 2005 Ralph Hare (ralph.hare@ysgyfarnog.co.uk)
// All rights reserved.
//
// The code and information is provided "as-is" without
// warranty of any kind, either expressed or implied.
//
///////////////////////////////////////////////////////////////

#ifndef __TRAILWINDOW_H_4AC74882_21E3_469D_A937_32CAD7268D0C_
#define __TRAILWINDOW_H_4AC74882_21E3_469D_A937_32CAD7268D0C_

#include "MouseTrail.h"
#include "CriticalSection.h"
#include <atlmisc.h>

/**
 * @brief Concrete implementation of the MouseTrail interface
 *
 * The TrailWindow creates a transparent window that covers the whole
 * screen. When the user performs a mouse gesture, the gesture path
 * is fed to TrailWindow and drawn over the active window(s).
 *
 * The mouse trail is drawn to a memory DC before being blitted to
 * the windows DC.
 **/
class TrailWindow : 
    public CWindowImpl< TrailWindow >,
    public MouseTrail
{
public:
    TrailWindow( COLORREF clr, long thickness, BYTE transparency, long fadeSpeed );
    ~TrailWindow();

BEGIN_MSG_MAP( ToolTip )
    MESSAGE_HANDLER( WM_DISPLAYCHANGE, OnDisplayChange )
    MESSAGE_HANDLER( WM_TIMER, OnTimer )
END_MSG_MAP()

public:
    static CWndClassInfo & GetWndClassInfo();

    void UpdateSettings( COLORREF clr, long thickness, BYTE transparency, long fadeSpeed );

private:
    LRESULT OnDisplayChange( UINT, WPARAM, LPARAM, BOOL & );
    LRESULT OnTimer( UINT, WPARAM, LPARAM, BOOL & );
    
// MouseTrail
private:
    virtual void Begin( HWND hWnd );
    virtual void End();
    virtual void Update( const Path &path );
    virtual void Show();
    virtual void Hide();

private:
    void SetTransparency( BYTE transparency );
    void DrawTrail( HDC hDC );
    void UpdateBitmap();

private:
    WTL::CSize              m_offset;           /// < the co-ordinates of the top-left of the window
                                                ///   that the path is relative to
    WTL::CPoint             m_lastPoint;        /// < the last point on the path we drew
    std::vector< POINT >    m_path;             /// < the adjusted path

    WTL::CDC        m_memDC;                    /// < the memory DC
    WTL::CBitmap    m_bitmap;                   /// < a bitmap compatible with the current DC, large
                                                ///   enough to cover the entire screen
    WTL::CPen       m_pen;                      /// < the pen to draw the trail
    WTL::CPen       m_penEnd;                   /// < a pen for drawing the end marker
    WTL::CBrush     m_brush;                    /// < a brush to draw the beginning & end markers
    WTL::CRect      m_rcWnd;                    /// < the size of the TrailWindow
    WTL::CRect      m_rcExtents;                /// < the bounding rect for the path

    long    m_penWidth;
    BYTE    m_transparency;
    int     m_fadeIncrement;                    /// < the increment in transparency to be used
                                                ///   when fading the window. The bigger the number,
                                                ///   the faster the fade
    double  m_sensitivity;                      /// < the number of pixels the mouse has to move
                                                ///   before the path is updated

    CriticalSection     m_csShow;
};

#endif // __TRAILWINDOW_H_4AC74882_21E3_469D_A937_32CAD7268D0C_