BitmapView.h

#ifndef __VIEW_H__
#define __VIEW_H__

#pragma once

#include <atlscrl.h>
#include <atlcrack.h>
#include <atltypes.h>

#include "Image.h"

class CBitmapView : public CZoomScrollWindowImpl<CBitmapView>
{
public:
    friend CZoomScrollImpl<CBitmapView>;
    friend CScrollImpl<CBitmapView>;
    DECLARE_WND_CLASS_EX(NULL, CS_HREDRAW | CS_VREDRAW, -1)

    CBitmapView();

    BOOL PreTranslateMessage(MSG* pMsg);
    void ClearBitmap();
    void SetBitmap(Image image, bool bResetOffset = true);
    const Image& GetImage() const { return m_image; }
    void SetBackground(HBRUSH hBackground);
    const CBrush& GetBackground() const { return m_hBackground; }

    void SetFrame(UINT nFrame);
    void SetFlipRotate(WICBitmapTransformOptions FlipRotate);
    HBITMAP CreateBitmap(HDC hDC) const { return m_image.ConvertToBitmap(hDC, m_hBackground); }

    void ZoomToFit();

    void SaveImage(LPCTSTR lpFilename) const { m_image.Save(lpFilename); }

private:
    void DoPaint(CDCHandle dc) const;

    bool AdjustScrollOffset(int& x, int& y);
    void InvalidateCursor();
    void UpdateScrollSize(bool bResetOffset);

    BEGIN_MSG_MAP(CBitmapView)
        MSG_WM_ERASEBKGND(OnEraseBackground)
        MSG_WM_KEYDOWN(OnKeyDown)
        MSG_WM_KEYUP(OnKeyUp)
        MSG_WM_LBUTTONDOWN(OnLButtonDown)
        MSG_WM_LBUTTONUP(OnLButtonUp)
        MSG_WM_MOUSEMOVE(OnMouseMove)
        MSG_WM_CAPTURECHANGED(OnCaptureChanged)
        MSG_WM_SETCURSOR(OnSetCursor)

        CHAIN_MSG_MAP(CZoomScrollWindowImpl<CBitmapView>);
    END_MSG_MAP()

private:
    Image m_image;
    CBrush m_hBackground;
    CPoint m_pointDrag;
    bool m_bPanning;

    BOOL OnEraseBackground(CDCHandle dc);
    void OnKeyDown(UINT nChar, UINT nRepCnt, UINT nFlags);
    void OnKeyUp(UINT nChar, UINT nRepCnt, UINT nFlags);
    void OnLButtonDown(UINT nFlags, CPoint point);
    void OnLButtonUp(UINT nFlags, CPoint point);
    void OnMouseMove(UINT nFlags, CPoint point);
    void OnCaptureChanged(CWindow wnd);
    BOOL OnSetCursor(CWindow wnd, UINT nHitTest, UINT message);
};

#endif // __VIEW_H__