windows-nt/Source/XPSP1/NT/windows/richedit/re41/_osdc.h
2020-09-26 16:20:57 +08:00

125 lines
3.3 KiB
C++

/* @doc INTERNAL
*
* @module _OSDC.H Off Screen DC class |
*
* Define class for off screen DC
*
* Original Author: <nl>
* Ricksa
*
* History: <nl>
* 1/11/96 ricksa Created
*
* Copyright (c) 1996-1998, Microsoft Corporation. All rights reserved.
*/
#ifndef __OSDC_H__
#define __OSDC_H__
/*
* COffscreenDC
*
* @class The COffscreenDC is a helper that creates, fills and destroys
* an off screen DC and its bitmaps.
*
*/
class COffscreenDC
{
//@access Public Methods
public:
//@cmember Constructor - create null object.
COffscreenDC() {_hdc = NULL;}
//@cmember Destructor - clean up allocated
// resources if any.
~COffscreenDC() {FreeData();}
//@cmember Initialize data based on input DC
HDC Init(HDC hdc, LONG xWidth, LONG yHeight, COLORREF crBackground);
//@cmember Get DC for offscreen rendering
HDC GetDC() {return _hdc;}
void GetDimensions(LONG *pdxp, LONG *pdyp);//@cmember the dimensions of the bitmap
//@cmember Fill bitmap associated with off
// screen rendering with background color.
void FillBitmap(LONG dxp, LONG dyp);
//@cmember Render off screen bitmap to hdc
void RenderBitMap(HDC hdc, LONG xLeft, LONG yTop, LONG xWidth, LONG yHeight);
//@cmember Get a copy of a bitmap from hdc
BOOL Get(HDC hdc, LONG xLeft, LONG yTop, LONG xWidth, LONG yHeight);
//@cmember Reallocate bitmap for render
BOOL Realloc(LONG xWidth, LONG yHeight);
//@cmember Select in a palette
void SelectPalette(HPALETTE hpa);
//@access Private Methods
private:
//@cmember Free all data associated with object
void FreeData();
//@access Private Data
private:
HDC _hdc; //@cmember HDC for off screen DC
HBITMAP _hbmpOld; //@cmember bitmap when DC created
HBITMAP _hbmp; //@cmember compatible bitmap for render
HPALETTE _hpalOld; //@cmember palette used by DC
};
/*
* COffscreenDC::FillBitmap (xWidth, yHeight)
*
* @mfunc
* Fill bitmap
*/
inline void COffscreenDC::FillBitmap(
LONG dxp, //@parm Width to fill with background color
LONG dyp) //@parm height to fill with background color
{
// Erase background
RECT rcClient;
rcClient.top = rcClient.left = 0;
rcClient.right = dxp;
rcClient.bottom = dyp;
ExtTextOut(_hdc, 0, 0, ETO_OPAQUE, &rcClient, NULL, 0, NULL);
}
/*
* COffscreenDC::RenderBitMap(hdc, xLeft, yTop, xWidth, yHeight)
*
* @mfunc
* Render bitmap to input DC
*/
inline void COffscreenDC::RenderBitMap(
HDC hdc, //@parm HDC to render to
LONG xLeft, //@parm left position to start render
LONG yTop, //@parm top top position to start render
LONG xWidth, //@parm width to render
LONG yHeight) //@parm height to render
{
BitBlt(hdc, xLeft, yTop, xWidth, yHeight, _hdc, 0, 0, SRCCOPY);
}
/*
* COffscreenDC::Get(hdc, xLeft, yTop, xWidth, yHeight)
*
* @mfunc
* Get a copy of a bitmap from another DC
*
* @rdesc
* TRUE - succeeded
* FALSE - Failed
*/
inline BOOL COffscreenDC::Get(
HDC hdc, //@parm HDC to copy from
LONG xLeft, //@parm left position of source bitmap
LONG yTop, //@parm top top position of source bitmap
LONG xWidth, //@parm width of bitmap
LONG yHeight) //@parm height to bitmap
{
return BitBlt(_hdc, 0, 0, xWidth, yHeight, hdc, xLeft, yTop, SRCCOPY);
}
#endif __OSDC_H__