指定背景的淡入淡出

天云上人

创建步骤：
4 W8 }3 }! ?) I7 l+ U) a1、如果系统支持调色板，创建动态调色板pAnimate与初始调色板pOriginal。
从位图中获取初始调色板，若为淡入将背景色赋予动态调色板。利用前面所
提到的公式，根据淡入淡出标志，在循环中更改动态调色板，用AnimatePalette
8 d4 H  J  s# o# P. }函数设置调色板，改变显示结果。
2、如果系统不支持调色板，保存位图调色板到初始调色板，若为淡入将背景
) v% G; c: E1 D/ b$ z色赋予位图调色板，利用前面所提到的公式，根据淡入淡出标志，在循环中更
0 w9 `+ c5 g& Z5 M* Y# U  E% g改位图调色板，显示位图改变显示结果
7 R& \# I$ Y) b) X% `6 y& F- O返回：位图的淡入淡出
+ _7 G* n2 E5 K5 Z* x//参数说明：
% `+ `& ~# e: F0 b8 |) l$ c//hDIB -位图句柄
" c: z, G: t* d) M//color -指定背景色
/ A  `, F6 |: G1 C/ @6 L//xDest -显示位图的左上角x坐标
0 I. J: p2 A. l( t9 z//yDest -显示位图的左上角y坐标
//nLoops -循环次数
//nDelay -每次循环中的延时
//nFlag -淡入淡出标志 1--淡入 其它--淡出
void FadeInORFadeOut( CDC *pDC, HANDLE hDIB, COLORREF color, int xDest, int yDest,
int nLoops, int nDelay ,int nFlag)
' K2 a( U3 M3 B5 v* Bint i,j;
HPALETTE hPal;
8 f$ O, Z. i/ IPALETTEENTRY pAnimate[256];
- R+ U7 A! Q% N* t- S7 d$ U$ h% zPALETTEENTRY pOriginal[256];
( |5 H7 [6 ]4 s- oCPalette pal;
// 创建236色调色板
! k, u0 q( [/ i8 e; y3 B( _　
4 |. q5 s$ Q9 Y  M0 B# lBITMAPINFO &bmInfo = *(LPBITMAPINFO)hDIB ;
. u9 ]- w8 D" z; f. k0 l. S　
* f- C& Q& D1 l! K% R' qint nColors = bmInfo.bmiHeader.biClrUsed ? bmInfo.bmiHeader.biClrUsed :
+ T" b4 X& m& ^; A( p1 << bmInfo.bmiHeader.biBitCount;
0 I. u$ Y( P+ O- O# Kint nWidth = bmInfo.bmiHeader.biWidth;
2 N# l- @$ c8 K3 {int nHeight = bmInfo.bmiHeader.biHeight;
2 b. I% ]1 j+ w$ _LPVOID lpDIBBits = (LPVOID)(bmInfo.bmiColors + nColors);
0 P( x( L  e8 i, G1 V2 mint clrRValue = GetRValue(color);
) ?5 s$ n3 l+ F( k7 X* j4 G3 i/ fint clrGValue = GetGValue(color);
$ c  P! Z/ t7 b! G3 _$ k6 Mint clrBValue = GetBValue(color);
if( pDC->GetDeviceCaps(RASTERCAPS) & RC_PALETTE && nColors <= 256 )
) P1 R, r9 Y$ C! y* W1 Wif (!(hPal = Create236Palette(hDIB)))
return;
( h; \* e" ^: P, Y/ h  Npal.Attach( hPal );
// 得到调色板初始值
  _+ i% b0 J# w; y( XGetPaletteEntries(hPal, 0, nColors, (LPPALETTEENTRY)&pOriginal);
// 设定动态调色板初始值为指定色
" T. C$ x# [5 Dif(nFlag==1)
( i6 j: j% k$ {7 pfor (j = 0; j < nColors; j++)
pAnimate[j].peRed = clrRValue;
pAnimate[j].peGreen = clrGValue;
. y/ @: @+ r" `$ Y3 ApAnimate[j].peBlue = clrBValue;
, h9 ~# b/ P) u6 W& i1 d9 X+ ipAnimate[j].peFlags = PC_RESERVED;
else
6 {1 o. n0 \; X3 @' S$ gGetPaletteEntries(hPal, 0, nColors, (LPPALETTEENTRY)&pAnimate);
CPalette *pOldPalette = pDC->SelectPalette(&pal, FALSE);
& P/ j* L; T. H# Y% K2 F) HpDC->RealizePalette();
! _1 O5 I/ H* r, f' hCDC memDC;
0 l) V' f# T# q/ q' P8 r3 ImemDC.CreateCompatibleDC( pDC );
CBitmap bmp;
/ M" W5 I' H- t$ A# i& P$ Hbmp.CreateCompatibleBitmap( pDC, nWidth, nHeight );
7 u% E+ W: \2 n' d- N' p& @CBitmap *pOldBitmap = memDC.SelectObject( &bmp );
, E8 ~7 a  k( B" {CPalette *pOldMemPalette = memDC.SelectPalette(&pal, FALSE);
memDC.RealizePalette();
::SetDIBitsToDevice(memDC.m_hDC,0,0,nWidth,nHeight,0,0,0,nHeight,lpDIBBits,(LPBITMAPINFO)hDIB,DIB_RGB_COLORS);
- @/ C) o0 W! I7 AAnimatePalette(hPal, 0, nColors, (LPPALETTEENTRY)&pAnimate);
; x$ p% _1 V' E( R  YpDC->BitBlt(xDest, yDest, nWidth, nHeight, &memDC,0,0,SRCCOPY );
8 l/ a- y% e! X; p+ ?4 |1 T// 淡入淡出
for( i=1; i <= nLoops; i++ )
' s' S8 Q  i  o& Qfor (j = 0; j < nColors; j++)
if(nFlag==1)
/ y) _. d) v# z) z. H; vpAnimate[j].peRed = clrRValue - ((clrRValue-pOriginal[j].peRed)*i)/nLoops;
7 k" S+ p# N$ c% t6 J  X3 l9 gpAnimate[j].peGreen = clrGValue - ((clrGValue-pOriginal[j].peGreen)*i)/nLoops;
# ^5 G* {. r5 K6 N: w# ]' BpAnimate[j].peBlue = clrBValue - ((clrBValue-pOriginal[j].peBlue)*i)/nLoops;
else
. ^& |" y5 N: n+ CpAnimate[j].peRed = pOriginal[j].peRed - ((pOriginal[j].peRed - clrRValue)*i)/nLoops;
+ g& ]$ I" x0 a( p4 }3 [pAnimate[j].peGreen = pOriginal[j].peGreen - ((pOriginal[j].peGreen - clrGValue)*i)/nLoops;
* Q9 ~9 x* S: ]) d, Y+ l( jpAnimate[j].peBlue = pOriginal[j].peBlue - ((pOriginal[j].peBlue - clrBValue)*i)/nLoops;
& f7 U% W& z. n1 m8 bpal.AnimatePalette(0, nColors, (LPPALETTEENTRY)&pAnimate);
/ n& @9 l* k8 p4 f! D" L; t// Delay...
Sleep(nDelay);
. p+ [/ }( o5 T. ~memDC.SelectPalette(pOldMemPalette, FALSE);
, @4 O6 p1 [0 u. q  P/ ymemDC.SelectObject( pOldBitmap );
pDC->SelectPalette(pOldPalette, FALSE);
else if( (pDC->GetDeviceCaps(RASTERCAPS) & RC_PALETTE) == 0 && nColors <= 256 )
for( int i=0; i < nColors; i++)
pOriginal.peRed = bmInfo.bmiColors.rgbRed ;
! @( y; Q* {& A" KpOriginal.peGreen = bmInfo.bmiColors.rgbGreen;
pOriginal.peBlue = bmInfo.bmiColors.rgbBlue ;
if(nFlag==1)
bmInfo.bmiColors.rgbRed = clrRValue;
bmInfo.bmiColors.rgbGreen = clrGValue;
# `; I8 y& s, G3 F2 ibmInfo.bmiColors.rgbBlue = clrBValue;
::SetDIBitsToDevice(pDC->m_hDC,0,0,nWidth,nHeight,0,0,0,nHeight,lpDIBBits,(LPBITMAPINFO)hDIB,DIB_RGB_COLORS);
0 a: b. e' c+ J  D, x// 淡入淡出
for( i=1; i <= nLoops; i++ )
' c+ G; d5 \2 n, j) \  ?/ `for (j = 0; j < nColors; j++)
9 f1 M: h* R, uif(nFlag==1)
bmInfo.bmiColors[j].rgbRed = clrRValue - ((clrRValue-pOriginal[j].peRed)*i)/nLoops;
: \( U$ E; I; e+ l- A. `' ybmInfo.bmiColors[j].rgbGreen = clrGValue - ((clrGValue-pOriginal[j].peGreen)*i)/nLoops;
6 M+ T2 A. m: K7 A) h9 j$ p  [+ W0 lbmInfo.bmiColors[j].rgbBlue = clrBValue - ((clrBValue-pOriginal[j].peBlue)*i)/nLoops;
else
- y, _' J/ B0 abmInfo.bmiColors[j].rgbRed = pOriginal[j].peRed - ((pOriginal[j].peRed-clrRValue)*i)/nLoops;
$ C1 C0 {3 p8 ?  RbmInfo.bmiColors[j].rgbGreen = pOriginal[j].peGreen - ((pOriginal[j].peGreen-clrGValue)*i)/nLoops;
bmInfo.bmiColors[j].rgbBlue = pOriginal[j].peBlue - ((pOriginal[j].peBlue-clrBValue)*i)/nLoops;
::SetDIBitsToDevice(pDC->m_hDC,0,0,nWidth,nHeight,0,0,0,nHeight,lpDIBBits,(LPBITMAPINFO)hDIB,DIB_RGB_COLORS);
( o* g. E2 L; R4 M% D, c5 U$ c// Delay...
# S, t9 M( y% ^# X# Y" `Sleep(nDelay);