指定背景的淡入淡出

天云上人

创建步骤：
1、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
7 E* b* ^* B" F( b' t6 j函数设置调色板，改变显示结果。
2 E0 ?, Z. w' n2、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
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
2 H6 E# u7 p  N改位图调色板，显示位图改变显示结果
& R6 ~; M( r) q9 p返回：位图的淡入淡出
# R6 S4 u2 O3 ?8 u( c- f$ N6 g//参数说明：
//hDIB -位图句柄
5 |' ?' t% a: L2 [# K//color -指定背景色
' Y/ C0 t; q8 N6 k//xDest -显示位图的左上角x坐标
//yDest -显示位图的左上角y坐标
//nLoops -循环次数
- u2 q" ?& v3 ^& X* u, @- l9 V" m//nDelay -每次循环中的延时
//nFlag -淡入淡出标志 1--淡入 其它--淡出
  L/ M# q0 y5 T& W$ qvoid FadeInORFadeOut( CDC *pDC, HANDLE hDIB, COLORREF color, int xDest, int yDest,
int nLoops, int nDelay ,int nFlag)
int i,j;
' X3 X9 L+ p: w+ IHPALETTE hPal;
/ x0 F, h$ N( L6 W& f: tPALETTEENTRY pAnimate[256];
PALETTEENTRY pOriginal[256];
3 e, L# s2 K5 Z0 \% w2 c: RCPalette pal;
# u% q2 z" R( m0 p( X// 创建236色调色板
　
; `! D- c1 g" z4 W( u- vBITMAPINFO &bmInfo = *(LPBITMAPINFO)hDIB ;
　
int nColors = bmInfo.bmiHeader.biClrUsed ? bmInfo.bmiHeader.biClrUsed :
1 << bmInfo.bmiHeader.biBitCount;
6 w9 [4 i( T7 Q2 H) v8 c+ Z- v8 eint nWidth = bmInfo.bmiHeader.biWidth;
. q  D3 m0 \: [9 b; F2 ]int nHeight = bmInfo.bmiHeader.biHeight;
. O: L" G# M8 I) KLPVOID lpDIBBits = (LPVOID)(bmInfo.bmiColors + nColors);
int clrRValue = GetRValue(color);
* {! o& H4 M; g! ^int clrGValue = GetGValue(color);
8 y3 I9 m3 [* B& Dint clrBValue = GetBValue(color);
if( pDC->GetDeviceCaps(RASTERCAPS) & RC_PALETTE && nColors <= 256 )
if (!(hPal = Create236Palette(hDIB)))
0 w! N0 p1 _* i4 R7 r8 Jreturn;
2 k8 J, d6 Z7 o6 D1 npal.Attach( hPal );
// 得到调色板初始值
$ Y2 K# s, b( ^1 q- _, dGetPaletteEntries(hPal, 0, nColors, (LPPALETTEENTRY)&pOriginal);
// 设定动态调色板初始值为指定色
0 p; B3 \; U7 e2 l. v7 fif(nFlag==1)
for (j = 0; j < nColors; j++)
( h( f& M0 ~- k# }6 DpAnimate[j].peRed = clrRValue;
: _" Y( K/ K* {* q- K0 BpAnimate[j].peGreen = clrGValue;
: @; u- z- V+ f# CpAnimate[j].peBlue = clrBValue;
+ d. m) p, r+ H! T) X. xpAnimate[j].peFlags = PC_RESERVED;
else
: i: E: @: T% z' e( y1 QGetPaletteEntries(hPal, 0, nColors, (LPPALETTEENTRY)&pAnimate);
% V# b( V1 m6 ^) MCPalette *pOldPalette = pDC->SelectPalette(&pal, FALSE);
9 Z8 L# u* m+ B- f# hpDC->RealizePalette();
CDC memDC;
& A6 {" M1 N8 C  dmemDC.CreateCompatibleDC( pDC );
CBitmap bmp;
1 p4 n" m% g* k; _* sbmp.CreateCompatibleBitmap( pDC, nWidth, nHeight );
! S& b) Y7 v7 k( xCBitmap *pOldBitmap = memDC.SelectObject( &bmp );
, ^( w# ]6 P/ i" x! e0 ^" C7 iCPalette *pOldMemPalette = memDC.SelectPalette(&pal, FALSE);
  x( Y3 t( ]7 }% {8 p3 s* k, fmemDC.RealizePalette();
$ m: _1 `' C, b- X& j$ L::SetDIBitsToDevice(memDC.m_hDC,0,0,nWidth,nHeight,0,0,0,nHeight,lpDIBBits,(LPBITMAPINFO)hDIB,DIB_RGB_COLORS);
( {' d5 n3 p8 V8 j1 MAnimatePalette(hPal, 0, nColors, (LPPALETTEENTRY)&pAnimate);
4 E5 U3 s/ h% \. L; o* R$ _+ ypDC->BitBlt(xDest, yDest, nWidth, nHeight, &memDC,0,0,SRCCOPY );
// 淡入淡出
! N% [& A& O: H2 k1 v% Efor( i=1; i <= nLoops; i++ )
for (j = 0; j < nColors; j++)
$ q" ]# ~* m6 f- c+ M2 Kif(nFlag==1)
pAnimate[j].peRed = clrRValue - ((clrRValue-pOriginal[j].peRed)*i)/nLoops;
pAnimate[j].peGreen = clrGValue - ((clrGValue-pOriginal[j].peGreen)*i)/nLoops;
pAnimate[j].peBlue = clrBValue - ((clrBValue-pOriginal[j].peBlue)*i)/nLoops;
* \; l' F0 o% X. k' h' telse
4 s1 {) j$ }7 g+ V2 J4 FpAnimate[j].peRed = pOriginal[j].peRed - ((pOriginal[j].peRed - clrRValue)*i)/nLoops;
pAnimate[j].peGreen = pOriginal[j].peGreen - ((pOriginal[j].peGreen - clrGValue)*i)/nLoops;
( D4 X4 s5 B# \pAnimate[j].peBlue = pOriginal[j].peBlue - ((pOriginal[j].peBlue - clrBValue)*i)/nLoops;
+ x* D: X+ O3 R2 ?pal.AnimatePalette(0, nColors, (LPPALETTEENTRY)&pAnimate);
// Delay...
; `7 E' C6 @4 @3 `1 D1 L* gSleep(nDelay);
, v4 P2 {) U- g+ fmemDC.SelectPalette(pOldMemPalette, FALSE);
" Y7 p1 ~$ V' d  |* O. TmemDC.SelectObject( pOldBitmap );
( ?: w6 X' l5 e' HpDC->SelectPalette(pOldPalette, FALSE);
else if( (pDC->GetDeviceCaps(RASTERCAPS) & RC_PALETTE) == 0 && nColors <= 256 )
for( int i=0; i < nColors; i++)
" n2 S* e* @3 x" p! B5 u1 jpOriginal.peRed = bmInfo.bmiColors.rgbRed ;
pOriginal.peGreen = bmInfo.bmiColors.rgbGreen;
# B9 e0 \* Q$ r5 Q$ ypOriginal.peBlue = bmInfo.bmiColors.rgbBlue ;
if(nFlag==1)
: H4 W& ], k( X+ H, O2 EbmInfo.bmiColors.rgbRed = clrRValue;
+ \1 t9 ?8 Y) m% cbmInfo.bmiColors.rgbGreen = clrGValue;
bmInfo.bmiColors.rgbBlue = clrBValue;
. P9 R8 Q* C! ~- {::SetDIBitsToDevice(pDC->m_hDC,0,0,nWidth,nHeight,0,0,0,nHeight,lpDIBBits,(LPBITMAPINFO)hDIB,DIB_RGB_COLORS);
// 淡入淡出
for( i=1; i <= nLoops; i++ )
for (j = 0; j < nColors; j++)
, j  N; C- w/ O$ t+ x* y2 B" ~if(nFlag==1)
3 h8 ]! U$ u  H# h1 l' I1 O- mbmInfo.bmiColors[j].rgbRed = clrRValue - ((clrRValue-pOriginal[j].peRed)*i)/nLoops;
bmInfo.bmiColors[j].rgbGreen = clrGValue - ((clrGValue-pOriginal[j].peGreen)*i)/nLoops;
bmInfo.bmiColors[j].rgbBlue = clrBValue - ((clrBValue-pOriginal[j].peBlue)*i)/nLoops;
, D8 B* }2 X; `+ ~else
" W* W8 i; S1 m' R' L/ D- ]+ m) ZbmInfo.bmiColors[j].rgbRed = pOriginal[j].peRed - ((pOriginal[j].peRed-clrRValue)*i)/nLoops;
bmInfo.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;
8 r; c7 R9 A4 }2 m- b% e7 s3 Y2 H- ~' }# h::SetDIBitsToDevice(pDC->m_hDC,0,0,nWidth,nHeight,0,0,0,nHeight,lpDIBBits,(LPBITMAPINFO)hDIB,DIB_RGB_COLORS);
" g. ?. G) X% G3 T// Delay...
Sleep(nDelay);