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
8 r6 d6 @( k! M, b0 H' a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 A5 V: g  U7 Y* f7 E8 g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
0 V  X+ M1 U8 h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
. ?5 Y3 E1 ?8 Y+ Y0 U0 Z* u改位图调色板，显示位图改变显示结果
返回：位图的淡入淡出
//参数说明：
//hDIB -位图句柄
# [) T# m; o  H! T1 Z% v+ a//color -指定背景色
: E  f) r. O' ~% l" f//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
' }* u' V5 r8 X0 L: O4 Q4 s5 \//nDelay -每次循环中的延时
4 u2 P0 f( m4 p, v# _% U$ F. w) s! N! ^//nFlag -淡入淡出标志 1--淡入 其它--淡出
4 |0 I4 C4 i0 Z0 ~5 M* F4 jvoid FadeInORFadeOut( CDC *pDC, HANDLE hDIB, COLORREF color, int xDest, int yDest,
' [" A" [  p+ F! `int nLoops, int nDelay ,int nFlag)
' ]& P. z3 H1 P# Y4 Gint i,j;
HPALETTE hPal;
; a* S1 O% Q; S0 D3 HPALETTEENTRY pAnimate[256];
2 b6 d7 e$ ~/ N7 [  S5 |  x3 n: A; TPALETTEENTRY pOriginal[256];
CPalette pal;
+ ~! }+ C+ q' g/ C* Q! B- j  M0 S// 创建236色调色板
2 K+ P: e- k1 J& p　
1 D. Z2 o( e7 F; _7 f6 fBITMAPINFO &bmInfo = *(LPBITMAPINFO)hDIB ;
' h7 t% x# C. E  |* }/ W　
int nColors = bmInfo.bmiHeader.biClrUsed ? bmInfo.bmiHeader.biClrUsed :
$ @# L7 A4 p: z) {1 << bmInfo.bmiHeader.biBitCount;
8 T( h/ p5 q- r% F+ ^- ?4 ]' Q) zint nWidth = bmInfo.bmiHeader.biWidth;
int nHeight = bmInfo.bmiHeader.biHeight;
; L0 i- k( R  x0 p, z+ S6 q9 ALPVOID lpDIBBits = (LPVOID)(bmInfo.bmiColors + nColors);
int clrRValue = GetRValue(color);
5 w6 }& q' A0 n& `5 Iint clrGValue = GetGValue(color);
1 z" C) ~  S4 _, ~! P. }4 s; Pint clrBValue = GetBValue(color);
  i$ }* A$ q( A! x8 J" _! Fif( pDC->GetDeviceCaps(RASTERCAPS) & RC_PALETTE && nColors <= 256 )
( d  E" D+ v" G0 L4 I8 i8 [* I9 oif (!(hPal = Create236Palette(hDIB)))
, V5 C, L; X" L" f; Q+ A( }return;
pal.Attach( hPal );
7 G4 \6 G8 S  z3 p// 得到调色板初始值
) V: p) G4 J2 N" @GetPaletteEntries(hPal, 0, nColors, (LPPALETTEENTRY)&pOriginal);
$ G, n# K# G" P5 n8 f. P// 设定动态调色板初始值为指定色
/ w) j- c2 u: a+ X% @2 Rif(nFlag==1)
, U4 V. H' U  V! afor (j = 0; j < nColors; j++)
pAnimate[j].peRed = clrRValue;
1 [3 P3 E( C, UpAnimate[j].peGreen = clrGValue;
: C* {0 A/ S1 }7 N7 h! r" \pAnimate[j].peBlue = clrBValue;
- E4 }; s5 d2 u0 E5 ppAnimate[j].peFlags = PC_RESERVED;
else
5 _7 ?/ x% H$ r" T. \' ?GetPaletteEntries(hPal, 0, nColors, (LPPALETTEENTRY)&pAnimate);
CPalette *pOldPalette = pDC->SelectPalette(&pal, FALSE);
pDC->RealizePalette();
/ Y$ A- q1 J. L5 r+ ]5 T6 aCDC memDC;
memDC.CreateCompatibleDC( pDC );
CBitmap bmp;
bmp.CreateCompatibleBitmap( pDC, nWidth, nHeight );
CBitmap *pOldBitmap = memDC.SelectObject( &bmp );
CPalette *pOldMemPalette = memDC.SelectPalette(&pal, FALSE);
8 D! G' Z3 h. z8 l! y/ `4 ^memDC.RealizePalette();
::SetDIBitsToDevice(memDC.m_hDC,0,0,nWidth,nHeight,0,0,0,nHeight,lpDIBBits,(LPBITMAPINFO)hDIB,DIB_RGB_COLORS);
! e8 u; }1 P/ o& ]9 a2 UAnimatePalette(hPal, 0, nColors, (LPPALETTEENTRY)&pAnimate);
pDC->BitBlt(xDest, yDest, nWidth, nHeight, &memDC,0,0,SRCCOPY );
// 淡入淡出
. E+ Q& ~) |! q9 \! J) |; P6 x. }for( i=1; i <= nLoops; i++ )
4 v$ A: O) w* k+ ^1 j( c* gfor (j = 0; j < nColors; j++)
8 I4 q- E7 y8 A# p/ z2 [$ Kif(nFlag==1)
pAnimate[j].peRed = clrRValue - ((clrRValue-pOriginal[j].peRed)*i)/nLoops;
( ~* i# t" B. ?4 tpAnimate[j].peGreen = clrGValue - ((clrGValue-pOriginal[j].peGreen)*i)/nLoops;
) B. C& ?+ K. i, Q9 dpAnimate[j].peBlue = clrBValue - ((clrBValue-pOriginal[j].peBlue)*i)/nLoops;
# [9 U; H/ f9 B- K2 G7 c( ]else
pAnimate[j].peRed = pOriginal[j].peRed - ((pOriginal[j].peRed - clrRValue)*i)/nLoops;
pAnimate[j].peGreen = pOriginal[j].peGreen - ((pOriginal[j].peGreen - clrGValue)*i)/nLoops;
, Y: a8 v# k  K% t$ {- F& ^( zpAnimate[j].peBlue = pOriginal[j].peBlue - ((pOriginal[j].peBlue - clrBValue)*i)/nLoops;
pal.AnimatePalette(0, nColors, (LPPALETTEENTRY)&pAnimate);
9 G1 g# t( m- J. ^// Delay...
/ X2 M0 t8 H- I$ Y" g: a2 S) c7 WSleep(nDelay);
memDC.SelectPalette(pOldMemPalette, FALSE);
1 N/ L% a# P% y" @3 E1 V& d6 PmemDC.SelectObject( pOldBitmap );
pDC->SelectPalette(pOldPalette, FALSE);
) j; `4 H6 |. b2 ?else if( (pDC->GetDeviceCaps(RASTERCAPS) & RC_PALETTE) == 0 && nColors <= 256 )
* z3 p7 P3 F" P+ [" ~for( int i=0; i < nColors; i++)
: d3 d% G( }/ {7 A; cpOriginal.peRed = bmInfo.bmiColors.rgbRed ;
pOriginal.peGreen = bmInfo.bmiColors.rgbGreen;
pOriginal.peBlue = bmInfo.bmiColors.rgbBlue ;
" ?+ ^  j" p& }% Y' f% L4 ]if(nFlag==1)
0 o: o- ?8 U: z) ^bmInfo.bmiColors.rgbRed = clrRValue;
bmInfo.bmiColors.rgbGreen = clrGValue;
bmInfo.bmiColors.rgbBlue = clrBValue;
::SetDIBitsToDevice(pDC->m_hDC,0,0,nWidth,nHeight,0,0,0,nHeight,lpDIBBits,(LPBITMAPINFO)hDIB,DIB_RGB_COLORS);
/ Q2 E' H' b, x* O+ [// 淡入淡出
; B/ s: h7 H8 i* @; S8 ufor( i=1; i <= nLoops; i++ )
9 a. `( K7 r4 n  A+ h4 lfor (j = 0; j < nColors; j++)
2 e3 [! B4 @6 v) i; tif(nFlag==1)
bmInfo.bmiColors[j].rgbRed = clrRValue - ((clrRValue-pOriginal[j].peRed)*i)/nLoops;
% S2 T% k$ D# G8 c5 \bmInfo.bmiColors[j].rgbGreen = clrGValue - ((clrGValue-pOriginal[j].peGreen)*i)/nLoops;
0 |. \' L: P% EbmInfo.bmiColors[j].rgbBlue = clrBValue - ((clrBValue-pOriginal[j].peBlue)*i)/nLoops;
else
bmInfo.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;
. v. b4 N6 y7 J) LbmInfo.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);
$ y3 \; H& W3 p// Delay...
- V3 Z3 W5 X& l, qSleep(nDelay);