指定背景的淡入淡出

天云上人

创建步骤：
7 u, P6 ]) D' R  g  [: ^( t1、如果系统支持调色板，创建动态调色板pAnimate与初始调色板pOriginal。
( ]# L9 c+ Q  Q$ i+ G, U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
$ ?. x9 f) T: w2 A0 N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
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
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
: i7 @5 P* M# b/ K5 V7 j  v' w//参数说明：
//hDIB -位图句柄
9 O) S4 b3 K( t8 p- N5 u//color -指定背景色
  h$ `; c* Y1 n. n& s5 m//xDest -显示位图的左上角x坐标
//yDest -显示位图的左上角y坐标
+ l- S/ h4 d" ^  p. [//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,
! [* l) m3 {+ |2 ]$ V( yint nLoops, int nDelay ,int nFlag)
7 Z* D# Q* f" A' z7 m3 ~int i,j;
: N  m( Z2 y: _4 q  a( ^) mHPALETTE hPal;
PALETTEENTRY pAnimate[256];
5 d" I: ?9 H' l2 kPALETTEENTRY pOriginal[256];
CPalette pal;
// 创建236色调色板
) j1 i8 j3 c' M% {　
BITMAPINFO &bmInfo = *(LPBITMAPINFO)hDIB ;
　
8 O% \8 Y* p8 u$ zint nColors = bmInfo.bmiHeader.biClrUsed ? bmInfo.bmiHeader.biClrUsed :
" e, y: i  ^4 x1 << bmInfo.bmiHeader.biBitCount;
int nWidth = bmInfo.bmiHeader.biWidth;
+ Z6 H2 f: k3 Cint nHeight = bmInfo.bmiHeader.biHeight;
( O  J6 \6 \. V! {9 f. LLPVOID lpDIBBits = (LPVOID)(bmInfo.bmiColors + nColors);
0 `  a1 b+ Z7 Q1 Q# ?int clrRValue = GetRValue(color);
2 i3 y0 J* v: ~- n7 @0 u" }$ }int clrGValue = GetGValue(color);
int clrBValue = GetBValue(color);
1 G# C- O8 }" {9 W. ?6 Bif( pDC->GetDeviceCaps(RASTERCAPS) & RC_PALETTE && nColors <= 256 )
if (!(hPal = Create236Palette(hDIB)))
( r5 C. N+ }% R% T. b. o7 A! breturn;
9 j0 x$ K1 v+ Qpal.Attach( hPal );
2 f" f2 F) g# V3 I1 V1 b+ u// 得到调色板初始值
& e- V. G  ^  ]! B- \) x; mGetPaletteEntries(hPal, 0, nColors, (LPPALETTEENTRY)&pOriginal);
  R0 C' K: x( T+ V// 设定动态调色板初始值为指定色
if(nFlag==1)
for (j = 0; j < nColors; j++)
$ V# ?. y$ j+ N, G0 FpAnimate[j].peRed = clrRValue;
+ V1 A3 p) u6 w* JpAnimate[j].peGreen = clrGValue;
: A1 p5 T1 }/ s/ A1 M5 l  ipAnimate[j].peBlue = clrBValue;
8 W# X5 t. J; T; q2 MpAnimate[j].peFlags = PC_RESERVED;
/ c& e+ k3 b: Z' Y; {else
GetPaletteEntries(hPal, 0, nColors, (LPPALETTEENTRY)&pAnimate);
CPalette *pOldPalette = pDC->SelectPalette(&pal, FALSE);
pDC->RealizePalette();
CDC memDC;
memDC.CreateCompatibleDC( pDC );
CBitmap bmp;
) z' s& D- M$ Y8 C# k6 Q$ ?1 [bmp.CreateCompatibleBitmap( pDC, nWidth, nHeight );
CBitmap *pOldBitmap = memDC.SelectObject( &bmp );
CPalette *pOldMemPalette = memDC.SelectPalette(&pal, FALSE);
memDC.RealizePalette();
2 ]; j$ A; l1 [2 A% X, \0 r::SetDIBitsToDevice(memDC.m_hDC,0,0,nWidth,nHeight,0,0,0,nHeight,lpDIBBits,(LPBITMAPINFO)hDIB,DIB_RGB_COLORS);
AnimatePalette(hPal, 0, nColors, (LPPALETTEENTRY)&pAnimate);
. p$ R6 g4 |9 q, `, r7 S& FpDC->BitBlt(xDest, yDest, nWidth, nHeight, &memDC,0,0,SRCCOPY );
: \  E: N1 {6 u3 ]// 淡入淡出
for( i=1; i <= nLoops; i++ )
for (j = 0; j < nColors; j++)
if(nFlag==1)
pAnimate[j].peRed = clrRValue - ((clrRValue-pOriginal[j].peRed)*i)/nLoops;
8 u6 y2 J  A* G6 [/ ?1 gpAnimate[j].peGreen = clrGValue - ((clrGValue-pOriginal[j].peGreen)*i)/nLoops;
pAnimate[j].peBlue = clrBValue - ((clrBValue-pOriginal[j].peBlue)*i)/nLoops;
* b& r4 O& ~3 \6 m: q: ]6 nelse
pAnimate[j].peRed = pOriginal[j].peRed - ((pOriginal[j].peRed - clrRValue)*i)/nLoops;
pAnimate[j].peGreen = pOriginal[j].peGreen - ((pOriginal[j].peGreen - clrGValue)*i)/nLoops;
+ E0 N" e" `( G8 XpAnimate[j].peBlue = pOriginal[j].peBlue - ((pOriginal[j].peBlue - clrBValue)*i)/nLoops;
6 s5 R' m5 T3 s1 c* N' lpal.AnimatePalette(0, nColors, (LPPALETTEENTRY)&pAnimate);
// Delay...
Sleep(nDelay);
memDC.SelectPalette(pOldMemPalette, FALSE);
memDC.SelectObject( pOldBitmap );
1 y5 [6 _3 M4 d' w! OpDC->SelectPalette(pOldPalette, FALSE);
/ A4 i# a3 P. k; ?" N% Welse if( (pDC->GetDeviceCaps(RASTERCAPS) & RC_PALETTE) == 0 && nColors <= 256 )
9 a+ D+ t- }3 L4 Hfor( int i=0; i < nColors; i++)
" U  w- V& E8 H4 x( S! {% ApOriginal.peRed = bmInfo.bmiColors.rgbRed ;
  d- P4 W0 I, g$ @( qpOriginal.peGreen = bmInfo.bmiColors.rgbGreen;
pOriginal.peBlue = bmInfo.bmiColors.rgbBlue ;
3 a3 D2 o7 D, Y. E4 _8 _7 s1 _if(nFlag==1)
bmInfo.bmiColors.rgbRed = clrRValue;
bmInfo.bmiColors.rgbGreen = clrGValue;
5 C0 J% i2 E5 ]) j1 E! `  A5 KbmInfo.bmiColors.rgbBlue = clrBValue;
::SetDIBitsToDevice(pDC->m_hDC,0,0,nWidth,nHeight,0,0,0,nHeight,lpDIBBits,(LPBITMAPINFO)hDIB,DIB_RGB_COLORS);
$ Z& G# P4 @* |% d8 @# E3 [4 h0 O// 淡入淡出
) }" m, Y/ o7 mfor( i=1; i <= nLoops; i++ )
for (j = 0; j < nColors; j++)
if(nFlag==1)
4 A" d) T  I( e8 t1 _0 rbmInfo.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;
else
bmInfo.bmiColors[j].rgbRed = pOriginal[j].peRed - ((pOriginal[j].peRed-clrRValue)*i)/nLoops;
2 E( C- p0 t/ H" C; }- jbmInfo.bmiColors[j].rgbGreen = pOriginal[j].peGreen - ((pOriginal[j].peGreen-clrGValue)*i)/nLoops;
; x* l6 m/ B$ N2 E+ R& tbmInfo.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);
// Delay...
2 q7 {  n5 D5 Q, [Sleep(nDelay);