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了一個圖片（稱爲i_MC），我就可以畫一個簡單的圖像（m_ImgMCN）做：特殊繪製透明圖片
Call i_MC.PaintPicture(m_ImgMCN, 0, 0, i_MC.width, i_MC.height)
現在我想提出一個透明的圖像上這張照片，在具體位置。我發現了一個示例代碼，它能夠很好地解決一個問題：不應該透過第二張（透明）圖像透支的部分圖像會以純黑色透支。
如果通過設置Picture-property來繪製上面的背景圖像，則算法可以很好地工作。不能做到這一點，因爲這不允許任何拉伸。
透明圖像是一個簡單的圖像，比包含被遮罩的顏色的框更小。我用以下示例代碼（.AutoRedraw =適用於所有盒子和.ScaleMode = 3「像素）：
Option Explicit
Private Declare Function BitBlt Lib "gdi32" (ByVal hDCDest As _
Long, ByVal XDest As Long, ByVal YDest As Long, ByVal _
nWidth As Long, ByVal nHeight As Long, ByVal hDCSrc _
As Long, ByVal XSrc As Long, ByVal YSrc As Long, ByVal _
dwRop As Long) As Long
Private Declare Function CreateBitmap Lib "gdi32" (ByVal nWidth _
As Long, ByVal nHeight As Long, ByVal nPlanes As Long, _
ByVal nBitCount As Long, lpBits As Any) As Long
Private Declare Function SetBkColor Lib "gdi32" (ByVal hdc As _
Long, ByVal crColor As Long) As Long
Private Declare Function SelectObject Lib "gdi32" (ByVal hdc As _
Long, ByVal hObject As Long) As Long
Private Declare Function CreateCompatibleBitmap Lib "gdi32" (ByVal _
hdc As Long, ByVal nWidth As Long, ByVal nHeight As Long) _
As Long
Private Declare Function CreateCompatibleDC Lib "gdi32" (ByVal hdc _
As Long) As Long
Private Declare Function DeleteDC Lib "gdi32" (ByVal hdc As Long) _
As Long
Private Declare Function DeleteObject Lib "gdi32" (ByVal hObject _
As Long) As Long
Private Type RECT
Left As Long
Top As Long
Right As Long
Bottom As Long
End Type
Dim R As RECT
Private Sub TranspPic(OutDstDC&, DstDC&, SrcDC&, SrcRect _
As RECT, ByVal DstX&, ByVal DstY&, _
TransColor&)
Dim Result&, W&, H&
Dim MonoMaskDC&, hMonoMask&, MonoInvDC&, hMonoInv&
Dim ResultDstDC&, hResultDst&, ResultSrcDC&, hResultSrc&
Dim hPrevMask&, hPrevInv&, hPrevSrc&, hPrevDst&
W = SrcRect.Right - SrcRect.Left
H = SrcRect.Bottom - SrcRect.Top
'Generieren einer Monochromen & einer inversen Maske
MonoMaskDC = CreateCompatibleDC(DstDC)
MonoInvDC = CreateCompatibleDC(DstDC)
hMonoMask = CreateBitmap(W, H, 1, 1, ByVal 0&)
hMonoInv = CreateBitmap(W, H, 1, 1, ByVal 0&)
hPrevMask = SelectObject(MonoMaskDC, hMonoMask)
hPrevInv = SelectObject(MonoInvDC, hMonoInv)
'Puffer erstellen
ResultDstDC = CreateCompatibleDC(DstDC)
ResultSrcDC = CreateCompatibleDC(DstDC)
hResultDst = CreateCompatibleBitmap(DstDC, W, H)
hResultSrc = CreateCompatibleBitmap(DstDC, W, H)
hPrevDst = SelectObject(ResultDstDC, hResultDst)
hPrevSrc = SelectObject(ResultSrcDC, hResultSrc)
'Sourcebild in die monochrome Maske kopieren
Dim OldBC As Long
OldBC = SetBkColor(SrcDC, TransColor)
Result = BitBlt(MonoMaskDC, 0, 0, W, H, SrcDC, _
SrcRect.Left, SrcRect.Top, vbSrcCopy)
TransColor = SetBkColor(SrcDC, OldBC)
'Inverse Maske erstellen
Result = BitBlt(MonoInvDC, 0, 0, W, H, _
MonoMaskDC, 0, 0, vbNotSrcCopy)
'Hintergrund des Zielbildes auslesen
Result = BitBlt(ResultDstDC, 0, 0, W, H, _
DstDC, DstX, DstY, vbSrcCopy)
'AND mit der Maske
Result = BitBlt(ResultDstDC, 0, 0, W, H, _
MonoMaskDC, 0, 0, vbSrcAnd)
'Überlappung des Sourcebildes mit dem Zielbild auslesen
Result = BitBlt(ResultSrcDC, 0, 0, W, H, SrcDC, _
SrcRect.Left, SrcRect.Top, vbSrcCopy)
'AND mit der invertierten, monochromen Maske
Result = BitBlt(ResultSrcDC, 0, 0, W, H, _
MonoInvDC, 0, 0, vbSrcAnd)
'XOR mit beiden
Result = BitBlt(ResultDstDC, 0, 0, W, H, _
ResultSrcDC, 0, 0, vbSrcInvert)
'Ergebnis in das Zielbild kopieren
Result = BitBlt(OutDstDC, DstX, DstY, W, H, _
ResultDstDC, 0, 0, vbSrcCopy)
'Erstellte Objekte & DCs wieder freigeben
hMonoMask = SelectObject(MonoMaskDC, hPrevMask)
DeleteObject hMonoMask
DeleteDC MonoMaskDC
hMonoInv = SelectObject(MonoInvDC, hPrevInv)
DeleteObject hMonoInv
DeleteDC MonoInvDC
hResultDst = SelectObject(ResultDstDC, hPrevDst)
DeleteObject hResultDst
DeleteDC ResultDstDC
hResultSrc = SelectObject(ResultSrcDC, hPrevSrc)
DeleteObject hResultSrc
DeleteDC ResultSrcDC
End Sub
Private Sub MovePicTo(ByVal X&, ByVal Y&)
i_MC.Cls
picSrc.Picture = m_ImgMCN
With R
.Left = 0
.Top = 0
.Right = Picture2.ScaleWidth
.Bottom = Picture2.ScaleHeight
End With
Call TranspPic(i_MC.hdc, i_MC.hdc, picSrc.hdc, R, X, Y, vbWhite)
i_MC.Refresh
DoEvents
End Sub
此代碼最初駐留在activevb.de，我修改它一點點不改變算法或功能。我可能會發布鏈接到原始文章。
沒有成功，我試圖修改尺寸不同的中間的照片，但它一直畫的圖像錯誤：
其中透明像素繪製正確的圖像部分，背景是包括在內。圖片的其餘部分（算法不應觸及的部分）被黑色覆蓋。
任何想法是讚賞。一個算法來繪製24位的alphablended圖像也不錯！我搜索了很長時間，沒有找到一段代碼。
PS：這是普通的舊VB6，移動到.NET或任何其他語言不幸是不是一種選擇。
在此先感謝和問候