02: 
03: LONG xStart, LONG yStart, COLORREF cTransparentColor)  
04: {  
05:         BITMAP bm;  
06:         COLORREF cColor;  
07:         HBITMAP bmAndBack, bmAndObject, bmAndMem, bmSave;  
08:         HBITMAP bmBackOld, bmObjectOld, bmMemOld, bmSaveOld;  
09:         HDC hdcMem, hdcBack, hdcObject, hdcTemp, hdcSave;  
10:         POINT ptSize;  
11:           
12:         hdcTemp = CreateCompatibleDC(hdc);  
13:         SelectObject(hdcTemp, hBitmap); // Select the bitmap  
14:           
15:         GetObject(hBitmap, sizeof(BITMAP), (LPSTR)&bm);  
16:         ptSize.x = bm.bmWidth; // Get width of bitmap  
17:         ptSize.y = bm.bmHeight; // Get height of bitmap  
18:         DPtoLP(hdcTemp, &ptSize, 1); // Convert from device  
19:         // to logical points  
20:           
21:         // Create some DCs to hold temporary data.  
22:         hdcBack = CreateCompatibleDC(hdc);  
23:         hdcObject = CreateCompatibleDC(hdc);  
24:         hdcMem = CreateCompatibleDC(hdc);  
25:         hdcSave = CreateCompatibleDC(hdc);  
26:           
27:         // Create a bitmap for each DC. DCs are required for a number of  
28:         // GDI functions.  
29:           
30:         // Monochrome DC  
31:         bmAndBack = CreateBitmap(ptSize.x, ptSize.y, 1, 1, NULL);  
32:           
33:         // Monochrome DC  
34:         bmAndObject = CreateBitmap(ptSize.x, ptSize.y, 1, 1, NULL);  
35:           
36:         bmAndMem = CreateCompatibleBitmap(hdc, ptSize.x, ptSize.y);  
37:         bmSave = CreateCompatibleBitmap(hdc, ptSize.x, ptSize.y);  
38:           
39:         // Each DC must select a bitmap object to store pixel data.  
40:         bmBackOld = (HBITMAP)SelectObject(hdcBack, bmAndBack);  
41:         bmObjectOld = (HBITMAP)SelectObject(hdcObject, bmAndObject);  
42:         bmMemOld = (HBITMAP)SelectObject(hdcMem, bmAndMem);  
43:         bmSaveOld = (HBITMAP)SelectObject(hdcSave, bmSave);  
44:           
45:         // Set proper mapping mode.  
46:         SetMapMode(hdcTemp, GetMapMode(hdc));  
47:           
48:         // Save the bitmap sent here, because it will be overwritten.  
49:         BitBlt(hdcSave, 0, 0, ptSize.x, ptSize.y, hdcTemp, 0, 0, SRCCOPY);  
50:           
51:         // Set the background color of the source DC to the color.  
52:         // contained in the parts of the bitmap that should be transparent  
53:         cColor = SetBkColor(hdcTemp, cTransparentColor);  
54:           
55:         // Create the object mask for the bitmap by performing a BitBlt  
56:         // from the source bitmap to a monochrome bitmap.  
57:         BitBlt(hdcObject, 0, 0, ptSize.x, ptSize.y, hdcTemp, 0, 0,   
58:         SRCCOPY);  
59:           
60:         // Set the background color of the source DC back to the original  
61:         // color.  
62:         SetBkColor(hdcTemp, cColor);  
63:           
64:         // Create the inverse of the object mask.  
65:         BitBlt(hdcBack, 0, 0, ptSize.x, ptSize.y, hdcObject, 0, 0,   
66:         NOTSRCCOPY);  
67:           
68:         // Copy the background of the main DC to the destination.  
69:         BitBlt(hdcMem, 0, 0, ptSize.x, ptSize.y, hdc, xStart, yStart,   
70:         SRCCOPY);  
71:           
72:         // Mask out the places where the bitmap will be placed.  
73:         BitBlt(hdcMem, 0, 0, ptSize.x, ptSize.y, hdcObject, 0, 0, SRCAND);  
74:           
75:         // Mask out the transparent colored pixels on the bitmap.  
76:         BitBlt(hdcTemp, 0, 0, ptSize.x, ptSize.y, hdcBack, 0, 0, SRCAND);  
77:           
78:         // XOR the bitmap with the background on the destination DC.  
79:         BitBlt(hdcMem, 0, 0, ptSize.x, ptSize.y, hdcTemp, 0, 0, SRCPAINT);  
80:           
81:         // Copy the destination to the screen.  
82:         BitBlt(hdc, xStart, yStart, ptSize.x, ptSize.y, hdcMem, 0, 0,   
83:         SRCCOPY);  
84:           
85:         // Place the original bitmap back into the bitmap sent here.  
86:         BitBlt(hdcTemp, 0, 0, ptSize.x, ptSize.y, hdcSave, 0, 0, SRCCOPY);  
87:           
88:         // Delete the memory bitmaps.  
89:         DeleteObject(SelectObject(hdcBack, bmBackOld));  
90:         DeleteObject(SelectObject(hdcObject, bmObjectOld));  
91:         DeleteObject(SelectObject(hdcMem, bmMemOld));  
92:         DeleteObject(SelectObject(hdcSave, bmSaveOld));  
93:           
94:         // Delete the memory DCs.  
95:         DeleteDC(hdcMem);  
96:         DeleteDC(hdcBack);  
97:         DeleteDC(hdcObject);  
98:         DeleteDC(hdcSave);  
99:         DeleteDC(hdcTemp);  
100: }