Diblook Dib的使用

// dibapi.cpp // // Source file for Device-Independent Bitmap (DIB) API. Provides // the following functions: // // PaintDIB() - Painting routine for a DIB // CreateDIBPalette() - Creates a palette from a DIB // FindDIBBits() - Returns a pointer to the DIB bits // DIBWidth() - Gets the width of the DIB // DIBHeight() - Gets the height of the DIB // PaletteSize() - Gets the size required to store the DIB's palette // DIBNumColors() - Calculates the number of colors // in the DIB's color table // CopyHandle() - Makes a copy of the given global memory block // // This is a part of the Microsoft Foundation Classes C++ library. // Copyright (c) Microsoft Corporation. All rights reserved. // // This source code is only intended as a supplement to the // Microsoft Foundation Classes Reference and related // electronic documentation provided with the library. // See these sources for detailed information regarding the // Microsoft Foundation Classes product. #include "stdafx.h" #include "dibapi.h" #include <io.h> #include <errno.h> /************************************************************************* * * PaintDIB() * * Parameters: * * HDC hDC - DC to do output to * * LPRECT lpDCRect - rectangle on DC to do output to * * HDIB hDIB - handle to global memory with a DIB spec * in it followed by the DIB bits * * LPRECT lpDIBRect - rectangle of DIB to output into lpDCRect * * CPalette* pPal - pointer to CPalette containing DIB's palette * * Return Value: * * BOOL - TRUE if DIB was drawn, FALSE otherwise * * Description: * Painting routine for a DIB. Calls StretchDIBits() or * SetDIBitsToDevice() to paint the DIB. The DIB is * output to the specified DC, at the coordinates given * in lpDCRect. The area of the DIB to be output is * given by lpDIBRect. * ************************************************************************/ BOOL WINAPI PaintDIB(HDC hDC, LPRECT lpDCRect, HDIB hDIB, LPRECT lpDIBRect, CPalette* pPal) { LPSTR lpDIBHdr; // Pointer to BITMAPINFOHEADER LPSTR lpDIBBits; // Pointer to DIB bits BOOL bSuccess=FALSE; // Success/fail flag HPALETTE hPal=NULL; // Our DIB's palette HPALETTE hOldPal=NULL; // Previous palette /* Check for valid DIB handle */ if (hDIB == NULL) return FALSE; /* Lock down the DIB, and get a pointer to the beginning of the bit * buffer */ lpDIBHdr = (LPSTR) ::GlobalLock((HGLOBAL) hDIB); lpDIBBits = ::FindDIBBits(lpDIBHdr); // Get the DIB's palette, then select it into DC if (pPal != NULL) { hPal = (HPALETTE) pPal->m_hObject; // Select as background since we have // already realized in forground if needed hOldPal = ::SelectPalette(hDC, hPal, TRUE); } /* Make sure to use the stretching mode best for color pictures */ ::SetStretchBltMode(hDC, COLORONCOLOR); /* Determine whether to call StretchDIBits() or SetDIBitsToDevice() */ if ((RECTWIDTH(lpDCRect) == RECTWIDTH(lpDIBRect)) && (RECTHEIGHT(lpDCRect) == RECTHEIGHT(lpDIBRect))) bSuccess = ::SetDIBitsToDevice(hDC, // hDC lpDCRect->left, // DestX lpDCRect->top, // DestY RECTWIDTH(lpDCRect), // nDestWidth RECTHEIGHT(lpDCRect), // nDestHeight lpDIBRect->left, // SrcX (int)DIBHeight(lpDIBHdr) - lpDIBRect->top - RECTHEIGHT(lpDIBRect), // SrcY 0, // nStartScan (WORD)DIBHeight(lpDIBHdr), // nNumScans lpDIBBits, // lpBits (LPBITMAPINFO)lpDIBHdr, // lpBitsInfo DIB_RGB_COLORS); // wUsage else bSuccess = ::StretchDIBits(hDC, // hDC lpDCRect->left, // DestX lpDCRect->top, // DestY RECTWIDTH(lpDCRect), // nDestWidth RECTHEIGHT(lpDCRect), // nDestHeight lpDIBRect->left, // SrcX lpDIBRect->top, // SrcY RECTWIDTH(lpDIBRect), // wSrcWidth RECTHEIGHT(lpDIBRect), // wSrcHeight lpDIBBits, // lpBits (LPBITMAPINFO)lpDIBHdr, // lpBitsInfo DIB_RGB_COLORS, // wUsage SRCCOPY); // dwROP ::GlobalUnlock((HGLOBAL) hDIB); /* Reselect old palette */ if (hOldPal != NULL) { ::SelectPalette(hDC, hOldPal, TRUE); } return bSuccess; } /************************************************************************* * * CreateDIBPalette() * * Parameter: * * HDIB hDIB - specifies the DIB * * Return Value: * * HPALETTE - specifies the palette * * Description: * * This function creates a palette from a DIB by allocating memory for the * logical palette, reading and storing the colors from the DIB's color table * into the logical palette, creating a palette from this logical palette, * and then returning the palette's handle. This allows the DIB to be * displayed using the best possible colors (important for DIBs with 256 or * more colors). * ************************************************************************/ BOOL WINAPI CreateDIBPalette(HDIB hDIB, CPalette* pPal) { LPLOGPALETTE lpPal; // pointer to a logical palette HANDLE hLogPal; // handle to a logical palette int i; // loop index WORD wNumColors; // number of colors in color table LPSTR lpbi; // pointer to packed-DIB LPBITMAPINFO lpbmi; // pointer to BITMAPINFO structure (Win3.0) LPBITMAPCOREINFO lpbmc; // pointer to BITMAPCOREINFO structure (old) BOOL bWinStyleDIB; // flag which signifies whether this is a Win3.0 DIB BOOL bResult = FALSE; /* if handle to DIB is invalid, return FALSE */ if (hDIB == NULL) return FALSE; lpbi = (LPSTR) ::GlobalLock((HGLOBAL) hDIB); /* get pointer to BITMAPINFO (Win 3.0) */ lpbmi = (LPBITMAPINFO)lpbi; /* get pointer to BITMAPCOREINFO (old 1.x) */ lpbmc = (LPBITMAPCOREINFO)lpbi; /* get the number of colors in the DIB */ wNumColors = ::DIBNumColors(lpbi); if (wNumColors != 0) { /* allocate memory block for logical palette */ hLogPal = ::GlobalAlloc(GHND, sizeof(LOGPALETTE) + sizeof(PALETTEENTRY) * wNumColors); /* if not enough memory, clean up and return NULL */ if (hLogPal == 0) { ::GlobalUnlock((HGLOBAL) hDIB); return FALSE; } lpPal = (LPLOGPALETTE) ::GlobalLock((HGLOBAL) hLogPal); /* set version and number of palette entries */ lpPal->palVersion = PALVERSION; lpPal->palNumEntries = (WORD)wNumColors; /* is this a Win 3.0 DIB? */ bWinStyleDIB = IS_WIN30_DIB(lpbi); for (i = 0; i < (int)wNumColors; i++) { if (bWinStyleDIB) { lpPal->palPalEntry[i].peRed = lpbmi->bmiColors[i].rgbRed; lpPal->palPalEntry[i].peGreen = lpbmi->bmiColors[i].rgbGreen; lpPal->palPalEntry[i].peBlue = lpbmi->bmiColors[i].rgbBlue; lpPal->palPalEntry[i].peFlags = 0; } else { lpPal->palPalEntry[i].peRed = lpbmc->bmciColors[i].rgbtRed; lpPal->palPalEntry[i].peGreen = lpbmc->bmciColors[i].rgbtGreen; lpPal->palPalEntry[i].peBlue = lpbmc->bmciColors[i].rgbtBlue; lpPal->palPalEntry[i].peFlags = 0; } } /* create the palette and get handle to it */ bResult = pPal->CreatePalette(lpPal); ::GlobalUnlock((HGLOBAL) hLogPal); ::GlobalFree((HGLOBAL) hLogPal); } ::GlobalUnlock((HGLOBAL) hDIB);