DIBAPI.CPP

//  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) 1992 Microsoft Corporation
// All rights reserved.
//
// This source code is only intended as a supplement to the
// Microsoft Foundation Classes Reference and Microsoft
// QuickHelp and/or WinHelp 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 "mystrlst.h"
#include "structs.h"

extern _gconfig gc;

/*************************************************************************
 *
 * 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,
					char    *memp,
					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 (!memp)
		return FALSE;

	/* Lock down the DIB, and get a pointer to the beginning of the bit
	 *  buffer
	 */
	lpDIBHdr  = (LPSTR) memp;

	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);
	}

	RealizePalette(hDC);
	/* 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) && 
	   !gc.bmps_size)
		bSuccess = ::SetDIBitsToDevice(hDC,lpDCRect->left,lpDCRect->top,RECTWIDTH(lpDCRect),
			RECTHEIGHT(lpDCRect),lpDIBRect->left,
			(int)DIBHeight(lpDIBHdr)-lpDIBRect->top-RECTHEIGHT(lpDIBRect),0,
			(WORD)DIBHeight(lpDIBHdr),lpDIBBits,(LPBITMAPINFO)lpDIBHdr,DIB_RGB_COLORS);
   else
   {
		double w;
		double h;
		switch (gc.bmps_size)
		{
			case 0:
			default:
				w=RECTWIDTH(lpDCRect);
				h=RECTHEIGHT(lpDCRect);
				break;
			case 1:
				w=(double)RECTWIDTH(lpDCRect)/1.5;
				h=(double)RECTHEIGHT(lpDCRect)/1.5;
				break;
			case 2:
				w=(double)RECTWIDTH(lpDCRect)/2;
				h=(double)RECTHEIGHT(lpDCRect)/2;
				break;
			case 3:
				w=(double)RECTWIDTH(lpDCRect)/2.8;
				h=(double)RECTHEIGHT(lpDCRect)/2.8;
				break;
		}

	  bSuccess = ::StretchDIBits(hDC,lpDCRect->left,lpDCRect->top,(int) w,(int) h,
							   lpDIBRect->left,lpDIBRect->top,RECTWIDTH(lpDIBRect),RECTHEIGHT(lpDIBRect),
							   lpDIBBits,(LPBITMAPINFO)lpDIBHdr,DIB_RGB_COLORS,SRCCOPY);
    }
	/* 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(char *memp, CPalette* pPal)
{
	LPLOGPALETTE lpPal;      // pointer to a logical palette
	HANDLE hLogPal;          // handle to a logical palette
	HPALETTE hPal = NULL;    // handle to a 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 (!memp)
	  return FALSE;

   lpbi = (LPSTR) memp;

   /* 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)
	  wNumColors=256;

   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)
			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);
	}

	return bResult;
}

/*************************************************************************
 *
 * FindDIBBits()
 *
 * Parameter:
 *
 * LPSTR lpbi       - pointer to packed-DIB memory block
 *
 * Return Value:
 *
 * LPSTR            - pointer to the DIB bits
 *
 * Description:
 *
 * This function calculates the address of the DIB's bits and returns a
 * pointer to the DIB bits.
 *
 ************************************************************************/


LPSTR WINAPI FindDIBBits(LPSTR lpbi)
{
	return (lpbi + *(LPDWORD)lpbi + ::PaletteSize(lpbi));
}


/*************************************************************************
 *
 * DIBWidth()
 *
 * Parameter:
 *
 * LPSTR lpbi       - pointer to packed-DIB memory block
 *
 * Return Value:
 *
 * DWORD            - width of the DIB
 *
 * Description:
 *
 * This function gets the width of the DIB from the BITMAPINFOHEADER
 * width field if it is a Windows 3.0-style DIB or from the BITMAPCOREHEADER
 * width field if it is an other-style DIB.
 *
 ************************************************************************/


DWORD WINAPI DIBWidth(LPSTR lpDIB)
{
	LPBITMAPINFOHEADER lpbmi;  // pointer to a Win 3.0-style DIB
	LPBITMAPCOREHEADER lpbmc;  // pointer to an other-style DIB

	/* point to the header (whether Win 3.0 and old) */

	lpbmi = (LPBITMAPINFOHEADER)lpDIB;
	lpbmc = (LPBITMAPCOREHEADER)lpDIB;

	/* return the DIB width if it is a Win 3.0 DIB */
	if (IS_WIN30_DIB(lpDIB))
		return lpbmi->biWidth;
	else  /* it is an other-style DIB, so return its width */
		return (DWORD)lpbmc->bcWidth;
}


/*************************************************************************
 *
 * DIBHeight()
 *
 * Parameter:
 *
 * LPSTR lpbi       - pointer to packed-DIB memory block
 *
 * Return Value:
 *
 * DWORD            - height of the DIB
 *
 * Description:
 *
 * This function gets the height of the DIB from the BITMAPINFOHEADER
 * height field if it is a Windows 3.0-style DIB or from the BITMAPCOREHEADER
 * height field if it is an other-style DIB.
 *
 ************************************************************************/


DWORD WINAPI DIBHeight(LPSTR lpDIB)
{
	LPBITMAPINFOHEADER lpbmi;  // pointer to a Win 3.0-style DIB
	LPBITMAPCOREHEADER lpbmc;  // pointer to an other-style DIB

	/* point to the header (whether old or Win 3.0 */

	lpbmi = (LPBITMAPINFOHEADER)lpDIB;
	lpbmc = (LPBITMAPCOREHEADER)lpDIB;

	/* return the DIB height if it is a Win 3.0 DIB */
	if (IS_WIN30_DIB(lpDIB))
		return lpbmi->biHeight;
	else  /* it is an other-style DIB, so return its height */
		return (DWORD)lpbmc->bcHeight;
}


/*************************************************************************
 *
 * PaletteSize()
 *
 * Parameter:
 *
 * LPSTR lpbi       - pointer to packed-DIB memory block
 *
 * Return Value:
 *
 * WORD             - size of the color palette of the DIB
 *
 * Description:
 *
 * This function gets the size required to store the DIB's palette by
 * multiplying the number of colors by the size of an RGBQUAD (for a
 * Windows 3.0-style DIB) or by the size of an RGBTRIPLE (for an other-
 * style DIB).
 *
 ************************************************************************/


WORD WINAPI PaletteSize(LPSTR lpbi)
{
   /* calculate the size required by the palette */
   if (IS_WIN30_DIB (lpbi))
	  return (WORD)(::DIBNumColors(lpbi) * sizeof(RGBQUAD));
   else
	  return (WORD)(::DIBNumColors(lpbi) * sizeof(RGBTRIPLE));
}


/*************************************************************************
 *
 * DIBNumColors()
 *
 * Parameter:
 *
 * LPSTR lpbi       - pointer to packed-DIB memory block
 *
 * Return Value:
 *
 * WORD             - number of colors in the color table
 *
 * Description:
 *
 * This function calculates the number of colors in the DIB's color table
 * by finding the bits per pixel for the DIB (whether Win3.0 or other-style
 * DIB). If bits per pixel is 1: colors=2, if 4: colors=16, if 8: colors=256,
 * if 24, no colors in color table.
 *
 ************************************************************************/



WORD WINAPI DIBNumColors(LPSTR lpbi)
{
// static int counter=0;

	WORD wBitCount;  // DIB bit count

	/*  If this is a Windows-style DIB, the number of colors in the
	 *  color table can be less than the number of bits per pixel
	 *  allows for (i.e. lpbi->biClrUsed can be set to some value).
	 *  If this is the case, return the appropriate value.
	 */

	if (IS_WIN30_DIB(lpbi))
	{
		DWORD dwClrUsed;

		dwClrUsed = ((LPBITMAPINFOHEADER)lpbi)->biClrUsed;
		if (dwClrUsed != 0)
			return (WORD)dwClrUsed;
	}

	/*  Calculate the number of colors in the color table based on
	 *  the number of bits per pixel for the DIB.
	 */
	if (IS_WIN30_DIB(lpbi))
		wBitCount = ((LPBITMAPINFOHEADER)lpbi)->biBitCount;
	else
		wBitCount = ((LPBITMAPCOREHEADER)lpbi)->bcBitCount;

	/* return number of colors based on bits per pixel */
	switch (wBitCount)
	{
		case 1:
			return 2;

		case 4:
			return 16;

		case 8:
			return 256;

		default:
			return 0;
	}
}


//////////////////////////////////////////////////////////////////////////
//// Clipboard support

//---------------------------------------------------------------------
//
// Function:   CopyHandle (from SDK DibView sample clipbrd.c)
//
// Purpose:    Makes a copy of the given global memory block.  Returns
//             a handle to the new memory block (NULL on error).
//
//             Routine stolen verbatim out of ShowDIB.
//
// Parms:      h == Handle to global memory to duplicate.
//
// Returns:    Handle to new global memory block.
//
//---------------------------------------------------------------------

HGLOBAL WINAPI CopyHandle (HGLOBAL h)
{
	if (h == NULL)
		return NULL;

	DWORD dwLen = ::GlobalSize((HGLOBAL) h);
	HGLOBAL hCopy = ::GlobalAlloc(GHND, dwLen);

	if (hCopy != NULL)
	{
		void* lpCopy = ::GlobalLock((HGLOBAL) hCopy);
		void* lp     = ::GlobalLock((HGLOBAL) h);
		memcpy(lpCopy, lp, dwLen);
		::GlobalUnlock(hCopy);
		::GlobalUnlock(h);
	}

	return hCopy;
}