HPAVC/HPAVC CD-ROM.iso/IFF2PBM.ZIP/ACKIFF.C

C/C++ Source or Header | 1994-01-10 | 5KB | 191 lines

/******************* ( Animation Construction Kit 3D ) ***********************/
/*            Deluxe Paint file reader                 */
/* CopyRight (c) 1993  Authors: Jaimi McEntire, Lary Myers             */
/*****************************************************************************/
//
// This function will return a pointer to a buffer that holds the raw image.
// just free the pointer to delete this buffer. After returning, the array
// colordat will hold the adjusted palette of this pic.
//
// Also, this has been modified to only read in form PBM brushes. form ILBM's
// (the "old" type) are not supported. use the "new" deluxe paint .lbm type
// and do not choose "old".

#include <stdio.h>
#include <conio.h>
#include <process.h>
#include <bios.h>
#include <fcntl.h>
#include <malloc.h>
#include <mem.h>
#include "ack3d.h"
#include "ackeng.h"
#include "ackext.h"
#include "ackiff.h"


unsigned char far  colordat[768];   /* maximum it can be...256 colors    */

unsigned char far  cplanes[8][80];  /* setting max at 640 pixels width   */
                                    /* thats 8 pixels per byte per plane */
unsigned char far  *pplanes= (char far *) &cplanes[0][0];  /* for a form pbm */

int ErrorCode = 0;

unsigned char far * AckReadIff(char *picname)
   {
   FILE *pic;
   form_chunk    fchunk;
   ChunkHeader    chunk;
   BitMapHeader bmhd;
   long length;
   char value;       // must remain signed, no matter what. ignore any warnings.
   int sofar;
   int width,height,planes;
   int pixw;
   unsigned char far *destx, *savedestx;

   if ((pic = fopen(picname,"r+b"))== NULL)
    {
    ErrorCode = ERR_BADPICNAME;
    return(0L);
    }

   fread(&fchunk,1,sizeof(form_chunk),pic); /* read in the first 12 bytes*/

   if (fchunk.type != FORM)
      {
      fclose(pic);
      ErrorCode = ERR_INVALIDFORM;
      return(0L);
      }

   if (fchunk.subtype != ID_PBM)
      {
      printf("Error: Not form PBM!");
      fclose(pic);
      ErrorCode = ERR_NOPBM;
      return(0L);
      }
   // now lets loop...Because the Chunks can be in any order!
   while(1)
      {
      fread(&chunk,1,sizeof(ChunkHeader),pic);
      ByteFlipLong(&(long)(chunk.ckSize));
      if (chunk.ckSize & 1) chunk.ckSize ++;    // must be word aligned
      if(chunk.ckID == ID_BMHD)
      {
      fread(&bmhd,1,sizeof(BitMapHeader),pic);
      bmhd.w=swab(bmhd.w);            // the only things we need.
      bmhd.h=swab(bmhd.h);
      destx = (unsigned char far *)malloc((bmhd.w * bmhd.h)+4);
      if ( !destx )
        {
        fclose(pic);
        ErrorCode = ERR_NOMEMORY;
        return(0L);
        }

      savedestx = destx;

      destx[0] = bmhd.w%256;
      destx[1] = bmhd.w/256;
      destx[2] = bmhd.h%256;
      destx[3] = bmhd.h/256;
      destx += 4;
      continue;
      }
      if(chunk.ckID == ID_CMAP)
      {
      int i;
      unsigned char r,g;

      fread(colordat,1,chunk.ckSize,pic);
      for (i=0;i<768;i++)
          {
           r = colordat[i];      // r,g do not stand for red and green
          g = r >> 2;
          colordat[i] = g;
          }
      continue;
      }
      if(chunk.ckID == ID_BODY)
      {
      for(height = 0; height<bmhd.h; height ++)
         {
         unsigned char *dest;
         dest = (unsigned char *)&(pplanes[0]); /* point at first char  */
         sofar = bmhd.w;                /* number of bytes = 8  */
         if (sofar&1) sofar++;
         while (sofar)
        {
        if (bmhd.compression)
           {
           value=fgetc(pic);      /* get the next byte      */
           // if (value == 128) continue; /* NOP..just get another*/
           if (value > 0)
              {
              int len;
              len = value +1;
              sofar -= len;
              if(!(fread(dest,len,1,pic)))
              {
              fclose(pic);
              ErrorCode = ERR_BADPICFILE;
              free(savedestx);
              return(0L);
              }
              dest +=len;
              }
           else
              {
              int count;
              count = -value; /* get amount to dup */
              count ++;
              sofar -= count;
              value=fgetc(pic);
              while (--count >= 0) *dest++ = value;
              }
           }
        else
           {
           fread(dest,sofar,1,pic); /* just throw on plane */
           sofar = 0;
           }
        }
         if (sofar < 0)
        {
        fclose(pic);
        }
         _fmemcpy(destx,pplanes,bmhd.w);
         destx += bmhd.w;
         }
      break; /* leave if we've unpacked the BODY*/
      }
      fseek(pic,chunk.ckSize,SEEK_CUR);
      }

   fclose(pic);
   return((char far *)savedestx);
   }

void ByteFlipLong(long *NUMBER)
   {
   // Hey, I didn;t write this function!!!
   long int Y, T;
   int I;

   T = *NUMBER;
   Y=0;for (I=0;I<4;I++){Y = Y | (T & 0xFF);if (I<3) {Y = Y << 8;T = T >> 8;}}
   *NUMBER = Y;
   }

int swab(unsigned short number)
   {
   unsigned int xx1,xx2;
   unsigned int result;

   xx1 = number <<8; xx2 = number >>8; result = xx1|xx2;
   return(result);
   }