home *** CD-ROM | disk | FTP | other *** search
- /****************************************************************************
- * iff.c
- *
- * This file implements a simple IFF format file reader.
- *
- * from Persistence of Vision Raytracer
- * Copyright 1993 Persistence of Vision Team
- *---------------------------------------------------------------------------
- * NOTICE: This source code file is provided so that users may experiment
- * with enhancements to POV-Ray and to port the software to platforms other
- * than those supported by the POV-Ray Team. There are strict rules under
- * which you are permitted to use this file. The rules are in the file
- * named POVLEGAL.DOC which should be distributed with this file. If
- * POVLEGAL.DOC is not available or for more info please contact the POV-Ray
- * Team Coordinator by leaving a message in CompuServe's Graphics Developer's
- * Forum. The latest version of POV-Ray may be found there as well.
- *
- * This program is based on the popular DKB raytracer version 2.12.
- * DKBTrace was originally written by David K. Buck.
- * DKBTrace Ver 2.0-2.12 were written by David K. Buck & Aaron A. Collins.
- *
- *****************************************************************************/
-
- #include "frame.h"
- #include "povproto.h"
-
- static IMAGE_COLOUR *iff_colour_map;
- static int colourmap_size;
- static CHUNK_HEADER Chunk_Header;
-
- #define FORM 0x464f524dL
- #define ILBM 0x494c424dL
- #define BMHD 0x424d4844L
- #define CAMG 0x43414d47L
- #define CMAP 0x434d4150L
- #define BODY 0x424f4459L
- #define CMPNONE 0
-
- #define HAM 0x800
-
- void iff_error()
- {
- fprintf (stderr, "Invalid IFF file\n");
- exit(1);
- }
-
- int read_byte(f)
- FILE *f;
- {
- int c;
- if ((c = getc(f)) == EOF)
- iff_error();
- return (c);
- }
-
- int read_word(f)
- FILE *f;
- {
- int result;
-
- result = read_byte(f)*256;
- result += read_byte(f);
- return (result);
- }
-
- long read_long(f)
- FILE *f;
- {
- int i;
- long result;
-
- result = 0;
- for (i = 0 ; i < 4 ; i++)
- result = result * 256 + read_byte(f);
-
- return (result);
- }
-
- void Read_Chunk_Header (f, dest)
- FILE *f;
- CHUNK_HEADER *dest;
- {
- dest->name = read_long(f);
- dest->size = read_long(f);
- }
-
- void Read_Iff_Image(Image, filename)
- IMAGE *Image;
- char *filename;
- {
- FILE *f;
- unsigned char **row_bytes;
- int c, i, j, k, nBytes, nPlanes, compression,
- mask, byte_index, count, viewmodes;
- int Previous_Red, Previous_Green, Previous_Blue;
- struct Image_Line *line;
- unsigned long creg;
-
- if ((f = Locate_File(filename, READ_FILE_STRING)) == NULL)
- {
- fprintf (stderr, "Cannot open IFF file %s\n", filename);
- exit(1);
- }
-
- Previous_Red = Previous_Green = Previous_Blue = 0;
-
- viewmodes = 0;
- iff_colour_map = NULL;
-
- while (1)
- {
- Read_Chunk_Header(f, &Chunk_Header);
- switch ( IFF_SWITCH_CAST Chunk_Header.name)
- {
- case FORM:
- if (read_long(f) != ILBM)
- iff_error();
- break;
-
- case BMHD:
- Image->iwidth = read_word(f);
- Image->width = (DBL)Image->iwidth;
- Image->iheight = read_word(f);
- Image->height = (DBL)Image->iheight;
-
- read_word(f); /* x position ignored */
- read_word(f); /* y position ignored */
- nPlanes = read_byte(f);
- colourmap_size = 1<<nPlanes;
- read_byte(f); /* masking ignored */
- compression = read_byte(f); /* masking ignored */
- read_byte(f); /* pad */
- read_word(f); /* Transparent colour ignored */
- read_word(f); /* Aspect ratio ignored */
- read_word(f); /* page width ignored */
- read_word(f); /* page height ignored */
- break;
-
- case CAMG:
- viewmodes = (int) read_long(f); /* Viewmodes */
- if (viewmodes & HAM)
- colourmap_size = 16;
-
- break;
-
- case CMAP:
- colourmap_size = (int) Chunk_Header.size / 3;
-
- if ((iff_colour_map = (IMAGE_COLOUR *) malloc(sizeof(IMAGE_COLOUR)*colourmap_size)) == NULL)
- {
- fprintf(stderr, "Cannot allocate memory for IFF colour map\n");
- exit(1);
- }
-
- for (i = 0 ; i < colourmap_size ; i++)
- {
- iff_colour_map[i].Red = read_byte(f);
- iff_colour_map[i].Green = read_byte(f);
- iff_colour_map[i].Blue = read_byte(f);
- iff_colour_map[i].Filter = 0;
- }
-
- Previous_Red = iff_colour_map[0].Red;
- Previous_Green = iff_colour_map[0].Green;
- Previous_Blue = iff_colour_map[0].Blue;
- for (i = colourmap_size * 3 ; (long) i < Chunk_Header.size ; i++)
- read_byte(f);
-
- break;
-
- case BODY:
- if ((iff_colour_map == NULL) || (viewmodes & HAM))
- {
- Image->Colour_Map_Size = 0;
- Image->Colour_Map = NULL;
- }
- else
- {
- Image->Colour_Map_Size = colourmap_size;
- Image->Colour_Map = iff_colour_map;
- }
-
- if ((row_bytes = (unsigned char **) malloc (4*nPlanes)) == NULL)
- {
- fprintf (stderr, "Cannot allocate memory for row bytes\n");
- exit(1);
- }
-
- for (i = 0 ; i < nPlanes ; i++)
- if ((row_bytes[i] = (unsigned char *)
- malloc(((Image->iwidth+15)/16)*2)) == NULL)
- {
- fprintf (stderr, "Cannot allocate memory for row bytes\n");
- exit(1);
- }
-
- if (Image->Colour_Map == NULL)
- {
- if ((Image->data.rgb_lines = (struct Image_Line *)
- malloc(Image->iheight * sizeof (struct Image_Line)))==NULL)
- {
- fprintf (stderr, "Cannot allocate memory for picture\n");
- exit(1);
- }
- }
- else
- {
- if ((Image->data.map_lines = (unsigned char **)
- malloc(Image->iheight * sizeof (unsigned char *)))==NULL)
- {
- fprintf (stderr, "Cannot allocate memory for picture\n");
- exit(1);
- }
- }
-
- for (i = 0 ; i < Image->iheight ; i++)
- {
-
- if (Image->Colour_Map == NULL)
- {
- if (((Image->data.rgb_lines[i].red = (unsigned char *)
- malloc(Image->iwidth))==NULL) ||
- ((Image->data.rgb_lines[i].green = (unsigned char *)
- malloc(Image->iwidth))==NULL) ||
- ((Image->data.rgb_lines[i].blue = (unsigned char *)
- malloc(Image->iwidth))==NULL))
- {
- fprintf (stderr, "Cannot allocate memory for picture\n");
- exit(1);
- }
- }
- else
- {
- if ((Image->data.map_lines[i] = (unsigned char *)
- malloc(Image->iwidth * sizeof(unsigned char))) == NULL)
- {
- fprintf (stderr, "Cannot allocate memory for picture\n");
- exit(1);
- }
- }
-
- for (j = 0 ; j < nPlanes ; j++)
- if (compression == CMPNONE)
- {
- for (k = 0 ; k < (((Image->iwidth+15)/16)*2) ; k++)
- row_bytes[j][k] = (unsigned char)read_byte(f);
- if ((k & 1) != 0)
- read_byte(f);
- }
-
- else
- {
- nBytes = 0;
- while (nBytes != ((Image->iwidth+15)/16)*2)
- {
- c = read_byte(f);
- if ((c >= 0) && (c <= 127))
- for (k = 0 ; k <= c ; k++)
- row_bytes[j][nBytes++] = (unsigned char)read_byte(f);
- else if ((c >= 129) && (c <= 255))
- {
- count = 257-c;
- c = read_byte(f);
- for (k = 0 ; k < count ; k++)
- row_bytes[j][nBytes++] = (unsigned char)c;
- }
- }
- }
-
- mask = 0x80;
- byte_index = 0;
- for (j = 0 ; j < Image->iwidth ; j++)
- {
- creg = 0;
- for (k = nPlanes-1 ; k >= 0 ; k--)
- if (row_bytes[k][byte_index] & mask)
- creg = creg*2 + 1;
- else
- creg *= 2;
-
-
- if (viewmodes & HAM)
- {
- line = &Image->data.rgb_lines[i];
- switch (creg >> 4)
- {
- case 0:
- Previous_Red = line->red[j] = (unsigned char)iff_colour_map[creg].Red;
- Previous_Green = line->green[j] = (unsigned char)iff_colour_map[creg].Green;
- Previous_Blue = line->blue[j] = (unsigned char)iff_colour_map[creg].Blue;
- break;
-
- case 1:
- line->red[j] = (unsigned char)Previous_Red;
- line->green[j] = (unsigned char)Previous_Green;
- line->blue[j] = (unsigned char)(((creg & 0xf)<<4) + (creg&0xf));
- Previous_Blue = (int) line->blue[j];
- break;
-
- case 2:
- line->red[j] = (unsigned char)(((creg & 0xf)<<4) + (creg&0xf));
- Previous_Red = (int) line->red[j];
- line->green[j] = (unsigned char)Previous_Green;
- line->blue[j] = (unsigned char)Previous_Blue;
- break;
-
- case 3:
- line->red[j] = (unsigned char)Previous_Red;
- line->green[j] = (unsigned char)(((creg & 0xf)<<4) + (creg&0xf));
- Previous_Green = (int) line->green[j];
- line->blue[j] = (unsigned char)Previous_Blue;
- break;
- }
- }
- else if (nPlanes == 24)
- {
- line = &Image->data.rgb_lines[i];
- line->red[j] = (unsigned char)((creg >> 16) & 0xFF);
- line->green[j] = (unsigned char)((creg >> 8) & 0xFF);
- line->blue[j] = (unsigned char)(creg & 0xFF);
- }
- else
- {
- if (creg > (unsigned long)Image->Colour_Map_Size)
- {
- fprintf (stderr, "Error - IFF Image Map Colour out of range\n");
- exit(1);
- }
- Image->data.map_lines[i][j] = (char)creg;
- }
-
- mask >>= 1;
- if (mask == 0)
- {
- mask = 0x80;
- byte_index++;
- }
- }
- }
-
- free (row_bytes);
- fclose (f);
- return;
-
- default:
- for (i = 0 ; (long) i < Chunk_Header.size ; i++)
- if (getc(f) == EOF)
- iff_error();
- break;
- }
- }
- }
-