source: trunk/src/testing/app/bitplay/libimg/pnmdisp.c @ 4

/******************************************************************************
 * SAGE - Scalable Adaptive Graphics Environment
 *
 * Copyright (C) 2004 Electronic Visualization Laboratory,
 * University of Illinois at Chicago
 *
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 *  * Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *  * Redistributions in binary form must reproduce the above
 *    copyright notice, this list of conditions and the following disclaimer
 *    in the documentation and/or other materials provided with the distribution.
 *  * Neither the name of the University of Illinois at Chicago nor
 *    the names of its contributors may be used to endorse or promote
 *    products derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 * Direct questions, comments etc about SAGE to http://www.evl.uic.edu/cavern/forum/
 *
 *****************************************************************************/

/*
 * Given a Sun raster file, return a DISPIMAGE
 * containing its raster data and with size <= (xsize, ysize).
 */

#include <stdio.h>
#include <stdlib.h>
/* #include "rasterfile.h" */
#include "imginfo.h"

extern int pnm_getint( FILE * );

IMG *
pnmmakedisp(filename)
    char *filename;
{
    register FILE *f;
    IMG *di = NULL;
    int maxpix = 0, pnmkind;
    int xsize, ysize;
    int y;
    int c;

    f = fopen(filename, "r");
    if(f == NULL) {
        fprintf(stderr, "%s: cannot open: ", filename);
        perror("");
        return NULL;
    }

    if(fgetc(f) != 'P')
        goto fail;

    pnmkind = fgetc(f);

    xsize = pnm_getint(f);
    ysize = pnm_getint(f);
    switch(pnmkind) {
    case '1': case '4':
        maxpix = 1;
        break;
    case '2': case '5': /* fall into ... */
    case '3': case '6':
        maxpix = pnm_getint(f);
        break;
    default:
        goto fail;
    }
    if(xsize <= 0 || ysize <= 0 || maxpix <= 0)
        goto fail;

    if(pnmkind >= '4') {
        /* Skip to end of line, after which the binary data should follow */
        while((c = fgetc(f)) != EOF && c != '\n')
            ;
    }

    di = (IMG *)malloc(sizeof(IMG));
    if(pnmkind == '1' || pnmkind == '4') {
        di->type = IT_BIT;
        di->rowbytes = (xsize+31)/32 * 4;
    } else {
        di->type = IT_LONG;
        di->rowbytes = xsize*4;
    }
    di->xsize = xsize;
    di->ysize = ysize;
    di->data = malloc(di->rowbytes * ysize);
    if(di->data == NULL) {
        fprintf(stderr, "Can't malloc %d bytes of memory for image\n",
            di->rowbytes*ysize);
        exit(2);
    }
    for(y = ysize; --y >= 0; ) {
        register int v;
        register long *rp;
        register int x;

        rp = (long *)(di->data + y*di->rowbytes);
        x = xsize;
        switch(pnmkind) {
        case '1':
            do {
                *rp++ = 0xff000000 | -pnm_getint(f);
            } while(--x > 0);
            break;
        case '2':
            do {
                v = (255 * pnm_getint(f) / maxpix);
                *rp++ = 0xff000000 | (v << 16) | (v<<8) | v;
            } while(--x > 0);
            break;
        case '3':
            do {
                v = (255 * pnm_getint(f) / maxpix);
                v |= (255 * pnm_getint(f) / maxpix) << 8;
                *rp++ = v | (255 * pnm_getint(f) / maxpix) << 16;
            } while(--x > 0);
            break;
        case '4':
            fread(rp, (xsize+7)/8, 1, f);       /* Bit mode */
            break;
        case '5':
            if(maxpix != 255) {
                do {
                    v = 255 * getc(f) / maxpix;
                    *rp++ = 0xff000000 | (v << 16) | (v << 8) | v;
                } while(--x > 0);
            } else {
                do {
                    v = getc(f);
                    *rp++ = 0xff000000 | (v << 16) | (v << 8) | v;
                } while(--x > 0);
            }
            break;
        case '6':
            if(maxpix != 255) {
                do {
                    v = 255 * getc(f) / maxpix;
                    v |= (255 * getc(f) / maxpix) << 8;
                    *rp++ = 0xff000000 | ((255 * getc(f) / maxpix) << 16) | v;
                } while(--x > 0);
            } else {
                do {
                    v = getc(f);
                    v |= getc(f) << 8;
                    *rp++ = 0xff000000 | (getc(f) << 16) | v;
                } while(--x > 0);
            }
            break;
        }
    }

    if(f != NULL)
        fclose(f);
    return di;

  fail:
    if(di) {
        if(di->data) free(di->data);
        free(di);
    }
    if(f != NULL)
        fclose(f);
    return NULL;
}