Amiga ISO Collection/AmigaUtilCD2.iso/Programming/Misc/TRSICAT.LZX/CATS_CD2_TRSI/Reference_Library/Devices/modules/loadilbm.c

C/C++ Source or Header | 1992-08-21 | 5.0 KB | 209 lines

/* loadilbm.c 05/91  C. Scheppner CBM
 *
 * High-level ILBM load routines
 */

#include "iffp/ilbm.h"
#include "iffp/ilbmapp.h"

extern struct Library *GfxBase;

/* loadbrush
 *
 * Passed an initialized ILBMInfo with a not-in-use ParseInfo.iff
 *   IFFHandle and desired propchks, collectchks, and stopchks, and filename,
 *   will load an ILBM as a brush, setting up ilbm->Bmhd, ilbm->camg,
 *   ilbm->brbitmap, ilbm->colortable, and ilbm->ncolors
 *
 *   Note that ncolors may be more colors than you can LoadRGB4.
 *   Use MIN(ilbm->ncolors,MAXAMCOLORREG) for color count if you change
 *   the colors yourself using 1.3/2.0 functions.
 *
 * Returns 0 for success or an IFFERR (libraries/iffparse.h)
 */

LONG loadbrush(struct ILBMInfo *ilbm, UBYTE *filename)
{
LONG error = 0L;

    if(!(ilbm->ParseInfo.iff))    return(CLIENT_ERROR);

    if(!(error = openifile((struct ParseInfo *)ilbm, filename, IFFF_READ)))
    {
    error = parseifile((struct ParseInfo *)ilbm,
                ID_FORM, ID_ILBM,
                ilbm->ParseInfo.propchks,
                ilbm->ParseInfo.collectchks,
                ilbm->ParseInfo.stopchks);
    if((!error)||(error == IFFERR_EOC)||(error == IFFERR_EOF))
        {
        if(contextis(ilbm->ParseInfo.iff,ID_ILBM,ID_FORM))
        {
            if(error = createbrush(ilbm))   deletebrush(ilbm);
        }
        else
        {
        closeifile((struct ParseInfo *)ilbm);
        message("Not an ILBM\n");
        error = NOFILE;
        }
        }
    }
    return(error);
}


/* unloadbrush
 *
 * frees and close everything alloc'd/opened by loadbrush
 */
void unloadbrush(struct ILBMInfo *ilbm)
{
    closeifile((struct ParseInfo *)ilbm);
    deletebrush(ilbm);
}


/* queryilbm
 *
 * Passed an initilized ILBMInfo with a not-in-use IFFHandle,
 *   and a filename,
 *   will open an ILBM, fill in ilbm->camg and ilbm->bmhd,
 *   and close the ILBM.
 *
 * This allows you to determine if the ILBM is a size and
 *   type you want to deal with.
 *
 * Returns 0 for success or an IFFERR (libraries/iffparse.h)
 */

/* query just wants these chunks */
LONG queryprops[] = { ID_ILBM, ID_BMHD,
              ID_ILBM, ID_CAMG,
                      TAG_DONE };

/* scan can stop when a CMAP or BODY is reached */
LONG querystops[] = { ID_ILBM, ID_CMAP,
              ID_ILBM, ID_BODY,
              TAG_DONE };

LONG queryilbm(struct ILBMInfo *ilbm, UBYTE *filename)
{
LONG error = 0L;
BitMapHeader *bmhd;

    if(!(ilbm->ParseInfo.iff))    return(CLIENT_ERROR);

    if(!(error = openifile((struct ParseInfo *)ilbm, filename, IFFF_READ)))
    {
    D(bug("queryilbm: openifile successful\n"));

    error = parseifile((struct ParseInfo *)ilbm,
            ID_FORM, ID_ILBM,
            queryprops, NULL, querystops);

    D(bug("queryilbm: after parseifile, error = %ld\n",error));

    if((!error)||(error == IFFERR_EOC)||(error == IFFERR_EOF))
        {
        if(contextis(ilbm->ParseInfo.iff,ID_ILBM,ID_FORM))
        {
        if(bmhd = (BitMapHeader*)
            findpropdata(ilbm->ParseInfo.iff,ID_ILBM,ID_BMHD))
            {
            *(&ilbm->Bmhd) = *bmhd;
            ilbm->camg = getcamg(ilbm);
            }
        else error = NOFILE;
        }
        else
        {
        message("Not an ILBM\n");
        error = NOFILE;
        }
        }
    closeifile(ilbm);
    }
    return(error);
}


/* loadilbm
 *
 * Passed a not-in-use IFFHandle, an initialized ILBMInfo, and filename,
 *   will load an ILBM into your already opened ilbm->scr, setting up
 *   ilbm->Bmhd, ilbm->camg, ilbm->colortable, and ilbm->ncolors
 *   and loading the colors into the screen's viewport
 *
 *   Note that ncolors may be more colors than you can LoadRGB4.
 *   Use MIN(ilbm->ncolors,MAXAMCOLORREG) for color count if you change
 *   the colors yourself using 1.3/2.0 functions.
 *
 * Returns 0 for success or an IFFERR (libraries/iffparse.h)
 *
 * NOTE - loadilbm() keeps the IFFHandle open so you can copy
 *   or examine other chunks.  You must call closeifile(iff,ilbm)
 *   to close the file and deallocate the parsed context
 *
 */

LONG loadilbm(struct ILBMInfo *ilbm, UBYTE *filename)
{
LONG error = 0L;


    D(bug("loadilbm:\n"));

    if(!(ilbm->ParseInfo.iff))    return(CLIENT_ERROR);
    if(!ilbm->scr)        return(CLIENT_ERROR);

    if(!(error = openifile((struct ParseInfo *)ilbm, filename, IFFF_READ)))
    {
    D(bug("loadilbm: openifile successful\n"));

    error = parseifile((struct ParseInfo *)ilbm,
            ID_FORM, ID_ILBM,
            ilbm->ParseInfo.propchks,
            ilbm->ParseInfo.collectchks,
            ilbm->ParseInfo.stopchks);

    D(bug("loadilbm: after parseifile, error = %ld\n",error));

    if((!error)||(error == IFFERR_EOC)||(error == IFFERR_EOF))
        {
        if(contextis(ilbm->ParseInfo.iff,ID_ILBM,ID_FORM))
        {
            error = loadbody(ilbm->ParseInfo.iff,
                    &ilbm->scr->BitMap, &ilbm->Bmhd);

        D(bug("loadilbm: after loadbody, error = %ld\n",error));

        if(!error)
            {
            if(!(getcolors(ilbm)))
                LoadRGB4(&ilbm->scr->ViewPort,ilbm->colortable,
                    MIN(ilbm->ncolors,MAXAMCOLORREG));
            }
        }
        else
        {
        closeifile((struct ParseInfo *)ilbm);
        message("Not an ILBM\n");
        error = NOFILE;
        }
        }
    }
    return(error);
}


/* unloadilbm
 *
 * frees and closes everything allocated by loadilbm
 */
void unloadilbm(struct ILBMInfo *ilbm)
{
    closeifile((struct ParseInfo *)ilbm);
    freecolors(ilbm);
}