lfg.c

/*
 * LEAF Visual Novel System For X
 * (c) Copyright 1999,2000 Go Watanabe mailto:go@denpa.org
 * All rights reserverd.
 *
 * ORIGINAL LVNS (c) Copyright 1996-1999 LEAF/AQUAPLUS Inc.
 *
 * $Id: lfg.c,v 1.14 2000/05/10 17:32:23 go Exp $
 *
 */

/*
 * $Id: lfg.c,v 1.14 2000/05/10 17:32:23 go Exp $
 */
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include "lvnsimage.h"
#include "leafpack.h"

LvnsImage*
lvnsimage_load_lfg(const u_char *data, LvnsImage *over)
{
    LvnsImage  *img;
    u_char *work;            /* 作業領域 */
    size_t size;
    int width, height, xoffset, yoffset;

    /* check magic number 'LEAFCODE' */
    if (strncmp(data, "LEAFCODE", 8)){
	fprintf(stderr, "This file isn't LFG format.\n");
	return NULL;
    }

    /* geometry */
    xoffset = (data[33] << 8 | data[32]) * 8;
    yoffset =  data[35] << 8 | data[34];
    width   = ((data[37] << 8 | data[36]) + 1) * 8;
    height  = ((data[39] << 8 | data[38]) + 1);

    if (over) {
        /* XXX no check.... */
	img = over;
        img->width = width;
        img->height = height;
        img->xoffset = xoffset;
        img->yoffset = yoffset;
        img->rwidth  = width  - xoffset;
        img->rheight = height - yoffset;
    } else
        img = lvnsimage_new(width, height, xoffset, yoffset);

    img->palette_num = 16;
    /* read palette */
    {
        /*   4bit 単位
         *   RG BR GB RG BR ...
         */

        int i;
        const u_char *p = data + 8;
        u_char *q = (u_char*)img->palette;  /* R G B R G B R G B ... */
        int  upper, lower;

        for (i = 0; i < 24; i++) {
            upper = *p & 0xf0; upper |= upper >> 4;
            lower = *p++ & 0xf; lower |= lower << 4;
            *q++ = upper;
            *q++ = lower;
        }
    }

    /* transparent color */
    img->transparent = data[41];

    /* image size */
    size = data[44] | (data[45]<<8) | (data[46]<<16) | (data[47]<<24);
    if ((work = malloc(size * sizeof *work)) == NULL) {
        perror("lfg/extract_body:");
        exit(1);
    }

    /* 展開 */
    leafpack_lzs(data + 48, work, size);


    /* convert to indexed image */
    {
        int i;
        u_char *p = work;
        u_char *q = img->data;

        /* direction flag */
        int direction = data[40];

        if (!direction) {  /* VERTICAL */
            int x=0, y=0;
            for (i = 0; i < size; i++, p++) {
                
                q[img->rwidth * y + x]  = (*p & 0x80) >> 4 |
                                    (*p & 0x20) >> 3 |
                                    (*p & 0x08) >> 2 |
                                    (*p & 0x02) >> 1;
                q[img->rwidth * y + x + 1] = (*p & 0x40) >> 3 |
                                       (*p & 0x10) >> 2 |
                                       (*p & 0x04) >> 1 |
                                       (*p & 0x01);
                if (++y >= img->rheight) {
                    y = 0;
                    x += 2;
                }   
            }
        } else {	/* HORIZONTAL */
            for (i = 0; i < size; i++, p++) {
                *q++ = (*p & 0x80) >> 4 |
                       (*p & 0x20) >> 3 |
                       (*p & 0x08) >> 2 |
                       (*p & 0x02) >> 1;
                *q++ = (*p & 0x40) >> 3 |
                       (*p & 0x10) >> 2 |
                       (*p & 0x04) >> 1 |
                       (*p & 0x01);
            }
        }
    }

    /* 作業領域解放 */
    free(work);
    
    return img;
}

void
lvnsimage_load_lfg_palette(LvnsImage *img, const u_char *data)
{
    /* check magic number 'LEAFCODE' */
    if (strncmp(data, "LEAFCODE", 8)){
	fprintf(stderr, "This file isn't LFG format.\n");
	return;
    }

    img->palette_num = 16;
    /* read palette */
    {
        /*   4bit 単位
         *   RG BR GB RG BR ...
         */

        int i;
        const u_char *p = data + 8;
        u_char *q = (u_char*)img->palette;  /* R G B R G B R G B ... */
        int  upper, lower;

        for (i = 0; i < 24; i++) {
            upper = *p & 0xf0; upper |= upper >> 4;
            lower = *p++ & 0xf; lower |= lower << 4;
            *q++ = upper;
            *q++ = lower;
        }
    }

    /* transparent color */
    img->transparent = data[41];
}