/* * 2ooM: The Master of Orion II Reverse Engineering Project * Library for working with LBX image files. * Copyright © 2006-2011, 2013 Nick Bowler * * This program is free software: you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation, either version 3 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program. If not, see . */ #include #include #include #include #include #include "pack.h" #include "misc.h" #include "lbx.h" #include "error.h" #include "image.h" #define FLAG_RAW 0x0100 /* Image is stored as a flat array of bytes. */ #define FLAG_OVERWRITE 0x0400 /* Draw each frame on a clean slate (unsure). */ #define FLAG_BUILDING 0x0800 /* Buildings have this, related to shadow? */ #define FLAG_PALETTE 0x1000 /* Image contains embedded palette. */ #define FLAG_LOOPING 0x2000 /* Loop over all frames in the image (unsure). */ #define FLAG_ALL (FLAG_RAW|FLAG_OVERWRITE|FLAG_BUILDING|FLAG_PALETTE|FLAG_LOOPING) #define HDR_LEN 12 struct lbx_image_priv { struct lbx_image pub; unsigned short wtf, flags; unsigned char wtf2, leadin; unsigned short palstart, palcount; const struct lbx_file_ops *fops; int (*dtor)(void *handle); void *f; long paloff; int currentframe; int currentx, currenty; unsigned char **framedata; unsigned char **mask; unsigned long offsets[]; }; static struct lbx_image_priv *lbx_img_init(unsigned char hdr[static HDR_LEN]) { unsigned short nframes = unpack_16_le(hdr+6); struct lbx_image_priv *img; img = malloc(sizeof *img + sizeof img->offsets[0] * (nframes+1)); if (!img) { lbx_error_raise(LBX_ENOMEM); return NULL; } *img = (struct lbx_image_priv) { .pub.width = unpack_16_le(hdr+0), .pub.height = unpack_16_le(hdr+2), .wtf = unpack_16_le(hdr+4), .pub.frames = hdr[6], .wtf2 = hdr[7], .leadin = hdr[8], .pub.chunk = hdr[9], .flags = unpack_16_le(hdr+10), .currentframe = -1, }; return img; } struct lbx_image *lbx_img_open(void *f, const struct lbx_file_ops *fops, int (*destructor)(void *)) { unsigned char hdr_buf[HDR_LEN]; struct lbx_image_priv *img; if (fops->read(hdr_buf, sizeof hdr_buf, f) != sizeof hdr_buf) { if (fops->eof(f)) lbx_error_raise(LBX_EEOF); return NULL; } img = lbx_img_init(hdr_buf); if (!img) return NULL; img->f = f; img->fops = fops; img->dtor = destructor; /* * DEBUG ONLY. These assertions exist to catch otherwise valid image * files which differ from what I believe to be true of all LBX images. * When we can decode every image, then these assertions should be * replaced with constraints. */ _lbx_assert(img->wtf == 0); /* version? */ _lbx_assert(img->wtf2 == 0); /* very likely is simply reserved. */ _lbx_assert(img->pub.frames > img->leadin); _lbx_assert(!(img->flags & ~FLAG_ALL)); /* Read all offsets. Should be merged with identical code in lbx.c */ for (unsigned i = 0; i <= img->pub.frames; i++) { unsigned char buf[4]; if (fops->read(buf, sizeof buf, f) != sizeof buf) { if (fops->eof(f)) lbx_error_raise(LBX_EEOF); free(img); return NULL; } img->offsets[i] = unpack_32_le(buf); } if (img->flags & FLAG_PALETTE) { unsigned char buf[4]; if (fops->read(buf, sizeof buf, f) != sizeof buf) { if (fops->eof(f)) lbx_error_raise(LBX_EEOF); free(img); return NULL; } img->palstart = unpack_16_le(buf+0); img->palcount = unpack_16_le(buf+2); img->paloff = fops->tell(f); if (img->palstart + img->palcount > 256) { lbx_error_raise(LBX_EFORMAT); free(img); return NULL; } } return &img->pub; } static int pipe_close(void *f) { struct lbx_pipe_state *p = f; int rc; rc = fclose(p->f); free(p); return rc; } static int file_close(void *f) { return fclose((FILE *)f); } struct lbx_image *lbx_img_fopen(const char *file) { struct lbx_pipe_state *p; FILE *f; f = fopen(file, "rb"); if (!f) { lbx_error_raise(-errno); return NULL; } if (fseek(f, 0, SEEK_CUR) == 0) return lbx_img_open(f, &lbx_default_fops, file_close); p = malloc(sizeof *p); if (!p) { lbx_error_raise(LBX_ENOMEM); fclose(f); return NULL; } *p = (struct lbx_pipe_state) { .f = f }; return lbx_img_open(p, &lbx_pipe_fops, pipe_close); } static int _lbx_drawrow(int first, struct lbx_image_priv *img) { unsigned short type, count, yval, xval; unsigned char buf[4]; unsigned char *pos; size_t rc; assert(img->framedata); assert(img->mask); if (img->fops->read(buf, sizeof buf, img->f) != sizeof buf) goto readerr; type = unpack_16_le(buf+0); if (first) { img->currentx = 0; img->currenty = 0; type = 0; } if (type == 0) { yval = unpack_16_le(buf+2); if (yval == 1000) return 1; if (img->fops->read(buf, sizeof buf, img->f) != sizeof buf) goto readerr; count = unpack_16_le(buf+0); xval = unpack_16_le(buf+2); if (xval == 1000) return 1; /* Ensure that the row fits in the image. */ if (img->pub.height - img->currenty <= yval || xval >= img->pub.width) { lbx_error_raise(LBX_EFORMAT); return -1; } img->currenty += yval; img->currentx = xval; } else { xval = unpack_16_le(buf+2); if (img->pub.width - img->currentx <= xval) { lbx_error_raise(LBX_EFORMAT); return -1; } img->currentx += xval; count = type; } if (count > img->pub.width - img->currentx) { lbx_error_raise(LBX_EFORMAT); return -1; } memset(&img->mask[img->currenty][img->currentx], 1, count); pos = &img->framedata[img->currenty][img->currentx]; rc = img->fops->read(pos, count, img->f); img->currentx += rc; if (rc < count) goto readerr; if (count % 2) { if (img->fops->read(buf, 1, img->f) != 1) goto readerr; } return 0; readerr: if (img->fops->eof(img->f)) lbx_error_raise(LBX_EEOF); return -1; } static unsigned char **allocframebuffer(size_t width, size_t height) { unsigned char **new, *tmp; size_t i; tmp = calloc(height, width); if (!tmp) { lbx_error_raise(LBX_ENOMEM); return NULL; } new = malloc(height * sizeof *new); if (!new) { lbx_error_raise(LBX_ENOMEM); free(tmp); return NULL; } for (i = 0; i < height; i++) { new[i] = tmp + i * width; } return new; } static unsigned char **read_raw_frame(struct lbx_image_priv *img, int frame) { unsigned long size = img->pub.width * img->pub.height; assert(img->flags & FLAG_RAW); if (img->fops->seek(img->f, img->offsets[frame], SEEK_SET)) { return NULL; } if (img->fops->read(img->framedata[0], size, img->f) != size) { if (img->fops->eof(img->f)) lbx_error_raise(LBX_EEOF); return NULL; } memset(img->mask[0], 1, size); if (img->fops->tell(img->f) > img->offsets[frame+1]) { lbx_error_raise(LBX_EFORMAT); return NULL; } return img->framedata; } unsigned char **lbx_img_getframe(struct lbx_image *pub, int frame) { struct lbx_image_priv *img = (struct lbx_image_priv *)pub; if (frame >= pub->frames || frame < 0) { lbx_error_raise(LBX_ENOENT); return NULL; } if (!img->framedata) { img->framedata = allocframebuffer(pub->width, pub->height); if (!img->framedata) return NULL; } if (!img->mask) { img->mask = allocframebuffer(pub->width, pub->height); if (!img->mask) return NULL; } if (img->flags & FLAG_RAW) return read_raw_frame(img, frame); if ((img->flags & FLAG_OVERWRITE) || (pub->chunk && !(frame % pub->chunk))) { /* Clear the slate. */ img->currentframe = -1; memset(img->framedata[0], 0, pub->width * pub->height); memset(img->mask[0], 0, pub->width * pub->height); } else { /* Start over if we are backtracking. */ if (img->currentframe > frame) { memset(img->mask[0], 0, pub->width * pub->height); img->currentframe = -1; } /* We must have previous frame decoded to continue. */ if (frame > img->currentframe + 1) { if (!lbx_img_getframe(pub, frame-1)) return NULL; } } if (img->currentframe != frame) { int rc, first = 1; if (img->fops->seek(img->f, img->offsets[frame], SEEK_SET)) { return NULL; } do { rc = _lbx_drawrow(first, img); if (rc == -1) return NULL; first = 0; if (img->fops->tell(img->f) > img->offsets[frame+1]) { lbx_error_raise(LBX_EFORMAT); return NULL; } } while (!rc); } img->currentframe = frame; return img->framedata; } int lbx_img_loadpalette(void *f, const struct lbx_file_ops *fops, struct lbx_colour palette[static 256]) { unsigned char entry[4]; int i; for (i = 0; i < 256; i++) { if (fops->read(entry, sizeof entry, f) != sizeof entry) { if (fops->eof(f)) lbx_error_raise(LBX_EEOF); return -1; } if (entry[0] != 1) { lbx_error_raise(LBX_EFORMAT); return -1; } palette[i] = (struct lbx_colour) { .red = entry[1] & 0x3f, .green = entry[2] & 0x3f, .blue = entry[3] & 0x3f, .active = 1, }; } return 0; } int lbx_img_getpalette(struct lbx_image *pub, struct lbx_colour palette[static 256]) { struct lbx_image_priv *img = (struct lbx_image_priv *)pub; unsigned char entry[4]; unsigned int i; size_t rc; /* Do nothing if the image doesn't have embedded palette data. */ if (!(img->flags & FLAG_PALETTE)) return 0; if (img->fops->seek(img->f, img->paloff, SEEK_SET)) { return -1; } for (i = 0; i < img->palcount; i++) { rc = img->fops->read(entry, sizeof entry, img->f); if (rc < sizeof entry) { goto readerr; } if (entry[0] != 0) { lbx_error_raise(LBX_EFORMAT); return -1; } palette[img->palstart + i] = (struct lbx_colour){ .red = entry[1], .green = entry[2], .blue = entry[3], .active = 1, }; } return 0; readerr: if (img->fops->eof(img->f)) lbx_error_raise(LBX_EEOF); return -1; } void lbx_img_getinfo(struct lbx_image *pub, struct lbx_imginfo *info) { struct lbx_image_priv *img = (struct lbx_image_priv *)pub; *info = (struct lbx_imginfo) { .palettesz = (img->flags & FLAG_PALETTE) ? img->palcount : 0, }; /* There seems to be two ways of specifying that an image loops. */ if (img->flags & FLAG_LOOPING) { info->loopstart = 0; info->looping = 1; } else if (img->leadin != pub->frames - 1) { info->loopstart = img->leadin; info->looping = 1; } } unsigned char **lbx_img_getmask(struct lbx_image *pub) { struct lbx_image_priv *img = (struct lbx_image_priv *)pub; return img->mask; } int lbx_img_close(struct lbx_image *pub) { struct lbx_image_priv *img = (struct lbx_image_priv *)pub; int rc = 0; if (img) { if (img->framedata) { free(img->framedata[0]); free(img->framedata); } if (img->mask) { free(img->mask[0]); free(img->mask); } if (img && img->dtor) { rc = img->dtor(img->f); } free(img); } return rc; }