]> git.draconx.ca Git - liblbx.git/blobdiff - src/image.c
liblbx: Add support for "chunked" images.
[liblbx.git] / src / image.c
index 81f66e015e6e05e602dfca397d78901f7355d959..5f3a6e320c51f62010d12f24ac8fac28a0d9bd63 100644 (file)
+/*
+ *  2ooM: The Master of Orion II Reverse Engineering Project
+ *  Library for working with LBX image files.
+ *  Copyright (C) 2006-2008 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 <http://www.gnu.org/licenses/>.
+ */
 #ifdef HAVE_CONFIG_H
 #      include "config.h"
 #endif
 
 #include <stdlib.h>
-#include <stdint.h>
+#include <string.h>
 #include <assert.h>
 #include <errno.h>
 
-#include "byteorder.h"
+#include "pack.h"
 #include "misc.h"
 #include "lbx.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 {
-       uint16_t width, height;
-       uint16_t wtf1, wtf2;
-       uint16_t offs, frames;
+       unsigned short width, height;
+       unsigned short wtf, flags;
+       unsigned char  frames, wtf2, leadin, chunk;
+       unsigned short palstart, palcount;
+
+       const struct lbx_file_ops *fops;
+       int (*dtor)(void *handle);
+       void *f;
 
-       FILE *f;
-       long foff;
+       long paloff;
 
        int currentframe;
        int currentx, currenty;
        unsigned char **framedata;
+       unsigned char **mask;
 
-       uint32_t offsets[];
+       unsigned long offsets[];
 };
 
-struct lbx_image *lbximg_fopen(FILE *f)
+static struct lbx_image *lbximg_init(unsigned char hdr[static HDR_LEN])
+{
+       unsigned short nframes = unpack_16_le(hdr+6);
+       struct lbx_image *img;
+
+       img = malloc(sizeof *img + sizeof img->offsets[0] * (nframes+1));
+       if (!img) {
+               lbx_errno = -errno;
+               return NULL;
+       }
+
+       *img = (struct lbx_image) {
+               .width  = unpack_16_le(hdr+0),
+               .height = unpack_16_le(hdr+2),
+               .wtf    = unpack_16_le(hdr+4),
+               .frames = hdr[6],
+               .wtf2   = hdr[7],
+               .leadin = hdr[8],
+               .chunk  = hdr[9],
+               .flags  = unpack_16_le(hdr+10),
+
+               .currentframe = -1,
+       };
+
+       return img;
+}
+
+struct lbx_image *lbximg_open(void *f, const struct lbx_file_ops *fops,
+                              int (*destructor)(void *))
 {
-       struct lbx_image tmp = {.f = f}, *new;
-
-       if (fread(&tmp.width,  sizeof tmp.width,   1, f) != 1) goto readerr;
-       if (fread(&tmp.height, sizeof tmp.height,  1, f) != 1) goto readerr;
-       if (fread(&tmp.wtf1,   sizeof tmp.wtf1,    1, f) != 1) goto readerr;
-       if (fread(&tmp.offs,   sizeof tmp.offs,    1, f) != 1) goto readerr;
-       if (fread(&tmp.frames, sizeof tmp.frames,  1, f) != 1) goto readerr;
-       if (fread(&tmp.wtf2,   sizeof tmp.wtf2,    1, f) != 1) goto readerr;
-
-       tmp.width  = letohs(tmp.width);  tmp.foff += sizeof tmp.width;
-       tmp.height = letohs(tmp.height); tmp.foff += sizeof tmp.height;
-       tmp.wtf1   = letohs(tmp.wtf1);   tmp.foff += sizeof tmp.wtf1;
-       tmp.offs   = letohs(tmp.offs);   tmp.foff += sizeof tmp.offs;
-       tmp.frames = letohs(tmp.frames); tmp.foff += sizeof tmp.frames;
-       tmp.wtf2   = letohs(tmp.wtf2);   tmp.foff += sizeof tmp.wtf2;
+       unsigned char hdr_buf[HDR_LEN];
+       struct lbx_image *img;
+
+       if (fops->read(hdr_buf, sizeof hdr_buf, f) != sizeof hdr_buf) {
+               lbx_errno = -errno;
+               if (fops->eof(f))
+                       lbx_errno = LBX_EEOF;
+               return NULL;
+       }
+
+       img = lbximg_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.
-        * If we never find any exceptions, we can replace the assertions with
-        * assumptions.
+        * When we can decode every image, then these assertions should be
+        * replaced with constraints.
         */
-       _lbx_assert(tmp.wtf1 == 0);
-       _lbx_assert(tmp.offs == tmp.frames + 1);
+       _lbx_assert(img->wtf  == 0); /* version? */
+       _lbx_assert(img->wtf2 == 0); /* very likely is simply reserved. */
+       _lbx_assert(img->frames > img->leadin);
+       _lbx_assert(!(img->flags & ~FLAG_ALL));
 
-       new = malloc(sizeof *new + tmp.offs * sizeof *new->offsets);
-       if (!new) {
-               lbx_errno = -errno;
-               return NULL;
+       /* Read all offsets.  Should be merged with identical code in lbx.c */
+       for (unsigned i = 0; i <= img->frames; i++) {
+               unsigned char buf[4];
+
+               if (fops->read(buf, sizeof buf, f) != sizeof buf) {
+                       lbx_errno = -errno;
+                       if (fops->eof(f))
+                               lbx_errno = LBX_EEOF;
+                       free(img);
+                       return NULL;
+               }
+
+               img->offsets[i] = unpack_32_le(buf);
        }
 
-       *new = tmp;
-       new->currentframe = -1;
+       if (img->flags & FLAG_PALETTE) {
+               unsigned char buf[4];
 
-       if (fread(new->offsets, sizeof *new->offsets, new->offs, f)!= new->offs)
-               goto readerr;
-       new->foff += sizeof *new->offsets * new->offs;
+               if (fops->read(buf, sizeof buf, f) != sizeof buf) {
+                       lbx_errno = -errno;
+                       if (fops->eof(f))
+                               lbx_errno = LBX_EEOF;
+                       free(img);
+                       return NULL;
+               }
 
-       return new;
-readerr:
-       if (feof(f)) {
-               lbx_errno = LBX_EEOF;
-       } else {
-               lbx_errno = -errno;
+               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_errno = LBX_EFORMAT;
+                       free(img);
+                       return NULL;
+               }
        }
 
-       free(new);
-       return NULL;
+       return img;
+}
+
+struct lbx_image *lbximg_fopen(FILE *f)
+{
+       return lbximg_open(f, &lbx_default_fops, NULL);
 }
 
 static int _lbx_drawrow(int first, struct lbx_image *img)
 {
-       uint16_t type, yval, count, xval;
+       unsigned short type, count, yval, xval;
+       unsigned char buf[4];
        unsigned char *pos;
-       unsigned char abyss;
        size_t rc;
 
        assert(img->framedata);
+       assert(img->mask);
 
-       if (fread(&type, sizeof type, 1, img->f) != 1) goto readerr;
-       type = letohs(type); img->foff += sizeof type;
+       if (img->fops->read(buf, sizeof buf, img->f) != sizeof buf)
+               goto readerr;
+       type = unpack_16_le(buf+0);
 
        if (first) {
                img->currentx = 0;
@@ -98,16 +185,17 @@ static int _lbx_drawrow(int first, struct lbx_image *img)
        }
 
        if (type == 0) {
-               if (fread(&yval,  sizeof yval,  1, img->f) != 1) goto readerr;
-               yval = letohs(yval); img->foff += sizeof yval;
-
+               yval = unpack_16_le(buf+2);
                if (yval == 1000)
                        return 1;
 
-               if (fread(&count, sizeof count, 1, img->f) != 1) goto readerr;
-               count = letohs(count); img->foff += sizeof count;
-               if (fread(&xval,  sizeof xval,  1, img->f) != 1) goto readerr;
-               xval = letohs(xval); img->foff += sizeof xval;
+               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->height - img->currenty <= yval || xval >= img->width) {
@@ -118,8 +206,7 @@ static int _lbx_drawrow(int first, struct lbx_image *img)
                img->currenty += yval;
                img->currentx  = xval;
        } else {
-               if (fread(&xval,  sizeof xval,  1, img->f) != 1) goto readerr;
-               xval = letohs(xval); img->foff += sizeof xval;
+               xval = unpack_16_le(buf+2);
 
                if (img->width - img->currentx <= xval) {
                        lbx_errno = LBX_EFORMAT;
@@ -128,7 +215,6 @@ static int _lbx_drawrow(int first, struct lbx_image *img)
                img->currentx += xval;
 
                count = type;
-
        }
 
        if (count > img->width - img->currentx) {
@@ -136,28 +222,78 @@ static int _lbx_drawrow(int first, struct lbx_image *img)
                return -1;
        }
 
+       memset(&img->mask[img->currenty][img->currentx], 1, count);
+
        pos = &img->framedata[img->currenty][img->currentx];
-       rc  = fread(pos, 1, count, img->f);
+       rc  = img->fops->read(pos, count, img->f);
        img->currentx += rc;
-       img->foff     += rc;
 
        if (rc < count)
                goto readerr;
 
        if (count % 2) {
-               if (fread(&abyss, 1, 1, img->f) != 1)
+               if (img->fops->read(buf, 1, img->f) != 1)
                        goto readerr;
-               img->foff += 1;
        }
 
        return 0;
 readerr:
-       if (feof(img->f)) {
+       lbx_errno = -errno;
+       if (img->fops->eof(img->f))
                lbx_errno = LBX_EEOF;
-       } else {
+       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_errno = -errno;
+               return NULL;
        }
-       return -1;
+
+       new = malloc(height * sizeof *new);
+       if (!new) {
+               lbx_errno = -errno;
+               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 *img, int frame)
+{
+       unsigned long size = img->width * img->height;
+
+       assert(img->flags & FLAG_RAW);
+
+       if (img->fops->seek(img->f, img->offsets[frame], SEEK_SET)) {
+               lbx_errno = -errno;
+               return NULL;
+       }
+
+       if (img->fops->read(img->framedata[0], size, img->f) != size) {
+               lbx_errno = -errno;
+               if (img->fops->eof(img->f))
+                       lbx_errno = LBX_EEOF;
+               return NULL;
+       }
+       memset(img->mask[0], 1, size);
+
+       if (img->fops->tell(img->f) > img->offsets[frame+1]) {
+               lbx_errno = LBX_EFORMAT;
+               return NULL;
+       }
+
+       return img->framedata;
 }
 
 unsigned char **lbximg_getframe(struct lbx_image *img, int frame)
@@ -168,42 +304,47 @@ unsigned char **lbximg_getframe(struct lbx_image *img, int frame)
        }
 
        if (!img->framedata) {
-               unsigned char *tmp;
-               int i;
-
-               tmp = malloc(img->width * img->height);
-               if (!tmp) {
-                       lbx_errno = -errno;
+               img->framedata = allocframebuffer(img->width, img->height);
+               if (!img->framedata)
                        return NULL;
-               }
+       }
 
-               img->framedata = malloc(img->height * sizeof *img->framedata);
-               if (!img->framedata) {
-                       lbx_errno = -errno;
-                       free(tmp);
+       if (!img->mask) {
+               img->mask = allocframebuffer(img->width, img->height);
+               if (!img->mask)
                        return NULL;
-               }
-
-               for (i = 0; i < img->height; i++) {
-                       img->framedata[i] = tmp + i * img->width;
-               }
        }
 
-       /* Start over if we are backtracking. */
-       if (img->currentframe > frame)
-               img->currentframe == -1;
+       if (img->flags & FLAG_RAW)
+               return read_raw_frame(img, frame);
 
-       /* We must have previous frame decoded to continue. */
-       if (frame > img->currentframe + 1) {
-               if (!lbximg_getframe(img, frame-1))
-                       return NULL;
+       if ((img->flags & FLAG_OVERWRITE)
+            || (img->chunk && !(frame % img->chunk))) {
+               /* Clear the slate. */
+               img->currentframe = -1;
+               memset(img->framedata[0], 0, img->width * img->height);
+               memset(img->mask[0],      0, img->width * img->height);
+       } else {
+               /* Start over if we are backtracking. */
+               if (img->currentframe > frame) {
+                       memset(img->mask[0], 0, img->width * img->height);
+                       img->currentframe = -1;
+               }
+
+               /* We must have previous frame decoded to continue. */
+               if (frame > img->currentframe + 1) {
+                       if (!lbximg_getframe(img, frame-1))
+                               return NULL;
+               }
        }
 
        if (img->currentframe != frame) {
                int rc, first = 1;
 
-               if (_lbx_fseek(img->f, &img->foff, img->offsets[frame]) == -1)
+               if (img->fops->seek(img->f, img->offsets[frame], SEEK_SET)) {
+                       lbx_errno = -errno;
                        return NULL;
+               }
 
                do {
                        rc = _lbx_drawrow(first, img);
@@ -211,7 +352,7 @@ unsigned char **lbximg_getframe(struct lbx_image *img, int frame)
                                return NULL;
                        first = 0;
 
-                       if (img->foff > img->offsets[frame+1]) {
+                       if (img->fops->tell(img->f) > img->offsets[frame+1]) {
                                lbx_errno = LBX_EFORMAT;
                                return NULL;
                        }
@@ -222,13 +363,15 @@ unsigned char **lbximg_getframe(struct lbx_image *img, int frame)
        return img->framedata;
 }
 
-int lbximg_loadpalette(FILE *f, struct lbx_colour palette[static 256])
+int
+lbximg_loadpalette(void *f, const struct lbx_file_ops *fops,
+                   struct lbx_colour palette[static 256])
 {
-       uint8_t entry[4];
+       unsigned char entry[4];
        int i;
 
        for (i = 0; i < 256; i++) {
-               if (fread(entry, sizeof entry, 1, f) != 1) {
+               if (fops->read(entry, sizeof entry, f) != sizeof entry) {
                        lbx_errno = (feof(f)) ? LBX_EEOF : -errno;
                        return -1;
                }
@@ -238,10 +381,11 @@ int lbximg_loadpalette(FILE *f, struct lbx_colour palette[static 256])
                        return -1;
                }
 
-               palette[i] = (struct lbx_colour){
-                       .red   = entry[1] << 2,
-                       .green = entry[2] << 2,
-                       .blue  = entry[3] << 2,
+               palette[i] = (struct lbx_colour) {
+                       .red    = entry[1] << 2,
+                       .green  = entry[2] << 2,
+                       .blue   = entry[3] << 2,
+                       .active = 1,
                };
        }
 
@@ -251,59 +395,90 @@ int lbximg_loadpalette(FILE *f, struct lbx_colour palette[static 256])
 int
 lbximg_getpalette(struct lbx_image *img, struct lbx_colour palette[static 256])
 {
-       int index = 0;
+       unsigned char entry[4];
+       unsigned int i;
        size_t rc;
-       size_t hdrlen = 6*(sizeof img->width)
-                       + (img->offs)*(sizeof *img->offsets);
-       
-       uint8_t entry[4];
 
-       /* Palette data is located right after the header. */
-       if (_lbx_fseek(img->f, &img->foff, hdrlen) == -1)
+       /* 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)) {
+               lbx_errno = -errno;
                return -1;
-       
-       while (img->foff + sizeof entry <= img->offsets[0]) {
-               rc = fread(entry, 1, sizeof entry, img->f);
-               img->foff += rc;
+       }
 
+       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) {
-                       index++;
-               } else {
-                       index = entry[0];
+               if (entry[0] != 0) {
+                       lbx_errno = LBX_EFORMAT;
+                       return -1;
                }
 
-               palette[index] = (struct lbx_colour){
-                       .red   = entry[1] << 2,
-                       .green = entry[2] << 2,
-                       .blue  = entry[3] << 2,
+               palette[img->palstart + i] = (struct lbx_colour){
+                       .red    = entry[1] << 2,
+                       .green  = entry[2] << 2,
+                       .blue   = entry[3] << 2,
+                       .active = 1,
                };
        }
 
        return 0;
 readerr:
-       if (feof(img->f))
-               lbx_errno = LBX_EEOF;
-       else
-               lbx_errno = -errno;
+       lbx_errno = img->fops->eof(img->f) ? LBX_EEOF : -errno;
        return -1;
 }
 
-void lbximg_close(struct lbx_image *img)
+void lbximg_getinfo(struct lbx_image *img, struct lbx_imginfo *info)
 {
-       if (!img) return;
-
-       if (img->framedata) {
-               free(img->framedata[0]);
-               free(img->framedata);
+       *info = (struct lbx_imginfo) {
+               .width      = img->width,
+               .height     = img->height,
+               .nframes    = img->frames,
+               .chunk      = img->chunk,
+               .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 != img->frames - 1) {
+               info->loopstart = img->leadin;
+               info->looping   = 1;
        }
+}
+
+unsigned char **lbximg_getmask(struct lbx_image *img)
+{
+       return img->mask;
+}
+
+int lbximg_close(struct lbx_image *img)
+{
+       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);
+               }
 
-       if (img->f) {
-               fclose(img->f);
+               free(img);
        }
 
-       free(img);
+       return rc;
 }