X-Git-Url: https://git.draconx.ca/gitweb/liblbx.git/blobdiff_plain/bdad20799885211ac4c76bdaef5b027552d6241d..f8295b32a98df79caee16a25a1dcf3a7a678e409:/src/image.c

diff --git a/src/image.c b/src/image.c
index 21f5a8e..cc8d54b 100644
--- a/src/image.c
+++ b/src/image.c
@@ -1,7 +1,7 @@
 /*
  *  2ooM: The Master of Orion II Reverse Engineering Project
  *  Library for working with LBX image files.
- *  Copyright (C) 2006-2008 Nick Bowler
+ *  Copyright (C) 2006-2010 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
@@ -43,7 +43,7 @@
 struct lbx_image {
 	unsigned short width, height;
 	unsigned short wtf, flags;
-	unsigned short frames, leadin;
+	unsigned char  frames, wtf2, leadin, chunk;
 	unsigned short palstart, palcount;
 
 	const struct lbx_file_ops *fops;
@@ -75,8 +75,10 @@ static struct lbx_image *lbximg_init(unsigned char hdr[static HDR_LEN])
 		.width  = unpack_16_le(hdr+0),
 		.height = unpack_16_le(hdr+2),
 		.wtf    = unpack_16_le(hdr+4),
-		.frames = unpack_16_le(hdr+6),
-		.leadin = unpack_16_le(hdr+8),
+		.frames = hdr[6],
+		.wtf2   = hdr[7],
+		.leadin = hdr[8],
+		.chunk  = hdr[9],
 		.flags  = unpack_16_le(hdr+10),
 
 		.currentframe = -1,
@@ -109,11 +111,12 @@ struct lbx_image *lbximg_open(void *f, const struct lbx_file_ops *fops,
 	/*
 	 * 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(img->wtf == 0); /* version? */
-	_lbx_assert(img->frames > img->leadin); /* cmbtshp.lbx breaks this. */
+	_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));
 
 	/* Read all offsets.  Should be merged with identical code in lbx.c */
@@ -156,9 +159,41 @@ struct lbx_image *lbximg_open(void *f, const struct lbx_file_ops *fops,
 	return img;
 }
 
-struct lbx_image *lbximg_fopen(FILE *f)
+static int pipe_close(void *f)
 {
-	return lbximg_open(f, &lbx_default_fops, NULL);
+	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 *lbximg_fopen(const char *file)
+{
+	struct lbx_pipe_state *p;
+	FILE *f;
+
+	f = fopen(file, "rb");
+	if (!f)
+		return NULL;
+
+	if (fseek(f, 0, SEEK_CUR) == 0)
+		return lbximg_open(f, &lbx_default_fops, file_close);
+
+	p = malloc(sizeof *p);
+	if (!p) {
+		fclose(f);
+		return NULL;
+	}
+
+	*p = (struct lbx_pipe_state) { .f = f };
+	return lbximg_open(p, &lbx_pipe_fops, pipe_close);
 }
 
 static int _lbx_drawrow(int first, struct lbx_image *img)
@@ -315,7 +350,8 @@ unsigned char **lbximg_getframe(struct lbx_image *img, int frame)
 	if (img->flags & FLAG_RAW)
 		return read_raw_frame(img, frame);
 
-	if (img->flags & FLAG_OVERWRITE) {
+	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);
@@ -435,6 +471,7 @@ void lbximg_getinfo(struct lbx_image *img, struct lbx_imginfo *info)
 		.width      = img->width,
 		.height     = img->height,
 		.nframes    = img->frames,
+		.chunk      = img->chunk,
 		.palettesz  = (img->flags & FLAG_PALETTE) ? img->palcount : 0,
 	};