X-Git-Url: https://git.draconx.ca/gitweb/liblbx.git/blobdiff_plain/9311c2e7ce657110da33c9bc5ebc529b320484b9..91689c5ef8174cc65e1f3ce31f9869778b2af671:/src/image.c

diff --git a/src/image.c b/src/image.c
index 9ad154a..5f3a6e3 100644
--- a/src/image.c
+++ b/src/image.c
@@ -30,19 +30,20 @@
 #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_OVERWRITE|FLAG_BUILDING|FLAG_PALETTE|FLAG_LOOPING)
+#define FLAG_ALL (FLAG_RAW|FLAG_OVERWRITE|FLAG_BUILDING|FLAG_PALETTE|FLAG_LOOPING)
 
 #define HDR_LEN 12
 
 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;
@@ -74,8 +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,
@@ -108,11 +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 */
@@ -265,6 +269,33 @@ static unsigned char **allocframebuffer(size_t width, size_t height)
 	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)
 {
 	if (frame >= img->frames || frame < 0) {
@@ -284,15 +315,21 @@ unsigned char **lbximg_getframe(struct lbx_image *img, int frame)
 			return NULL;
 	}
 
-	if (img->flags & FLAG_OVERWRITE) {
+	if (img->flags & FLAG_RAW)
+		return read_raw_frame(img, frame);
+
+	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)
+		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) {
@@ -402,6 +439,7 @@ 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,
 	};