X-Git-Url: https://git.draconx.ca/gitweb/liblbx.git/blobdiff_plain/c1de95057ed86c206b9583bd21fcc2d6d4744e6c..91689c5ef8174cc65e1f3ce31f9869778b2af671:/src/image.c

diff --git a/src/image.c b/src/image.c
index 9bc4985..5f3a6e3 100644
--- a/src/image.c
+++ b/src/image.c
@@ -30,21 +30,27 @@
 #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_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;
 
-	FILE *f;
-	long foff, paloff;
+	const struct lbx_file_ops *fops;
+	int (*dtor)(void *handle);
+	void *f;
+
+	long paloff;
 
 	int currentframe;
 	int currentx, currenty;
@@ -69,8 +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,
@@ -79,15 +87,15 @@ static struct lbx_image *lbximg_init(unsigned char hdr[static HDR_LEN])
 	return img;
 }
 
-struct lbx_image *lbximg_fopen(FILE *f)
+struct lbx_image *lbximg_open(void *f, const struct lbx_file_ops *fops,
+                              int (*destructor)(void *))
 {
 	unsigned char hdr_buf[HDR_LEN];
 	struct lbx_image *img;
-	size_t rc;
 
-	if (fread(hdr_buf, 1, sizeof hdr_buf, f) != sizeof hdr_buf) {
+	if (fops->read(hdr_buf, sizeof hdr_buf, f) != sizeof hdr_buf) {
 		lbx_errno = -errno;
-		if (feof(f))
+		if (fops->eof(f))
 			lbx_errno = LBX_EEOF;
 		return NULL;
 	}
@@ -97,40 +105,41 @@ struct lbx_image *lbximg_fopen(FILE *f)
 		return NULL;
 
 	img->f    = f;
-	img->foff = sizeof hdr_buf;
+	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(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 */
 	for (unsigned i = 0; i <= img->frames; i++) {
 		unsigned char buf[4];
 
-		if (fread(buf, 1, sizeof buf, f) != sizeof buf) {
+		if (fops->read(buf, sizeof buf, f) != sizeof buf) {
 			lbx_errno = -errno;
-			if (feof(f))
+			if (fops->eof(f))
 				lbx_errno = LBX_EEOF;
 			free(img);
 			return NULL;
 		}
 
 		img->offsets[i] = unpack_32_le(buf);
-		img->foff += 4;
 	}
 
 	if (img->flags & FLAG_PALETTE) {
 		unsigned char buf[4];
 
-		if (fread(buf, 1, sizeof buf, f) != sizeof buf) {
+		if (fops->read(buf, sizeof buf, f) != sizeof buf) {
 			lbx_errno = -errno;
-			if (feof(f))
+			if (fops->eof(f))
 				lbx_errno = LBX_EEOF;
 			free(img);
 			return NULL;
@@ -138,8 +147,7 @@ struct lbx_image *lbximg_fopen(FILE *f)
 
 		img->palstart = unpack_16_le(buf+0);
 		img->palcount = unpack_16_le(buf+2);
-		img->foff    += sizeof buf;
-		img->paloff   = img->foff;
+		img->paloff   = fops->tell(f);
 
 		if (img->palstart + img->palcount > 256) {
 			lbx_errno = LBX_EFORMAT;
@@ -151,6 +159,11 @@ struct lbx_image *lbximg_fopen(FILE *f)
 	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)
 {
 	unsigned short type, count, yval, xval;
@@ -161,9 +174,8 @@ static int _lbx_drawrow(int first, struct lbx_image *img)
 	assert(img->framedata);
 	assert(img->mask);
 
-	if (fread(buf, 1, sizeof buf, img->f) != sizeof buf)
+	if (img->fops->read(buf, sizeof buf, img->f) != sizeof buf)
 		goto readerr;
-	img->foff += 4;
 	type = unpack_16_le(buf+0);
 
 	if (first) {
@@ -177,9 +189,8 @@ static int _lbx_drawrow(int first, struct lbx_image *img)
 		if (yval == 1000)
 			return 1;
 
-		if (fread(buf, 1, sizeof buf, img->f) != sizeof buf)
+		if (img->fops->read(buf, sizeof buf, img->f) != sizeof buf)
 			goto readerr;
-		img->foff += 4;
 		count = unpack_16_le(buf+0);
 
 		xval = unpack_16_le(buf+2);
@@ -214,26 +225,22 @@ static int _lbx_drawrow(int first, struct lbx_image *img)
 	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(buf, 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 {
-		lbx_errno = -errno;
-	}
 	return -1;
 }
 
@@ -262,6 +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) {
@@ -281,15 +315,22 @@ unsigned char **lbximg_getframe(struct lbx_image *img, int frame)
 			return NULL;
 	}
 
-	/* Start over if we are backtracking. */
-	if (img->currentframe > frame)
-		img->currentframe == -1;
+	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);
 		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))
@@ -300,8 +341,10 @@ unsigned char **lbximg_getframe(struct lbx_image *img, int frame)
 	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);
@@ -309,7 +352,7 @@ unsigned char **lbximg_getframe(struct lbx_image *img, int frame)
 				return NULL;
 			first = 0;
 
-			if (!rc && img->foff > img->offsets[frame+1]) {
+			if (img->fops->tell(img->f) > img->offsets[frame+1]) {
 				lbx_errno = LBX_EFORMAT;
 				return NULL;
 			}
@@ -320,13 +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])
 {
 	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;
 		}
@@ -336,10 +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,
 		};
 	}
 
@@ -357,13 +403,13 @@ lbximg_getpalette(struct lbx_image *img, struct lbx_colour palette[static 256])
 	if (!(img->flags & FLAG_PALETTE))
 		return 0;
 
-	if (_lbx_fseek(img->f, &img->foff, img->paloff) == -1)
+	if (img->fops->seek(img->f, img->paloff, SEEK_SET)) {
+		lbx_errno = -errno;
 		return -1;
+	}
 
 	for (i = 0; i < img->palcount; i++) {
-		rc = fread(entry, 1, sizeof entry, img->f);
-		img->foff += rc;
-
+		rc = img->fops->read(entry, sizeof entry, img->f);
 		if (rc < sizeof entry) {
 			goto readerr;
 		}
@@ -374,15 +420,16 @@ lbximg_getpalette(struct lbx_image *img, struct lbx_colour palette[static 256])
 		}
 
 		palette[img->palstart + i] = (struct lbx_colour){
-			.red   = entry[1] << 2,
-			.green = entry[2] << 2,
-			.blue  = entry[3] << 2,
+			.red    = entry[1] << 2,
+			.green  = entry[2] << 2,
+			.blue   = entry[3] << 2,
+			.active = 1,
 		};
 	}
 
 	return 0;
 readerr:
-	lbx_errno = feof(img->f) ? LBX_EEOF : -errno;
+	lbx_errno = img->fops->eof(img->f) ? LBX_EEOF : -errno;
 	return -1;
 }
 
@@ -392,6 +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,
 	};
 
@@ -410,23 +458,27 @@ unsigned char **lbximg_getmask(struct lbx_image *img)
 	return img->mask;
 }
 
-void lbximg_close(struct lbx_image *img)
+int lbximg_close(struct lbx_image *img)
 {
-	if (!img) return;
+	int rc = 0;
 
-	if (img->framedata) {
-		free(img->framedata[0]);
-		free(img->framedata);
-	}
+	if (img) {
+		if (img->framedata) {
+			free(img->framedata[0]);
+			free(img->framedata);
+		}
 
-	if (img->mask) {
-		free(img->mask[0]);
-		free(img->mask);
-	}
+		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;
 }