Add redrle, a program to compress and decompress Town Map tilemaps

hg-commit-id: 42f97a056ab6
2025-09-16 18:30:50 +12:00 · 2011-02-19 00:08:18 -07:00 · 2011-02-19 00:08:18 -07:00 · 3405650fd4
parent 2cad63f7bb
commit 3405650fd4
1 changed files with 134 additions and 0 deletions
--- a/extras/redrle.c
+++ b/extras/redrle.c
@ -0,0 +1,134 @@
+/*
+ * Copyright © 2011 IIMarckus <iimarckus@gmail.com>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+/*
+ * This program compresses or decompresses the Town Map tilemap
+ * from Pokémon Red, Blue, and Yellow.
+ */
+
+#include <stdbool.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+void
+usage()
+{
+	fprintf(stderr, "Usage: redrle [-d] infile outfile\n");
+	exit(1);
+}
+
+int
+main(int argc, char *argv[])
+{
+	FILE *infile, *outfile;
+	bool d = false; /* compress or decompress flag */
+
+	if (argc < 3 || argc > 4)
+		usage();
+
+	if (strcmp(argv[1], "-d") == 0) {
+		if (argc != 4)
+			usage();
+		d = true;
+	}
+
+	infile = fopen(argv[argc - 2], "rb");
+	if (infile == NULL) {
+		fprintf(stderr, "Error opening file '%s': ", argv[argc - 2]);
+		perror(NULL);
+		exit(1);
+	}
+
+	outfile = fopen(argv[argc - 1], "wb");
+	if (outfile == NULL) {
+		fprintf(stderr, "Error opening file '%s': ", argv[argc - 1]);
+		perror(NULL);
+		exit(1);
+	}
+
+	if (d) { /* decompress */
+		for (;;) {
+			int i, count;
+			int byte = fgetc(infile);
+			count = byte & 0xF;
+			byte >>= 4;
+
+			if (byte == 0)
+				break;
+			if (feof(infile)) {
+				fprintf(stderr, "Decompress error: reached "
+				    "end of file without finding terminating "
+				    "null byte.\n");
+				exit(1);
+			}
+			for (i = 0; i < count;
+			    ++i)
+				fputc(byte, outfile);
+		}
+	} else { /* compress */
+		int byte, count = 0, lastbyte = 0;
+		for (;;) {
+			byte = fgetc(infile);
+
+			if (feof(infile)) {
+				while (count > 0xF) {
+					count -= 0xF;
+					fputc(lastbyte << 4 | 0xF, outfile);
+				}
+				if (count != 0) {
+					fputc(lastbyte << 4 | count, outfile);
+				}
+				break;
+			}
+
+			if (byte > 0xF) {
+				fprintf(stderr, "Compress error: read a byte "
+				    "greater than 0xF.\n");
+				exit(1);
+			}
+
+			if (byte == 0) {
+				fprintf(stderr, "Compress error: read a byte "
+				    "of 0x00.\n");
+				exit(1);
+			}
+
+			if (byte == lastbyte)
+				++count;
+			else {
+				while (count > 0xF) {
+					count -= 0xF;
+					fputc(lastbyte << 4 | 0xF, outfile);
+				}
+				if (count != 0) {
+					fputc(lastbyte << 4 | count, outfile);
+					count = 0;
+				}
+
+				lastbyte = byte;
+				count = 1;
+			}
+		}
+
+		fputc(0, outfile); /* Terminating 0x00 */
+	}
+
+	fclose(infile);
+	fclose(outfile);
+
+	return 0;
+}