Initial commit

engines/bladerunner/decompress_lcw.cpp

@@ -0,0 +1,133 @@
+/* ScummVM - Graphic Adventure Engine
+ *
+ * ScummVM is the legal property of its developers, whose names
+ * are too numerous to list here. Please refer to the COPYRIGHT
+ * file distributed with this source distribution.
+ *
+ * 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/>.
+ *
+ */
+
+#include "bladerunner/decompress_lcw.h"
+
+#include "common/util.h"
+
+namespace BladeRunner {
+
+uint32 decompress_lcw(uint8 *inBuf, uint32 inLen, uint8 *outBuf, uint32 outLen) {
+	int version = 1;
+	int count, i, color, pos, relpos;
+
+	uint8 *src = inBuf;
+	uint8 *dst = outBuf;
+	uint8 *outEnd = dst + outLen;
+
+	if (src[0] == 0) {
+		version = 2;
+		++src;
+	}
+
+	while (src < inBuf + inLen && dst < outEnd && src[0] != 0x80) {
+		int out_remain = (int)(outEnd - dst);
+
+		if (src[0] == 0xff) {     // 0b11111111
+			count = src[1] | (src[2] << 8);
+			pos   = src[3] | (src[4] << 8);
+			src += 5;
+			count = MIN(count, out_remain);
+
+			if (version == 1) {
+				for (i = 0; i < count; ++i)
+					dst[i] = outBuf[i + pos];
+			} else {
+				for (i = 0; i < count; ++i)
+					dst[i] = *(dst + i - pos);
+			}
+		} else if (src[0] == 0xfe) { // 0b11111110
+			count = src[1] | (src[2] << 8);
+			color = src[3];
+			src += 4;
+			count = MIN(count, out_remain);
+
+			memset(dst, color, count);
+		} else if (src[0] >= 0xc0) { // 0b11??????
+			count = (src[0] & 0x3f) + 3;
+			pos   = src[1] | (src[2] << 8);
+			src += 3;
+			count = MIN(count, out_remain);
+
+			if (version == 1) {
+				for (i = 0; i < count; ++i)
+					dst[i] = outBuf[i + pos];
+			} else {
+				for (i = 0; i < count; ++i)
+					dst[i] = *(dst + i - pos);
+			}
+		} else if (src[0] >= 0x80) { // 0b10??????
+			count = src[0] & 0x3f;
+			++src;
+			count = MIN(count, out_remain);
+
+			memcpy(dst, src, count);
+			src += count;
+		} else {                    // 0b0???????
+			count  = ((src[0] & 0x70) >> 4) + 3;
+			relpos = ((src[0] & 0x0f) << 8) | src[1];
+			src += 2;
+			count = MIN(count, out_remain);
+
+			for (i = 0; i < count; ++i) {
+				dst[i] = *(dst + i - relpos);
+			}
+		}
+
+		dst += count;
+	}
+
+	return uint32(dst - outBuf);
+}
+
+uint32 decompress_lcw_output_size(uint8 *inBuf, uint32 inLen) {
+	int count;
+	uint8 *src     = inBuf;
+	uint32 outsize = 0;
+
+	if (src[0] == 0)
+		++src;
+
+	while (src[0] != 0x80 && src < inBuf + inLen) {
+		if (src[0] == 0xff) {        // 0b11111111
+			count = src[1] | (src[2] << 8);
+			src += 5;
+		} else if (src[0] == 0xfe) { // 0b11111110
+			count = src[1] | (src[2] << 8);
+			src += 4;
+		} else if (src[0] >= 0xc0) { // 0b11??????
+			count = (src[0] & 0x3f) + 3;
+			src += 3;
+		} else if (src[0] & 0x80) {  // 0b10??????
+			count = src[0] & 0x3f;
+			src += count + 1;
+		} else {                    // 0b0???????
+			count  = ((src[0] & 0x70) >> 4) + 3;
+			src += 2;
+		}
+
+		outsize += count;
+	}
+
+	return outsize;
+}
+
+} // End of namespace BladeRunner