From 33cb13dee5a527ac445ea1b13d42723e4eb3e3b0 Mon Sep 17 00:00:00 2001 From: Franklin Wei Date: Mon, 13 Oct 2014 21:00:47 -0400 Subject: Xworld - Another World interpreter for Rockbox Co-conspirators: Franklin Wei, Benjamin Brown -------------------------------------------------------------------- This work is based on: - Fabien Sanglard's "Fabother World" based on - Piotr Padkowski's newRaw interpreter which was based on - Gregory Montoir's reverse engineering of - Eric Chahi's assembly code -------------------------------------------------------------------- Progress: * The plugin runs pretty nicely (with sound!) on most color targets * Keymaps for color LCD targets are complete * The manual entry is finished * Grayscale/monochrome support is NOT PLANNED - the game looks horrible in grayscale! :p -------------------------------------------------------------------- Notes: * The original game strings were built-in to the executable, and were copyrighted and could not be used. * This port ships with an alternate set of strings by default, but can load the "official" strings from a file at runtime. -------------------------------------------------------------------- To be done (in descending order of importance): * vertical stride compatibility <30% done> * optimization <10% done> Change-Id: I3155b0d97c2ac470cb8a2040f40d4139ddcebfa5 Reviewed-on: http://gerrit.rockbox.org/1077 Reviewed-by: Michael Giacomelli --- apps/plugins/xworld/bank.c | 153 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 153 insertions(+) create mode 100644 apps/plugins/xworld/bank.c (limited to 'apps/plugins/xworld/bank.c') diff --git a/apps/plugins/xworld/bank.c b/apps/plugins/xworld/bank.c new file mode 100644 index 0000000000..e2cfbd4680 --- /dev/null +++ b/apps/plugins/xworld/bank.c @@ -0,0 +1,153 @@ +/*************************************************************************** + * __________ __ ___. + * Open \______ \ ____ ____ | | _\_ |__ _______ ___ + * Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ / + * Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < < + * Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \ + * \/ \/ \/ \/ \/ + * $Id$ + * + * Copyright (C) 2014 Franklin Wei, Benjamin Brown + * Copyright (C) 2004 Gregory Montoir + * + * 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 2 + * of the License, or (at your option) any later version. + * + * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY + * KIND, either express or implied. + * + ***************************************************************************/ + +#include "plugin.h" +#include "bank.h" +#include "file.h" +#include "resource.h" + +void bank_create(struct Bank* b, const char *dataDir) +{ + b->_dataDir = dataDir; +} + +bool bank_read(struct Bank* b, const struct MemEntry *me, uint8_t *buf) { + + bool ret = false; + char bankName[10]; + rb->snprintf(bankName, 10, "bank%02x", me->bankId); + File f; + file_create(&f, false); + if (!file_open(&f, bankName, b->_dataDir, "rb")) + error("bank_read() unable to open '%s' in dir '%s'", bankName, b->_dataDir); + + file_seek(&f, me->bankOffset); + + /* Depending if the resource is packed or not we */ + /* can read directly or unpack it. */ + if (me->packedSize == me->size) { + file_read(&f, buf, me->packedSize); + ret = true; + } else { + file_read(&f, buf, me->packedSize); + b->_startBuf = buf; + b->_iBuf = buf + me->packedSize - 4; + ret = bank_unpack(b); + } + file_close(&f); + return ret; +} + +void bank_decUnk1(struct Bank* b, uint8_t numChunks, uint8_t addCount) { + uint16_t count = bank_getCode(b, numChunks) + addCount + 1; + debug(DBG_BANK, "bank_decUnk1(%d, %d) count=%d", numChunks, addCount, count); + b->_unpCtx.datasize -= count; + while (count--) { + assert(b->_oBuf >= b->_iBuf && b->_oBuf >= b->_startBuf); + *b->_oBuf = (uint8_t)bank_getCode(b, 8); + --b->_oBuf; + } +} + +/* + Note from fab: This look like run-length encoding. +*/ +void bank_decUnk2(struct Bank* b, uint8_t numChunks) { + uint16_t i = bank_getCode(b, numChunks); + uint16_t count = b->_unpCtx.size + 1; + debug(DBG_BANK, "bank_decUnk2(%d) i=%d count=%d", numChunks, i, count); + b->_unpCtx.datasize -= count; + while (count--) { + assert(b->_oBuf >= b->_iBuf && b->_oBuf >= b->_startBuf); + *b->_oBuf = *(b->_oBuf + i); + --b->_oBuf; + } +} + +/* + Most resource in the banks are compacted. +*/ +bool bank_unpack(struct Bank* b) { + b->_unpCtx.size = 0; + b->_unpCtx.datasize = READ_BE_UINT32(b->_iBuf); + b->_iBuf -= 4; + b->_oBuf = b->_startBuf + b->_unpCtx.datasize - 1; + b->_unpCtx.crc = READ_BE_UINT32(b->_iBuf); + b->_iBuf -= 4; + b->_unpCtx.chk = READ_BE_UINT32(b->_iBuf); + b->_iBuf -= 4; + b->_unpCtx.crc ^= b->_unpCtx.chk; + do { + if (!bank_nextChunk(b)) { + b->_unpCtx.size = 1; + if (!bank_nextChunk(b)) { + bank_decUnk1(b, 3, 0); + } else { + bank_decUnk2(b, 8); + } + } else { + uint16_t c = bank_getCode(b, 2); + if (c == 3) { + bank_decUnk1(b, 8, 8); + } else { + if (c < 2) { + b->_unpCtx.size = c + 2; + bank_decUnk2(b, c + 9); + } else { + b->_unpCtx.size = bank_getCode(b, 8); + bank_decUnk2(b, 12); + } + } + } + } while (b->_unpCtx.datasize > 0); + return (b->_unpCtx.crc == 0); +} + +uint16_t bank_getCode(struct Bank* b, uint8_t numChunks) { + uint16_t c = 0; + while (numChunks--) { + c <<= 1; + if (bank_nextChunk(b)) { + c |= 1; + } + } + return c; +} + +bool bank_nextChunk(struct Bank* b) { + bool CF = bank_rcr(b, false); + if (b->_unpCtx.chk == 0) { + assert(b->_iBuf >= b->_startBuf); + b->_unpCtx.chk = READ_BE_UINT32(b->_iBuf); + b->_iBuf -= 4; + b->_unpCtx.crc ^= b->_unpCtx.chk; + CF = bank_rcr(b, true); + } + return CF; +} + +bool bank_rcr(struct Bank* b, bool CF) { + bool rCF = (b->_unpCtx.chk & 1); + b->_unpCtx.chk >>= 1; + if (CF) b->_unpCtx.chk |= 0x80000000; + return rCF; +} -- cgit v1.2.3