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authorMarisa-Chan2014-06-13 21:43:04 +0700
committerMarisa-Chan2014-06-13 21:43:04 +0700
commit45589950c0fb1a449351e6a00ef10d42290d8bae (patch)
tree44e4eedcb7e69d5fc386155b000ed038af07251d /engines/zvision/utility/lzss_read_stream.cpp
parent48360645dcd5f8fddb135b6e31ae5cae4be8d77f (diff)
parent5c005ad3a3f1df0bc968c85c1cf0fc48e36ab0b2 (diff)
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Merge remote-tracking branch 'upstream/master' into zvision
Conflicts: engines/zvision/animation/rlf_animation.cpp engines/zvision/animation_control.h engines/zvision/core/console.cpp engines/zvision/core/events.cpp engines/zvision/cursors/cursor.cpp engines/zvision/cursors/cursor_manager.cpp engines/zvision/cursors/cursor_manager.h engines/zvision/fonts/truetype_font.cpp engines/zvision/graphics/render_manager.cpp engines/zvision/graphics/render_manager.h engines/zvision/inventory/inventory_manager.h engines/zvision/inventory_manager.h engines/zvision/meta_animation.h engines/zvision/module.mk engines/zvision/scripting/actions.cpp engines/zvision/scripting/control.h engines/zvision/scripting/controls/animation_control.cpp engines/zvision/scripting/controls/animation_control.h engines/zvision/scripting/controls/input_control.cpp engines/zvision/scripting/controls/lever_control.cpp engines/zvision/scripting/controls/timer_node.cpp engines/zvision/scripting/controls/timer_node.h engines/zvision/scripting/puzzle.h engines/zvision/scripting/scr_file_handling.cpp engines/zvision/scripting/script_manager.cpp engines/zvision/scripting/script_manager.h engines/zvision/sidefx.cpp engines/zvision/sound/zork_raw.cpp engines/zvision/sound/zork_raw.h engines/zvision/video/video.cpp engines/zvision/video/zork_avi_decoder.h engines/zvision/zvision.cpp engines/zvision/zvision.h
Diffstat (limited to 'engines/zvision/utility/lzss_read_stream.cpp')
-rw-r--r--engines/zvision/utility/lzss_read_stream.cpp103
1 files changed, 103 insertions, 0 deletions
diff --git a/engines/zvision/utility/lzss_read_stream.cpp b/engines/zvision/utility/lzss_read_stream.cpp
new file mode 100644
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--- /dev/null
+++ b/engines/zvision/utility/lzss_read_stream.cpp
@@ -0,0 +1,103 @@
+/* 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 2
+ * 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, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ *
+ */
+
+#include "common/scummsys.h"
+
+#include "zvision/utility/lzss_read_stream.h"
+
+
+namespace ZVision {
+
+LzssReadStream::LzssReadStream(Common::SeekableReadStream *source)
+ : _source(source),
+ // It's convention to set the starting cursor position to blockSize - 16
+ _windowCursor(0x0FEE),
+ _eosFlag(false) {
+ // Clear the window to null
+ memset(_window, 0, BLOCK_SIZE);
+}
+
+uint32 LzssReadStream::decompressBytes(byte *destination, uint32 numberOfBytes) {
+ uint32 destinationCursor = 0;
+
+ while (destinationCursor < numberOfBytes) {
+ byte flagbyte = _source->readByte();
+ if (_source->eos())
+ break;
+ uint mask = 1;
+
+ for (int i = 0; i < 8; ++i) {
+ if ((flagbyte & mask) == mask) {
+ byte data = _source->readByte();
+ if (_source->eos()) {
+ return destinationCursor;
+ }
+
+ _window[_windowCursor] = data;
+ destination[destinationCursor++] = data;
+
+ // Increment and wrap the window cursor
+ _windowCursor = (_windowCursor + 1) & 0xFFF;
+ } else {
+ byte low = _source->readByte();
+ if (_source->eos()) {
+ return destinationCursor;
+ }
+
+ byte high = _source->readByte();
+ if (_source->eos()) {
+ return destinationCursor;
+ }
+
+ uint16 length = (high & 0xF) + 2;
+ uint16 offset = low | ((high & 0xF0) << 4);
+
+ for (int j = 0; j <= length; ++j) {
+ byte temp = _window[(offset + j) & 0xFFF];
+ _window[_windowCursor] = temp;
+ destination[destinationCursor++] = temp;
+ _windowCursor = (_windowCursor + 1) & 0xFFF;
+ }
+ }
+
+ mask = mask << 1;
+ }
+ }
+
+ return destinationCursor;
+}
+
+bool LzssReadStream::eos() const {
+ return _eosFlag;
+}
+
+uint32 LzssReadStream::read(void *dataPtr, uint32 dataSize) {
+ uint32 bytesRead = decompressBytes(static_cast<byte *>(dataPtr), dataSize);
+ if (bytesRead < dataSize) {
+ // Flag that we're at EOS
+ _eosFlag = true;
+ }
+
+ return dataSize;
+}
+
+} // End of namespace ZVision