com.flowpowered.engine.network.codec.ChunkDataCodec.java Source code

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Here is the source code for com.flowpowered.engine.network.codec.ChunkDataCodec.java

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/*
 * This file is part of Flow Engine, licensed under the MIT License (MIT).
 *
 * Copyright (c) 2013 Spout LLC <http://www.spout.org/>
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */
package com.flowpowered.engine.network.codec;

import java.io.IOException;
import java.util.zip.DataFormatException;
import java.util.zip.Deflater;
import java.util.zip.Inflater;

import com.flowpowered.api.geo.cuboid.Chunk;
import com.flowpowered.engine.network.message.ChunkDataMessage;
import com.flowpowered.networking.Codec;

import io.netty.buffer.ByteBuf;

public class ChunkDataCodec implements Codec<ChunkDataMessage> {
    private static final byte ISUNLOAD = 0b1;
    private static final int INTIAL_DATA_SIZE = Chunk.BLOCKS.VOLUME * 2 + Chunk.BLOCKS.VOLUME * 2; // Block Ids, Block Data

    @Override
    public ByteBuf encode(ByteBuf buffer, ChunkDataMessage message) throws IOException {
        if (message.isUnload()) {
            buffer.writeByte(ISUNLOAD); // we're unloading
            buffer.writeInt(message.getX());
            buffer.writeInt(message.getY());
            buffer.writeInt(message.getZ());
        } else {
            int dataSize = INTIAL_DATA_SIZE;

            byte[] uncompressedData = new byte[dataSize];
            byte[] compressedData = new byte[dataSize];

            int index = 0;
            for (int i : message.getBlocks()) {
                uncompressedData[index++] = (byte) i;
                uncompressedData[index++] = (byte) (i >> 8);
                uncompressedData[index++] = (byte) (i >> 16);
                uncompressedData[index++] = (byte) (i >> 24);
            }

            Deflater deflater = new Deflater();
            deflater.setInput(uncompressedData);
            deflater.finish();
            int compressedSize = deflater.deflate(compressedData);
            deflater.end();

            if (compressedSize == 0) {
                throw new IOException("Not all data compressed!");
            }

            buffer.writeByte(0); // Not unload
            buffer.writeInt(message.getX());
            buffer.writeInt(message.getY());
            buffer.writeInt(message.getZ());
            buffer.writeInt(compressedSize);
            buffer.writeBytes(compressedData, 0, compressedSize);
        }
        return buffer;
    }

    @Override
    public ChunkDataMessage decode(ByteBuf buffer) throws IOException {
        final byte info = buffer.readByte();
        final boolean unload = (info & ISUNLOAD) == ISUNLOAD;
        final int x = buffer.readInt();
        final int y = buffer.readInt();
        final int z = buffer.readInt();
        if (unload) {
            return new ChunkDataMessage(x, y, z);
        } else {
            int uncompressedSize = INTIAL_DATA_SIZE;
            final byte[] uncompressedData = new byte[uncompressedSize];
            final byte[] compressedData = new byte[buffer.readInt()];
            buffer.readBytes(compressedData);
            Inflater inflater = new Inflater();
            inflater.setInput(compressedData);
            try {
                inflater.inflate(uncompressedData);
            } catch (DataFormatException e) {
                throw new IOException("Error while reading chunk (" + x + "," + y + "," + z + ")!", e);
            }
            inflater.end();

            final int[] blocks = new int[Chunk.BLOCKS.VOLUME];

            int index = 0;
            for (int i = 0; i < blocks.length; ++i) {
                blocks[i] = uncompressedData[index++] | (uncompressedData[index++] << 8)
                        | (uncompressedData[index++] << 16) | (uncompressedData[index++] << 24);
            }

            if (index != uncompressedData.length) {
                throw new IllegalStateException(
                        "Incorrect parse size - actual:" + index + " expected: " + uncompressedData.length);
            }

            return new ChunkDataMessage(x, y, z, blocks);
        }
    }
}