SparseMatrix.java

/**
 * Copyright 2014 
 * SMEdit https://github.com/StarMade/SMEdit
 * SMTools https://github.com/StarMade/SMTools
 *
 * Licensed under the Apache License, Version 2.0 (the "License"); you may not
 * use this file except in compliance with the License. You may obtain a copy of
 * the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
 * License for the specific language governing permissions and limitations under
 * the License.
 **/
package jo.sm.data;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;

import jo.sm.logic.utils.ByteUtils;
import jo.vecmath.Point3i;
import jo.vecmath.Point3s;

/**
 * @Auther Jo Jaquinta for SMEdit Classic - version 1.0
 **/
public final class SparseMatrix<T> {

    public static long toHashCode(int x, int y, int z) {
        byte[] buffer = new byte[8];
        buffer[0] = 0;
        ByteUtils.toBytes((short) x, buffer, 1);
        ByteUtils.toBytes((short) y, buffer, 3);
        ByteUtils.toBytes((short) z, buffer, 5);
        buffer[7] = 1;
        return ByteUtils.toLong(buffer);
    }

    public static Point3i fromHashCode(long hash) {
        byte[] buffer = new byte[8];
        ByteUtils.toBytes(hash, buffer);
        short x = ByteUtils.toShort(buffer, 1);
        short y = ByteUtils.toShort(buffer, 3);
        short z = ByteUtils.toShort(buffer, 5);
        Point3i p = new Point3i(x, y, z);
        return p;
    }

    private Map<Long, T> mMatrix;
    private Point3i mLower;
    private Point3i mUpper;

    public SparseMatrix() {
        mMatrix = new HashMap<>();
        mLower = null;
        mUpper = null;
    }

    public SparseMatrix(SparseMatrix<T> original) {
        this();
        set(original);
        mLower = new Point3i();
        mUpper = new Point3i();
        original.getBounds(mLower, mUpper);
    }

    public void addAll(SparseMatrix<T> original) {
        for (Iterator<Point3i> i = original.iteratorNonNull(); i.hasNext();) {
            Point3i p = i.next();
            set(p, original.get(p));
        }
    }

    public void set(SparseMatrix<T> original) {
        mMatrix.clear();
        addAll(original);
    }

    public void set(int x, int y, int z, T val) {
        long idx = toHashCode(x, y, z);
        if (val == null) {
            mMatrix.remove(idx);
        } else {
            mMatrix.put(idx, val);
        }
        if (val != null) {
            if (mLower == null) {
                mLower = new Point3i(x, y, z);
            } else {
                mLower.x = Math.min(mLower.x, x);
                mLower.y = Math.min(mLower.y, y);
                mLower.z = Math.min(mLower.z, z);
            }
            if (mUpper == null) {
                mUpper = new Point3i(x, y, z);
            } else {
                mUpper.x = Math.max(mUpper.x, x);
                mUpper.y = Math.max(mUpper.y, y);
                mUpper.z = Math.max(mUpper.z, z);
            }
        }
    }

    public T get(int x, int y, int z) {
        long idx = toHashCode(x, y, z);
        return mMatrix.get(idx);
    }

    public boolean contains(int x, int y, int z) {
        return get(x, y, z) != null;
    }

    public void set(Point3i v, T val) {
        set(v.x, v.y, v.z, val);
    }

    public T get(Point3i v) {
        return get(v.x, v.y, v.z);
    }

    public T get(Point3s v) {
        return get(v.x, v.y, v.z);
    }

    public boolean contains(Point3i v) {
        return get(v.x, v.y, v.z) != null;
    }

    public void getBounds(Point3i lower, Point3i upper) {
        if (mLower != null) {
            lower.set(mLower);
        }
        if (mUpper != null) {
            upper.set(mUpper);
        }
    }

    public Iterator<Point3i> iterator() {
        return new CubeIterator(mLower, mUpper);
    }

    public Iterator<Point3i> iteratorNonNull() {
        List<Point3i> points = new ArrayList<>();
        for (Long l : mMatrix.keySet()) {
            Point3i p = fromHashCode(l);
            points.add(p);
        }
        return points.iterator();
    }

    public int size() {
        return mMatrix.size();
    }

}