/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You 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.
*/
/* $Id: AbstractBorderElement.java 426576 2006-07-28 15:44:37Z jeremias $ */
package org.apache.fop.render.txt.border;
import java.awt.Point;
import java.util.Arrays;
import org.apache.fop.area.CTM;
import org.apache.fop.fo.Constants;
import org.apache.fop.render.txt.TXTState;
/**
* This class keeps information about abstract border element, i.e. specifies
* border element for one text position.
*/
public abstract class AbstractBorderElement implements Constants {
/**
* Constant for a line segment, directing from a center of symbol up
* the the symbol boundary.
*/
public static final int UP = 0;
/**
* Constant for a line segment, directing from a center of symbol right
* the the symbol boundary.
*/
public static final int RIGHT = 1;
/**
* Constant for a line segment, directing from a center of symbol down
* the the symbol boundary.
*/
public static final int DOWN = 2;
/**
* Constant for a line segment, directing from a center of symbol left
* the the symbol boundary.
*/
public static final int LEFT = 3;
/**
* I-th element of this array specify, if there line from center of symbol
* to corresponding side (UP, RIGHT, DOWN, LEFT).
*/
protected int[] data = {0, 0, 0, 0};
/**
* Initializes a newly created <code>AbstractBorderElement</code> object
* so that it represents an empty border element.
*/
public AbstractBorderElement() {
}
/**
* Constructs a newly allocated <code>AbstractBorderElement</code> object.
* Fills array <code>data</code> using binary representation of
* <code>type</code>.
*
* @param type binary representation of type gives <code>data</code>
*/
public AbstractBorderElement(int type) {
for (int i = 0; i < 4; i++) {
data[i] = (type >> i) & 1;
}
}
/**
* Returns value of side's element of <code>data</code>.
*
* @param side integer, representing side
* @return value of side's element
*/
public int getData(int side) {
return data[side];
}
/**
* Sets a value for <code>data[side]</code>.
*
* @param side integer, representing side
* @param value a new value for <code>data[side]</code>
*/
public void setData(int side, int value) {
data[side] = value;
}
/**
* Transform border element in according with <code>state</code>.
* @param state instance of TXTState
*/
public void transformElement(TXTState state) {
// here we'll get CTM^-1 without shift
double[] da = state.getResultCTM().toArray();
CTM ctm = new CTM(da[0], -da[1], -da[2], da[3], 0, 0);
Point[] pa = new Point[4];
pa[0] = new Point(0, data[UP]);
pa[1] = new Point(data[RIGHT], 0);
pa[2] = new Point(0, -data[DOWN]);
pa[3] = new Point(-data[LEFT], 0);
Arrays.fill(data, 0);
for (int i = 0; i < 4; i++) {
Point p = state.transformPoint(pa[i], ctm);
int length = (int) p.distance(0, 0);
if (p.x == 0 && p.y > 0) {
data[UP] = length;
} else if (p.x == 0 && p.y < 0) {
data[DOWN] = length;
} else if (p.x > 0 && p.y == 0) {
data[RIGHT] = length;
} else if (p.x < 0 && p.y == 0) {
data[LEFT] = length;
}
}
}
/**
* Merges with border element.
* @param e instance of AbstractBorderElement
* @return instance of AbstractBorderElement
*/
public abstract AbstractBorderElement merge(AbstractBorderElement e);
/**
* Convert internal representation of border element to char.
* @return corresponding char
*/
public abstract char convert2Char();
}