org.apache.fontbox.ttf.VerticalOriginTable Maven / Gradle / Ivy
/*
* 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.
*/
package org.apache.fontbox.ttf;
import java.io.IOException;
import java.util.Map;
import java.util.concurrent.ConcurrentHashMap;
/**
* A vertical origin 'VORG' table in an OpenType font.
*
* The purpose of this table is to improve the efficiency of determining
* vertical origins in CFF fonts where absent this information the bounding
* box would have to be extracted from CFF charstring data.
*
* This table is strongly recommended by the OpenType CJK Font Guidelines
* for "CFF OpenType fonts that are used for vertical writing".
*
* This table is specified only in the OpenType specification (1.3 and later).
*
* @author Glenn Adams
*
*/
public class VerticalOriginTable extends TTFTable
{
/**
* A tag that identifies this table type.
*/
public static final String TAG = "VORG";
private float version;
private int defaultVertOriginY;
private Map origins;
VerticalOriginTable(TrueTypeFont font)
{
super(font);
}
/**
* This will read the required data from the stream.
*
* @param ttf The font that is being read.
* @param data The stream to read the data from.
* @throws IOException If there is an error reading the data.
*/
@Override
void read(TrueTypeFont ttf, TTFDataStream data) throws IOException
{
version = data.read32Fixed();
defaultVertOriginY = data.readSignedShort();
int numVertOriginYMetrics = data.readUnsignedShort();
origins = new ConcurrentHashMap(numVertOriginYMetrics);
for (int i = 0; i < numVertOriginYMetrics; ++i)
{
int g = data.readUnsignedShort();
int y = data.readSignedShort();
origins.put(g, y);
}
initialized = true;
}
/**
* @return Returns the version.
*/
public float getVersion()
{
return version;
}
/**
* Returns the y-coordinate of the vertical origin for the given GID if known,
* or returns the default value if not specified in table data.
*
* @param gid GID
* @return Returns the y-coordinate of the vertical origin.
*/
public int getOriginY(int gid)
{
if (origins.containsKey(gid))
{
return origins.get(gid);
}
else
{
return defaultVertOriginY;
}
}
}