/*
* FontAlignment.java
* Transform
*
* Copyright (c) 2009-2010 Flagstone Software Ltd. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* * Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
* * Neither the name of Flagstone Software Ltd. nor the names of its
* contributors may be used to endorse or promote products derived from this
* software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
package com.flagstone.transform.font;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import com.flagstone.transform.Constants;
import com.flagstone.transform.MovieTag;
import com.flagstone.transform.MovieTypes;
import com.flagstone.transform.coder.Coder;
import com.flagstone.transform.coder.Context;
import com.flagstone.transform.coder.SWFDecoder;
import com.flagstone.transform.coder.SWFEncoder;
import com.flagstone.transform.exception.IllegalArgumentRangeException;
/**
* FontAlignment provides the alignment information for the glyphs in a font.
*/
public final class FontAlignment implements MovieTag {
/**
* StrokeWidth is used to provide hints about the thickness of the line
* used for rendering glyphs in a font.
*/
public enum StrokeWidth {
/** Thin strokes. */
THIN,
/** Medium thick strokes. */
MEDIUM,
/** Thick strokes. */
THICK
};
/** Format string used in toString() method. */
private static final String FORMAT = "FontAlignment: { identifier=%d;"
+ " strokeWidth=%s; zones=%s}";
/** The unique identifier of the font that the alignment applies to. */
private int identifier;
/** Compound code used for drawing hints. */
private transient int hints;
/** Alignment zones for snapping areas of glyphs to pixel boundaries. */
private List<GlyphAlignment> zones;
/** The length of the object, minus the header, when it is encoded. */
private transient int length;
/**
* Creates and initialises a FontAlignment object using values encoded
* in the Flash binary format.
*
* @param coder
* an SWFDecoder object that contains the encoded Flash data.
*
* @throws IOException
* if an error occurs while decoding the data.
*/
public FontAlignment(final SWFDecoder coder) throws IOException {
length = coder.readUnsignedShort() & Coder.LENGTH_FIELD;
if (length == Coder.IS_EXTENDED) {
length = coder.readInt();
}
coder.mark();
identifier = coder.readUnsignedShort();
hints = coder.readByte();
zones = new ArrayList<GlyphAlignment>();
while (coder.bytesRead() < length) {
zones.add(new GlyphAlignment(coder));
}
coder.check(length);
coder.unmark();
}
/**
* Creates a new FontAlignment object for the referenced font along with
* information on the stroke width used to draw the glyphs and a list of
* alignment zones for each glyph.
* @param uid the unique identifier of the font.
* @param stroke the typical width used when drawing the glyphs.
* @param list a list of alignment boxes used for rendering the glyphs.
*/
public FontAlignment(final int uid, final StrokeWidth stroke,
final List<GlyphAlignment> list) {
setIdentifier(uid);
setStrokeWidth(stroke);
setZones(list);
}
/**
* Creates and initialises a FontAlignment object using the values copied
* from another FontAlignment object.
*
* @param object
* a FontAlignment object from which the values will be
* copied.
*/
public FontAlignment(final FontAlignment object) {
identifier = object.identifier;
hints = object.hints;
zones = new ArrayList<GlyphAlignment>(object.zones);
}
/**
* Get the unique identifier of the font definition that the alignment
* information is for.
*
* @return the unique identifier of the font.
*/
public int getIdentifier() {
return identifier;
}
/**
* Sets the identifier of the font that this alignment information is for.
*
* @param uid
* the unique identifier of the DefineFont that contains the
* glyphs for the font. Must be in the range 1..65535.
*/
public void setIdentifier(final int uid) {
if ((uid < 1) || (uid > Coder.USHORT_MAX)) {
throw new IllegalArgumentRangeException(
1, Coder.USHORT_MAX, uid);
}
identifier = uid;
}
/**
* Get the StrokeWidth that describes how the glyphs in the font are
* typically drawn.
* @return a StrokeWidth defining how the font is drawn.
*/
public StrokeWidth getStrokeWidth() {
StrokeWidth stroke;
switch (hints) {
case Coder.BIT6:
stroke = StrokeWidth.MEDIUM;
break;
case Coder.BIT7:
stroke = StrokeWidth.THICK;
break;
default:
stroke = StrokeWidth.THIN;
break;
}
return stroke;
}
/**
* Set the StrokeWidth that describes how the glyphs in the font are
* typically drawn.
* @param stroke a StrokeWidth defining how the font is drawn.
*/
public void setStrokeWidth(final StrokeWidth stroke) {
switch (stroke) {
case MEDIUM:
hints = Coder.BIT6;
break;
case THICK:
hints = Coder.BIT7;
break;
default:
hints = 0x00;
break;
}
}
/**
* Get the alignment information for each glyph in the font.
* @return a list of GlyphAliment objects that describe the areas in each
* glyph which can be snapped to the nearest pixel to improve display
* quality.
*/
public List<GlyphAlignment> getZones() {
return zones;
}
/**
* Set the alignment information for each glyph in the font.
* @param list a list of GlyphAliment objects that describe the areas in
* each glyph which can be snapped to the nearest pixel to improve display
* quality.
*/
public void setZones(final List<GlyphAlignment> list) {
if (list == null) {
throw new IllegalArgumentException();
}
zones = list;
}
/**
* Add the alignment information for a glyph to the list.
* @param zone the alignment information for a glyph.
* @return this object.
*/
public FontAlignment addZone(final GlyphAlignment zone) {
if (zone == null) {
throw new IllegalArgumentException();
}
zones.add(zone);
return this;
}
/** {@inheritDoc} */
public FontAlignment copy() {
return new FontAlignment(this);
}
@Override
public String toString() {
return String.format(FORMAT, identifier, getStrokeWidth(), zones);
}
/** {@inheritDoc} */
public int prepareToEncode(final Context context) {
// CHECKSTYLE IGNORE MagicNumberCheck FOR NEXT 1 LINES
length = 3;
for (final GlyphAlignment zone : zones) {
length += zone.prepareToEncode(context);
}
return (length > Coder.HEADER_LIMIT ? Coder.LONG_HEADER
: Coder.SHORT_HEADER) + length;
}
/** {@inheritDoc} */
public void encode(final SWFEncoder coder, final Context context)
throws IOException {
if (length > Coder.HEADER_LIMIT) {
coder.writeShort((MovieTypes.FONT_ALIGNMENT
<< Coder.LENGTH_FIELD_SIZE) | Coder.IS_EXTENDED);
coder.writeInt(length);
} else {
coder.writeShort((MovieTypes.FONT_ALIGNMENT
<< Coder.LENGTH_FIELD_SIZE) | length);
}
if (Constants.DEBUG) {
coder.mark();
}
coder.writeShort(identifier);
coder.writeByte(hints);
for (final GlyphAlignment zone : zones) {
zone.encode(coder, context);
}
if (Constants.DEBUG) {
coder.check(length);
coder.unmark();
}
}
}