/*
* 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.
*/
/*
* @author Oleg V. Khaschansky
* @version $Revision$
*/
package org.apache.harmony.awt.gl.font;
import java.awt.BasicStroke;
import java.awt.Color;
import java.awt.Graphics2D;
import java.awt.Paint;
import java.awt.Shape;
import java.awt.Stroke;
import java.awt.font.TextAttribute;
import java.awt.geom.Area;
import java.awt.geom.Line2D;
import java.awt.geom.Rectangle2D;
import java.text.AttributedCharacterIterator.Attribute;
import java.util.Map;
/**
* This class is responsible for rendering text decorations like
* underline, strikethrough, text with background, etc.
*/
public class TextDecorator {
private static final TextDecorator inst = new TextDecorator();
private TextDecorator() {}
static TextDecorator getInstance() {
return inst;
}
/**
* This class encapsulates a set of decoration attributes for a single text run.
*/
static class Decoration {
private static final BasicStroke UNDERLINE_LOW_ONE_PIXEL_STROKE =
new BasicStroke(1, BasicStroke.CAP_BUTT, BasicStroke.JOIN_MITER, 10);
private static final BasicStroke UNDERLINE_LOW_TWO_PIXEL_STROKE =
new BasicStroke(2, BasicStroke.CAP_BUTT, BasicStroke.JOIN_MITER, 10);
private static final BasicStroke UNDERLINE_LOW_DOTTED_STROKE =
new BasicStroke(
1, BasicStroke.CAP_BUTT, BasicStroke.JOIN_MITER, 10,
new float[] { 1, 1 }, 0
);
private static final BasicStroke UNDERLINE_LOW_DOTTED_STROKE2 =
new BasicStroke(
1, BasicStroke.CAP_BUTT, BasicStroke.JOIN_MITER, 10,
new float[] { 1, 1 }, 1
);
private static final BasicStroke UNDERLINE_LOW_DASHED_STROKE =
new BasicStroke(
1, BasicStroke.CAP_BUTT, BasicStroke.JOIN_MITER, 10,
new float[] { 4, 4 }, 0
);
boolean ulOn = false; // Have standard underline?
BasicStroke ulStroke;
BasicStroke imUlStroke; // Stroke for INPUT_METHOD_UNDERLINE
BasicStroke imUlStroke2; // Specially for UNDERLINE_LOW_GRAY
boolean strikeThrough;
BasicStroke strikeThroughStroke;
boolean haveStrokes = false; // Strokes already created?
boolean swapBfFg;
Paint bg; // background color
Paint fg; // foreground color
Paint graphicsPaint; // Slot for saving current paint
Decoration(
Integer imUl,
boolean swap,
boolean sth,
Paint bg, Paint fg,
boolean ulOn) {
if (imUl != null) {
// Determine which stroke to use
if (imUl == TextAttribute.UNDERLINE_LOW_ONE_PIXEL) {
this.imUlStroke = Decoration.UNDERLINE_LOW_ONE_PIXEL_STROKE;
} else if (imUl == TextAttribute.UNDERLINE_LOW_TWO_PIXEL) {
this.imUlStroke = Decoration.UNDERLINE_LOW_TWO_PIXEL_STROKE;
} else if (imUl == TextAttribute.UNDERLINE_LOW_DOTTED) {
this.imUlStroke = Decoration.UNDERLINE_LOW_DOTTED_STROKE;
} else if (imUl == TextAttribute.UNDERLINE_LOW_GRAY) {
this.imUlStroke = Decoration.UNDERLINE_LOW_DOTTED_STROKE;
this.imUlStroke2 = Decoration.UNDERLINE_LOW_DOTTED_STROKE2;
} else if (imUl == TextAttribute.UNDERLINE_LOW_DASHED) {
this.imUlStroke = Decoration.UNDERLINE_LOW_DASHED_STROKE;
}
}
this.ulOn = ulOn; // Has underline
this.swapBfFg = swap;
this.strikeThrough = sth;
this.bg = bg;
this.fg = fg;
}
/**
* Creates strokes of proper width according to the info
* stored in the BasicMetrics
* @param metrics - basic metrics
*/
private void getStrokes(BasicMetrics metrics) {
if (!haveStrokes) {
if (strikeThrough) {
strikeThroughStroke =
new BasicStroke(
metrics.strikethroughThickness,
BasicStroke.CAP_BUTT,
BasicStroke.JOIN_MITER,
10
);
}
if (ulOn) {
ulStroke =
new BasicStroke(
metrics.underlineThickness,
BasicStroke.CAP_BUTT,
BasicStroke.JOIN_MITER,
10
);
}
haveStrokes = true;
}
}
}
/**
* Creates Decoration object from the set of text attributes
* @param attributes - text attributes
* @return Decoration object
*/
static Decoration getDecoration(Map<? extends Attribute, ?> attributes) {
if (attributes == null) {
return null; // It is for plain text
}
Object underline = attributes.get(TextAttribute.UNDERLINE);
boolean hasStandardUnderline = underline == TextAttribute.UNDERLINE_ON;
Object imUnderline = attributes.get(TextAttribute.INPUT_METHOD_UNDERLINE);
Integer imUl = (Integer) imUnderline;
boolean swapBgFg =
TextAttribute.SWAP_COLORS_ON.equals(
attributes.get(TextAttribute.SWAP_COLORS)
);
boolean strikeThrough =
TextAttribute.STRIKETHROUGH_ON.equals(
attributes.get(TextAttribute.STRIKETHROUGH)
);
Paint fg = (Paint) attributes.get(TextAttribute.FOREGROUND);
Paint bg = (Paint) attributes.get(TextAttribute.BACKGROUND);
if (
!hasStandardUnderline &&
imUnderline == null &&
fg == null &&
bg == null &&
!swapBgFg &&
!strikeThrough
) {
return null;
}
return new Decoration(imUl, swapBgFg, strikeThrough, bg, fg, hasStandardUnderline);
}
/**
* Fills the background before drawing if needed.
*
* @param trs - text segment
* @param g2d - graphics to draw to
* @param xOffset - offset in X direction to the upper left corner of the
* layout from the origin of the graphics
* @param yOffset - offset in Y direction to the upper left corner of the
* layout from the origin of the graphics
*/
static void prepareGraphics(
TextRunSegment trs, Graphics2D g2d,
float xOffset, float yOffset
) {
Decoration d = trs.decoration;
if (d.fg == null && d.bg == null && d.swapBfFg == false) {
return; // Nothing to do
}
d.graphicsPaint = g2d.getPaint();
if (d.fg == null) {
d.fg = d.graphicsPaint;
}
if (d.swapBfFg) {
// Fill background area
g2d.setPaint(d.fg);
Rectangle2D bgArea = trs.getLogicalBounds();
Rectangle2D toFill =
new Rectangle2D.Double(
bgArea.getX() + xOffset,
bgArea.getY() + yOffset,
bgArea.getWidth(),
bgArea.getHeight()
);
g2d.fill(toFill);
// Set foreground color
g2d.setPaint(d.bg == null ? Color.WHITE : d.bg);
} else {
if (d.bg != null) { // Fill background area
g2d.setPaint(d.bg);
Rectangle2D bgArea = trs.getLogicalBounds();
Rectangle2D toFill =
new Rectangle2D.Double(
bgArea.getX() + xOffset,
bgArea.getY() + yOffset,
bgArea.getWidth(),
bgArea.getHeight()
);
g2d.fill(toFill);
}
// Set foreground color
g2d.setPaint(d.fg);
}
}
/**
* Restores the original state of the graphics if needed
* @param d - decoration
* @param g2d - graphics
*/
static void restoreGraphics(Decoration d, Graphics2D g2d) {
if (d.fg == null && d.bg == null && d.swapBfFg == false) {
return; // Nothing to do
}
g2d.setPaint(d.graphicsPaint);
}
/**
* Renders the text decorations
* @param trs - text run segment
* @param g2d - graphics to render to
* @param xOffset - offset in X direction to the upper left corner
* of the layout from the origin of the graphics
* @param yOffset - offset in Y direction to the upper left corner
* of the layout from the origin of the graphics
*/
static void drawTextDecorations(
TextRunSegment trs, Graphics2D g2d,
float xOffset, float yOffset
) {
Decoration d = trs.decoration;
if (!d.ulOn && d.imUlStroke == null && !d.strikeThrough) {
return; // Nothing to do
}
float left = xOffset + (float) trs.getLogicalBounds().getMinX();
float right = xOffset + (float) trs.getLogicalBounds().getMaxX();
Stroke savedStroke = g2d.getStroke();
d.getStrokes(trs.metrics);
if (d.strikeThrough) {
float y = trs.y + yOffset + trs.metrics.strikethroughOffset;
g2d.setStroke(d.strikeThroughStroke);
g2d.draw(new Line2D.Float(left, y, right, y));
}
if (d.ulOn) {
float y = trs.y + yOffset + trs.metrics.underlineOffset;
g2d.setStroke(d.ulStroke);
g2d.draw(new Line2D.Float(left, y, right, y));
}
if (d.imUlStroke != null) {
float y = trs.y + yOffset + trs.metrics.underlineOffset;
g2d.setStroke(d.imUlStroke);
g2d.draw(new Line2D.Float(left, y, right, y));
if (d.imUlStroke2 != null) {
y++;
g2d.setStroke(d.imUlStroke2);
g2d.draw(new Line2D.Float(left, y, right, y));
}
}
g2d.setStroke(savedStroke);
}
/**
* Extends the visual bounds of the text run segment to
* include text decorations.
* @param trs - text segment
* @param segmentBounds - bounds of the undecorated text
* @param d - decoration
* @return extended bounds
*/
static Rectangle2D extendVisualBounds(
TextRunSegment trs,
Rectangle2D segmentBounds,
Decoration d
) {
if (d == null) {
return segmentBounds;
}
double minx = segmentBounds.getMinX();
double miny = segmentBounds.getMinY();
double maxx = segmentBounds.getMaxX();
double maxy = segmentBounds.getMaxY();
Rectangle2D lb = trs.getLogicalBounds();
if (d.swapBfFg || d.bg != null) {
minx = Math.min(lb.getMinX() - trs.x, minx);
miny = Math.min(lb.getMinY() - trs.y, miny);
maxx = Math.max(lb.getMaxX() - trs.x, maxx);
maxy = Math.max(lb.getMaxY() - trs.y, maxy);
}
if (d.ulOn || d.imUlStroke != null || d.strikeThrough) {
minx = Math.min(lb.getMinX() - trs.x, minx);
maxx = Math.max(lb.getMaxX() - trs.x, maxx);
d.getStrokes(trs.metrics);
if (d.ulStroke != null) {
maxy = Math.max(
maxy,
trs.metrics.underlineOffset +
d.ulStroke.getLineWidth()
);
}
if (d.imUlStroke != null) {
maxy = Math.max(
maxy,
trs.metrics.underlineOffset +
d.imUlStroke.getLineWidth() +
(d.imUlStroke2 == null ? 0 : d.imUlStroke2.getLineWidth())
);
}
}
return new Rectangle2D.Double(minx, miny, maxx-minx, maxy-miny);
}
/**
* Extends the outline of the text run segment to
* include text decorations.
* @param trs - text segment
* @param segmentOutline - outline of the undecorated text
* @param d - decoration
* @return extended outline
*/
static Shape extendOutline(
TextRunSegment trs,
Shape segmentOutline,
Decoration d
) {
if (d == null || !d.ulOn && d.imUlStroke == null && !d.strikeThrough) {
return segmentOutline; // Nothing to do
}
Area res = new Area(segmentOutline);
float left = (float) trs.getLogicalBounds().getMinX() - trs.x;
float right = (float) trs.getLogicalBounds().getMaxX() - trs.x;
d.getStrokes(trs.metrics);
if (d.strikeThrough) {
float y = trs.metrics.strikethroughOffset;
res.add(new Area(d.strikeThroughStroke.createStrokedShape(
new Line2D.Float(left, y, right, y)
)));
}
if (d.ulOn) {
float y = trs.metrics.underlineOffset;
res.add(new Area(d.ulStroke.createStrokedShape(
new Line2D.Float(left, y, right, y)
)));
}
if (d.imUlStroke != null) {
float y = trs.metrics.underlineOffset;
res.add(new Area(d.imUlStroke.createStrokedShape(
new Line2D.Float(left, y, right, y)
)));
if (d.imUlStroke2 != null) {
y++;
res.add(new Area(d.imUlStroke2.createStrokedShape(
new Line2D.Float(left, y, right, y)
)));
}
}
return res;
}
}