package com.bbn.openmap.omGraphics.awt;
import java.awt.Font;
import java.awt.FontMetrics;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.geom.AffineTransform;
import java.awt.geom.Point2D;
import java.awt.image.BufferedImage;
import java.util.LinkedList;
/**
* A ShapeDecoration that draws a text along a path
*
* @author Eric LEPICIER
* @version 16 aot 2002
*/
public class TextShapeDecoration
extends AbstractShapeDecoration {
private String text;
private Font font = null;
private int verticalAlignment = BASELINE;
/** Baseline vertical alignment */
public final static int BASELINE = 1;
/** Center vertical alignment */
public final static int CENTER = 2;
/** Top vertical alignment */
public final static int TOP = 3;
/** Bottom vertical alignment */
public final static int BOTTOM = 4;
/** Orientation for the shape text decoration: use poly direction */
public final static int FORWARD = LEFT;
/**
* Orientation for the shape text decoration: use reverse poly direction
*/
public final static int BACKWARD = RIGHT;
/** Orientation for the shape text decoration: force left to right */
public final static int LEFT_TO_RIGHT = 3;
/** Orientation for the shape text decoration: force right to left */
public final static int RIGHT_TO_LEFT = 4;
/** Orientation for the shape text decoration: force top to bottom */
public final static int TOP_TO_BOTTOM = 5;
/** Orientation for the shape text decoration: force bottom to top */
public final static int BOTTOM_TO_TOP = 6;
/**
* Orientation for the shape text decoration: occidental reading use
*/
public final static int MOST_READABLE = 7;
/**
* Text will follow the poly instead of being written on the segment from
* begin to end of the poly, also allow text to be uncomplete. You may add
* this one to the other constants
*/
public final static int FOLLOW_POLY = 16;
private transient FontMetrics metrics;
private transient Graphics2D g2D = null;
/**
* Constructor.
*
* @param text
* @param font
* @param orientation
* @param verticalAlignment
*/
public TextShapeDecoration(String text, Font font, int orientation, int verticalAlignment) {
super(0.0f, 0.0f, orientation);
setVerticalAlignment(verticalAlignment);
setFont(font);
setText(text);
initMetrics();
}
/**
* Constructor.
*
* @param text
*/
public TextShapeDecoration(String text) {
super(0.0f, 0.0f, FORWARD);
setVerticalAlignment(BASELINE);
setText(text);
initMetrics();
}
/**
* init Metrics used to get string graphic length.
*
* @param object
*/
private void initMetrics() {
if (g2D == null)
g2D = (Graphics2D) new BufferedImage(10, 10, BufferedImage.TYPE_INT_RGB).getGraphics();
if (font == null)
font = g2D.getFont();
metrics = g2D.getFontMetrics(font);
}
/**
* Draws the text along the polyline
*
* @see com.bbn.openmap.omGraphics.awt.ShapeDecoration#draw(Graphics,
* Point2D[], boolean)
*/
public void draw(Graphics g, Point2D[] points, boolean complete) {
g2D = (Graphics2D) g;
initMetrics();
g.setFont(font);
int x1 = (int) points[0].getX();
int y1 = (int) points[0].getY();
int x2 = (int) points[points.length - 1].getX();
int y2 = (int) points[points.length - 1].getY();
boolean reverse = needToReverse(x1, y1, x2, y2);
// draw the text exactly on the curve, even uncomplete
if ((getOrientation() & FOLLOW_POLY) > 0) {
drawFollow(g, points, reverse);
return;
}
// if there's not enough room, do nothing
if (!complete)
return;
// else plot the text straight on the half segment
// from start to end point and away
int x, y;
double angle;
if (reverse) {
x = x2;
y = y2;
angle = Math.atan2(y1 - y2, x1 - x2);
} else {
x = x1;
y = y1;
angle = Math.atan2(y2 - y1, x2 - x1);
}
// adjust vertical alignment
switch (verticalAlignment) {
case TOP:
y += metrics.getAscent();
break;
case BOTTOM:
y -= metrics.getDescent();
break;
case CENTER:
y += metrics.getAscent() - (metrics.getHeight()) / 2;
break;
case BASELINE:
break;
}
drawAngledString(g, text, x, y, angle);
}
/**
* Returns true if the polyline need to be reverted for the text to be drawn
* with the specified orientation.
*
* @param x1 starting point x coordinate
* @param y1 starting point y coordinate
* @param x2 ending point x coordinate
* @param y2 ending point y coordinate
* @return boolean
*/
protected boolean needToReverse(int x1, int y1, int x2, int y2) {
boolean reverse = false;
switch (getOrientation() & ~FOLLOW_POLY) {
case FORWARD:
break;
case BACKWARD:
reverse = true;
break;
case LEFT_TO_RIGHT:
reverse = x1 > x2;
break;
case RIGHT_TO_LEFT:
reverse = x1 < x2;
break;
case TOP_TO_BOTTOM:
reverse = y1 > y2;
break;
case BOTTOM_TO_TOP:
reverse = y1 < y2;
break;
case MOST_READABLE:
reverse = x2 < x1 || y1 > y2;
break;
}
return reverse;
}
/**
* Draws the text character per character to follow the polyline
*
* @param g
* @param pts
* @param reverse
*/
protected void drawFollow(Graphics g, Point2D[] pts, boolean reverse) {
LinkedList points = new LinkedList();
if (reverse) {
for (int i = pts.length - 1; i >= 0; i--)
points.add(pts[i]);
} else {
for (int i = 0; i < pts.length; i++)
points.add(pts[i]);
}
LinkedList polysegment = new LinkedList();
int l, x1, y1, x2, y2;
String c;
Point2D p1, p2;
double angle;
for (int i = 0; i < text.length(); i++) {
c = text.substring(i, i + 1);
l = metrics.stringWidth(c);
if (points.isEmpty())
break;
LineUtil.retrievePoints(l, points, polysegment);
p1 = (Point2D) polysegment.getFirst();
x1 = (int) p1.getX();
y1 = (int) p1.getY();
p2 = (Point2D) polysegment.getLast();
x2 = (int) p2.getX();
y2 = (int) p2.getY();
angle = Math.atan2(y2 - y1, x2 - x1);
drawAngledString(g, c, x1, y1, angle);
}
}
/**
* Draws the text from a starting point with an angle
*
* @param g
* @param text
* @param x
* @param y
* @param angle
*/
public static void drawAngledString(Graphics g, String text, int x, int y, double angle) {
Graphics2D g2D = (Graphics2D) g;
AffineTransform oldAt = g2D.getTransform();
AffineTransform at = new AffineTransform(oldAt);
at.rotate(angle, x, y);
g2D.setTransform(at);
g2D.drawString(text, x, y);
g2D.setTransform(oldAt);
}
/**
* Returns the font.
*
* @return Font
*/
public Font getFont() {
return font;
}
/**
* Returns the text.
*
* @return String
*/
public String getText() {
return text;
}
/**
* Sets the font.
*
* @param font The font to set
*/
public void setFont(Font font) {
this.font = font;
initMetrics();
}
/**
* Sets the text.
*
* @param text The text to set
*/
public void setText(String text) {
this.text = text;
initMetrics();
setLength(metrics.stringWidth(text));
setWidth(metrics.getHeight());
}
/**
* Returns the verticalAlignment.
*
* @return int
*/
public int getVerticalAlignment() {
return verticalAlignment;
}
/**
* Sets the verticalAlignment.
*
* @param verticalAlignment The verticalAlignment to set (TOP, CENTER,
* BASELINE, BOTTOM)
*/
public void setVerticalAlignment(int verticalAlignment) {
this.verticalAlignment = verticalAlignment;
}
}