gzz-mirror/Java/flob/FTextLayouter.zob

/*   
FTextLayouter.java
 *    
 *    Copyright (c) 1999-2000, Ted Nelson and Tuomas Lukka
 *
 *    You may use and distribute under the terms of either the GNU Lesser
 *    General Public License, either version 2 of the license or,
 *    at your choice, any later version. Alternatively, you may use and
 *    distribute under the terms of the XPL.
 *
 *    See the LICENSE.lgpl and LICENSE.xpl files for the specific terms of 
 *    the licenses.
 *
 *    This software is distributed in the hope that it will be useful,
 *    but WITHOUT ANY WARRANTY; without even the implied warranty of
 *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the README
 *    file for more details.
 *
 */
/*
 * Written by Benjamin Fallenstein
 */
 
package org.gzigzag;
import java.awt.*;
import java.awt.event.*;
import java.util.*;

/** A layouter for flowing formatted text in a fixed-width rectangle.
 * @see FText
 */

public class FTextLayouter implements ZOb {
public static final String rcsid = "$Id: FTextLayouter.zob,v 1.10 2001/03/30 16:19:37 bfallenstein Exp $";
    public static boolean dbg = false;
    static final void p(String s) { if(dbg) System.out.println(s); }
    static final void pa(String s) { System.out.println(s); }

    public FTextLayouter() {}
    public FTextLayouter(boolean firstCap) { this.firstCap = firstCap; }

    STRUCTPARAMS {
	/** Capitalize any letter after two spaces.
	 * This allows simple rearrangement of text without having
	 * to think about capitalization at all times by ending
	 * each sentence with the period/question/... and two spaces.
	 * XXX Maybe this shouldn't be here after all - maybe
	 * separate FText.Part firstcap completely from rendering
	 * to a separate call??
	 */
	boolean firstCap
	    = true;

    }

    /** (Internal convenience) Place a number of lines from an array,
     * given first and last line.
     */
    void placeLines(FlobSet into,
		    FText.Part[][] lines, 
		    int[] heights,
		    Rectangle rect,
		    int first, 
		    int last, 
		    int depth,
		    boolean cursors,
		    Flob fparent) {
	int y = rect.y, maxx = rect.x + rect.width;
	p("FTextLayouter placeLines first "+first+" last "+last+" length "+lines.length);

	Renderable prev = null;
	for(int linenr=first; linenr<=last; linenr++) {
	    FText.Part[] line = lines[linenr];
	    int x = rect.x;
	    y += heights[linenr];

	    for(int partnr = 0; partnr<line.length; partnr++) {
		FText.Part part = line[partnr];
		int h = part.height(), w = part.width();
		
		prev = part.rend(x, y-h, depth, prev);
		if(prev instanceof SplitCellFlob1) {
		    SplitCellFlob1 cur = (SplitCellFlob1)prev;
		    if(cursors) addCurs(into, cur);
		    cur.fg = part.fg; // makes them depth-aware if part.fg is null
		}
		if(into!=null) {
		    if(prev instanceof Flob) {
			Flob f = (Flob)prev;
			if(fparent != null) f.setParent(fparent);
			if(f.x + f.w > rect.x + rect.width) {
			    p("FTL clip: "+f.x+" "+f.w+" in "+rect.x+" "+rect.width+" at "+f.c);
			    f.w = rect.x + rect.width - f.x;
			    if(f instanceof SplitCellFlob1)
				((SplitCellFlob1)f).doClip = true;
			}
			if(f.w < 0) f.w = 0;
		    }
		    into.add(prev);
		}

		x += w;
		if(x > maxx) break;
	    }
	}
    }

    /** (Internal convenience) Find the correct span of lines to layout.
     *  Returns an array with two ints: the last line number and the height.
     */
    int[] layout(FText.Part[][] lines, 
		 int[] heights,
		 int start, 
		 int dir,
		 int maxh) {
	int height = 0, i = start;
	for(; i>=0 && i<lines.length; i+=dir) {
	    int lineh = FText.Part.height(lines[i]);
	    heights[i] = lineh;
	    if(height + lineh > maxh) return new int[] { i-dir, height };
	    height += lineh;
	}
	return new int[] { i-dir, height };
    }
	

    public Rectangle place(FlobSet into, FText txt, Rectangle rect,
			    int direction, int initY,
			     int middleoffs, 
			     boolean cursors) {
	return place(into, txt, rect, 100, 
			direction, initY, middleoffs, cursors, (Flob)null);
    }

    /** To be deprecated -- DON'T USE! */
    public Rectangle place(FlobSet into, FText txt, Rectangle rect,
			    int direction, int initY,
			     int middleoffs, 
			     boolean cursors,
			     boolean[] beginningSentence) {
	return place(into, txt, rect, 100, 
			direction, initY, middleoffs, cursors, (Flob)null);
    }

    /** To be deprecated -- DON'T USE! */
    public Rectangle place(FlobSet into, FText txt, Rectangle rect,
			     int depth,
			    int direction, int initY,
			     int middleoffs, 
			     boolean cursors,
			     boolean[] beginningSentence) {
	return place(into, txt, rect, depth, 
			direction, initY, middleoffs, cursors, (Flob)null);
    }

    public Rectangle place(FlobSet into, FText txt, Rectangle rect,
			     int depth,
			    int direction, int initY,
			     int middleoffs, 
			     boolean cursors) {
	return place(into, txt, rect, depth,
			direction, initY, middleoffs, cursors, (Flob)null);
    }

    /** Place a piece of formatted text into a fixed-width rectangle.
     * @param into The flobset to place the text into.
     * @param txt The formatted text object
     * @param rect The rectangle to fit things into. This is used for
     *		  both stopping rendering at the upper and lower edges
     *		  and for the margin widths.
     *		  (XXX How to i18nize this for other directions?!?!)
     * @param depth	The depth at which to place the flobs.
     * @param direction The direction we're moving.
     *			0 = starting from the middle of a paragraph,
     *			1 = down, -1 = up
     * @param initY	The y coordinate to place the middle/first/last line
     *			of text at, depending on direction.
     * @param middleoffs If direction==0, the offset that should be at initY.
     * @param cursors	Whether to draw cursors.
     * @param fparent   The flob parent.
     */
    public Rectangle place(FlobSet into, FText txt, Rectangle rect,
			     int depth,
			    int direction, int initY,
			     int middleoffs, 
			     boolean cursors,
			     Flob fparent) {
	if(firstCap) txt.capitalize();
	FText.Part[][] lines = txt.getLines(rect.width);
	if(lines.length == 0) 
	    return new Rectangle(rect.x, initY, rect.width, 0);
	
	/** The height of each line. */
	int[] heights = new int[lines.length];
	
	/** The first and last lines to place. */
	int first, last;
	
	Rectangle res;
	
	if(direction < 0) {
	    last = lines.length-1;
	    int[] lay = layout(lines, heights, last, -1,
			       initY-rect.y);


	    first = lay[0]; last = lines.length-1;
	    res = new Rectangle(rect.x, initY-lay[1], rect.width, lay[1]);
	} else if(direction > 0) {
	    first = 0;
	    int[] lay = layout(lines, heights, first, 1, 
			       rect.y + rect.height - initY);
	    last = lay[0];
	    res = new Rectangle(rect.x, initY, rect.width, lay[1]);
	} else {
	    int middle = FText.findLine(lines, middleoffs);
	    // Make it the middle of the middle line.
	    initY -= FText.Part.height(lines[middle])/2;
	
	    int[] lay1 = layout(lines, heights, middle-1, -1,
				rect.y + rect.height - initY);
	    int[] lay2 = layout(lines, heights, middle, 1, initY-rect.y);
	
	    first = lay1[0]; last = lay2[0];
	    res = new Rectangle(rect.x, initY-lay1[1], rect.width,
				lay1[1]+lay2[1]);
	}
	
	placeLines(into, lines, heights, res, first, last, depth, 
		   cursors, fparent);
	return res;
    }

    // XXX make more efficient: do cursor search only for parent sf
    public static void addCurs(FlobSet into, SplitCellFlob1 sf) {

	Enumeration e = ZZCursorReal.getPointers(sf.getCell());
	while(e.hasMoreElements()) {
	    ZZCell c = (ZZCell)e.nextElement();

	    int ind = ZZCursorReal.getOffs(c);
	    if(ind == ZZCursorReal.NO_OFFSET) continue;
	    if(!(ind >= sf.start && ind <= sf.start + sf.n))
		continue;
	    int x = sf.getStrX(ind);
	    if(x >= 0 && into != null)
		into.add(new LineDecor(x, sf.y, x, sf.y+sf.h, 
			 Color.black, sf.d));
	} 
    }
}

// vim: set syntax=java :