Note: you can sometimes better see a fold by flipping backwards and forwards
between diagrams.
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The code can be obtained here.
**********************/ /* An applet that draws lines and text * according to the coordinates in the html file. * - a little clunky, but does the job. * - Peter van der Linden, June 24 1996 * */ import java.awt.*; import java.applet.Applet; import java.io.*; import java.util.Hashtable; class Lines { //keeps a record of the lines we have read in // L1[i]..L4[i] holds all the lines on screen at fold i. static final int num_folds = 50; static final int lines_per_fold = 100; int [][] L1 = new int[num_folds][lines_per_fold]; int [][] L2 = new int[num_folds][lines_per_fold]; int [][] L3 = new int[num_folds][lines_per_fold]; int [][] L4 = new int[num_folds][lines_per_fold]; int i = 0; void store_lines(int fold, int w, int x, int y, int z) { for (i = 0; i < L1.length; i++) if (L1[fold][i] == 0) break; L1[fold][i] = w; L2[fold][i] = x; L3[fold][i] = y; L4[fold][i] = z; //System.out.println("Storing [" + i + "] " + w + "," + x); } } class namedLine { // gives a name to the line between x1,y1 and xy,y2 int x1,y1,x2,y2; } public class f2 extends Applet { Panel p = new Panel(); Button bp = new Button("previous"); Button bn = new Button("start"); int j = 0, curr_fold = 0; String s, w; StringBufferInputStream sbis; StreamTokenizer st; Lines L = new Lines(); static final int named_points = 100; Hashtable H = new Hashtable(named_points); public void init() { p.resize(100, 40); //put the "previous" button on a panel p.add(bp); //that isn't displayed at first. p.setBackground(Color.yellow); add(p); p.hide(); add(bn); setForeground(Color.blue); // blue on yellow gives excellent contrast setBackground(Color.yellow); } public void paint(Graphics g) { if (w != null) g.drawString("Step " + curr_fold + ": " + w, 35, 50); //draw all the stored lines for this fold int i = 0; while (L.L1[curr_fold][i] != 0) { g.drawLine(L.L1[curr_fold][i], L.L2[curr_fold][i], L.L3[curr_fold][i], L.L4[curr_fold][i++]); } } public boolean action(Event e, Object o) { if (e.target instanceof Button) { if ("next".equals((String) o)) curr_fold++; else if ("start".equals((String) o)) { bn.setLabel("next"); curr_fold = 1; p.show(); p.validate(); } else if (curr_fold > 1) curr_fold--; if (L.L1[curr_fold][0] == 0) { //need to read in lines s = getParameter("fold" + curr_fold); if (s == null) { curr_fold--; return true; } sbis = new StringBufferInputStream(s); st = new StreamTokenizer(sbis); st.parseNumbers(); int c, w, x, y, z; try { while ((c = st.nextToken()) != st.TT_EOF) { if ( c==st.TT_NUMBER) { w = (int) st.nval; c = st.nextToken(); x = (int) st.nval; c = st.nextToken(); y = (int) st.nval; c = st.nextToken(); z = (int) st.nval; L.store_lines(curr_fold, w, x, y, z); } else { // TT_WORD s = st.sval; // get the word //look it up in the hashtable namedLine nl = (namedLine) H.get(s); if (nl==null) { //if not in hash table, add it. nl = new namedLine(); c = st.nextToken(); nl.x1 = (int) st.nval; c = st.nextToken(); nl.y1 = (int) st.nval; c = st.nextToken(); nl.x2 = (int) st.nval; c = st.nextToken(); nl.y2 = (int) st.nval; try{H.put(s, nl);} catch(NullPointerException npe){System.out.println("point name is null");} } // now store the coords in the fold L.store_lines(curr_fold, nl.x1,nl.y1,nl.x2,nl.y2); } } } catch(IOException ioe) { ioe.printStackTrace(); return true; } } w = getParameter("words" + curr_fold); repaint(); return true; } return false; } }
