PenGestureListener.java

package edu.stanford.hci.r3.pen.gesture;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.Writer;
import java.util.ArrayList;

import edu.stanford.hci.r3.pen.PenSample;
import edu.stanford.hci.r3.pen.streaming.listeners.PenListener;

public class PenGestureListener implements PenListener {
        
        private ArrayList<Gesture> gestures = new ArrayList<Gesture>();

        private ArrayList<ShapeContext> contexts = new ArrayList<ShapeContext>();

        private ArrayList<PenSample> samples = null;

        private int gestureThreshold = 4;

        private int remainingContexts = 0;

        private GestureDatabase database;

        private String author;

        private static BufferedReader stdin = new BufferedReader(new InputStreamReader(System.in));

        public void penDown(PenSample sample) {
                samples = new ArrayList<PenSample>();
        }

        public void setContexts(ArrayList<ShapeContext> contexts, int remainingContexts) {
                this.contexts = contexts;
                this.remainingContexts = remainingContexts;
        }

        public void penUp(PenSample sample) {
                final double categoryThreshold = 20;
                if (samples != null && samples.size() > gestureThreshold && remainingContexts > 0) {
                        // normalize samples by first in space, maybe time
                        double min_x = Double.MAX_VALUE, min_y = Double.MAX_VALUE;
                        long min_t = Long.MAX_VALUE;
                        for (PenSample inksample : samples) {
                                min_x = Math.min(min_x, inksample.x);
                                min_y = Math.min(min_y, inksample.y);
                                min_t = Math.min(min_t, inksample.timestamp);
                        }
                        for (PenSample inksample : samples) {
                                inksample.x -= min_x;
                                inksample.y -= min_y;
                                inksample.timestamp -= min_t;
                        }
                        System.out.println("Gesture accepted.");
                        remainingContexts--;
                        int index = -1;
                        double distance = Double.MAX_VALUE;
                        ShapeContext context = new ShapeContext(samples, author);
                        contexts.add(context);
                        if (remainingContexts == 0)
                                System.out.println("Done reading gestures.");
                } else if (samples != null && samples.size() > gestureThreshold && database != null) {
                        ShapeContext context = new ShapeContext(samples, "");
                        database.test(context, true);
                }
                samples = null;
        }

        public void sample(PenSample sample) {
                PenSample inkSample = new PenSample(sample.x, sample.y, sample.force, sample.timestamp);
                samples.add(inkSample);
        }

        public void quillWrite(Writer writer) throws IOException {
                final String VERSION = "gdt 2.0";

                writer.write(VERSION + "\n");
                // gesture package
                String name = "bob";
                writer.write("name\t" + name + "\n");
                writer.write("training\n");
                // gesture set
                writer.write("name\t" + name + "\n");
                for (Gesture gesture : gestures) {
                        writer.write("category\n");
                        gesture.quillWrite(writer);
                }
                // end category
                writer.write("endset\n");
                // end set
                writer.write("test\n");
                writer.write("endpackage\n");
                writer.close();
        }

        public void setDatabase(GestureDatabase database) {
                // TODO Auto-generated method stub
                this.database = database;
        }

        public void setAuthor(String author) {
                // TODO Auto-generated method stub
                this.author = author;
        }
}

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