Java Primer Plus/Java Primer Plus (Waite Group Proess)(1996).iso/java_Win/demo/Fractal/CLSFractal.class

Java Class File | 1995-10-12 | 4.6 KB | 211 lines

import java.applet.Applet;
import java.awt.Component;
import java.awt.Event;
import java.awt.Graphics;
import java.util.Stack;

public class CLSFractal extends Applet implements Runnable {
   ContextLSystem cls;
   int fractLevel = 1;
   int repaintDelay = 50;
   boolean incrementalUpdates;
   float startAngle;
   float rotAngle;
   float Xmin;
   float Xmax;
   float Ymin;
   float Ymax;
   int border;
   boolean normalizescaling;
   Thread kicker;
   String savedPath;

   public void init() {
      this.cls = new ContextLSystem(this);
      String s = ((Applet)this).getParameter("level");
      if (s != null) {
         this.fractLevel = Integer.parseInt(s);
      }

      s = ((Applet)this).getParameter("incremental");
      if (s != null) {
         this.incrementalUpdates = s.equals("true");
      }

      s = ((Applet)this).getParameter("delay");
      if (s != null) {
         this.repaintDelay = Integer.parseInt(s);
      }

      s = ((Applet)this).getParameter("startAngle");
      if (s != null) {
         this.startAngle = Float.valueOf(s);
      }

      s = ((Applet)this).getParameter("rotAngle");
      if (s != null) {
         this.rotAngle = Float.valueOf(s);
      }

      this.rotAngle = this.rotAngle / 360.0F * 2.0F * (float)Math.PI;
      s = ((Applet)this).getParameter("border");
      if (s != null) {
         this.border = Integer.parseInt(s);
      }

      s = ((Applet)this).getParameter("normalizescale");
      if (s != null) {
         this.normalizescaling = s.equals("true");
      }

   }

   public void run() {
      Thread me = Thread.currentThread();
      boolean needsRepaint = false;

      while(this.kicker == me && this.cls.getLevel() < this.fractLevel) {
         this.cls.generate();
         if (this.kicker == me && this.incrementalUpdates) {
            ((Component)this).repaint();

            try {
               Thread.sleep((long)this.repaintDelay);
            } catch (InterruptedException var3) {
            }
         } else {
            needsRepaint = true;
         }
      }

      if (this.kicker == me) {
         this.kicker = null;
         if (needsRepaint) {
            ((Component)this).repaint();
         }
      }

   }

   public void start() {
      this.kicker = new Thread(this);
      this.kicker.start();
   }

   public void stop() {
      this.kicker = null;
   }

   public boolean mouseUp(Event evt, int x, int y) {
      this.cls = new ContextLSystem(this);
      this.savedPath = null;
      this.start();
      return true;
   }

   public void paint(Graphics g) {
      String fractalPath = this.cls.getPath();
      if (fractalPath == null) {
         super.paint(g);
      } else {
         if (this.savedPath == null || !this.savedPath.equals(fractalPath)) {
            this.savedPath = fractalPath;
            this.render((Graphics)null, fractalPath);
         }

         for(int i = 0; i < this.border; ++i) {
            g.draw3DRect(i, i, ((Component)this).size().width - i * 2, ((Component)this).size().height - i * 2, false);
         }

         this.render(g, fractalPath);
      }
   }

   void render(Graphics g, String path) {
      Stack turtleStack = new Stack();
      CLSTurtle turtle;
      if (g == null) {
         this.Xmin = 1.0E20F;
         this.Ymin = 1.0E20F;
         this.Xmax = -1.0E20F;
         this.Ymax = -1.0E20F;
         turtle = new CLSTurtle(this.startAngle, 0.0F, 0.0F, 0, 0, 1.0F, 1.0F);
      } else {
         float frwidth = this.Xmax - this.Xmin;
         if (frwidth == 0.0F) {
            frwidth = 1.0F;
         }

         float frheight = this.Ymax - this.Ymin;
         if (frheight == 0.0F) {
            frheight = 1.0F;
         }

         float xscale = (float)(((Component)this).size().width - this.border * 2 - 1) / frwidth;
         float yscale = (float)(((Component)this).size().height - this.border * 2 - 1) / frheight;
         int xoff = this.border;
         int yoff = this.border;
         if (this.normalizescaling) {
            if (xscale < yscale) {
               yoff = (int)((float)yoff + ((float)(((Component)this).size().height - this.border * 2) - (this.Ymax - this.Ymin) * xscale) / 2.0F);
               yscale = xscale;
            } else if (yscale < xscale) {
               xoff = (int)((float)xoff + ((float)(((Component)this).size().width - this.border * 2) - (this.Xmax - this.Xmin) * yscale) / 2.0F);
               xscale = yscale;
            }
         }

         turtle = new CLSTurtle(this.startAngle, -this.Xmin, -this.Ymin, xoff, yoff, xscale, yscale);
      }

      for(int pos = 0; pos < path.length(); ++pos) {
         switch (path.charAt(pos)) {
            case ']':
               turtle = (CLSTurtle)turtleStack.pop();
               break;
            case '[':
               turtleStack.push(turtle);
               turtle = new CLSTurtle(turtle);
               break;
            case 'F':
               if (g == null) {
                  this.includePt(turtle.X, turtle.Y);
                  turtle.jump();
                  this.includePt(turtle.X, turtle.Y);
               } else {
                  turtle.draw(g);
               }
               break;
            case '-':
               turtle.rotate(-this.rotAngle);
               break;
            case '+':
               turtle.rotate(this.rotAngle);
               break;
            case 'f':
               turtle.jump();
         }
      }

   }

   void includePt(float x, float y) {
      if (x < this.Xmin) {
         this.Xmin = x;
      }

      if (x > this.Xmax) {
         this.Xmax = x;
      }

      if (y < this.Ymin) {
         this.Ymin = y;
      }

      if (y > this.Ymax) {
         this.Ymax = y;
      }

   }
}