org.nfunk.jepexamples.FractalCanvas Maven / Gradle / Ivy
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/*****************************************************************************
JEP 2.4.1, Extensions 1.1.1
April 30 2007
(c) Copyright 2007, Nathan Funk and Richard Morris
See LICENSE-*.txt for license information.
*****************************************************************************/
package org.nfunk.jepexamples;
import java.awt.*;
import java.util.*;
import org.nfunk.jep.*;
import org.nfunk.jep.type.*;
import org.nfunk.jep.evaluation.*;
/**
* This class performs the drawing of the fractal.
*/
public class FractalCanvas extends Canvas {
private static final long serialVersionUID = -593341831485283712L;
private int scaleX, scaleY;
private Dimension dimensions;
private int iterations, nEvals;
private boolean hasError;
private JEP myParser;
private ExpressionCompiler expressionCompiler;
private CommandEvaluator evaluator;
private CommandElement[] commands;
private SymbolTable symTab;
private java.awt.TextField exprField;
/**
* Constructor.
*/
public FractalCanvas(String initialExpression, java.awt.TextField exprField_in) {
iterations = 20;
nEvals = 0;
scaleX = 100;
scaleY = 100;
dimensions = getSize();
hasError = true;
exprField = exprField_in;
initParser(initialExpression);
expressionCompiler = new ExpressionCompiler();
evaluator = new CommandEvaluator();
symTab = myParser.getSymbolTable();
}
/**
* Initializes the parser
*/
private void initParser(String initialExpression) {
//Init Parser
myParser = new JEP();
//Load the standard functions
myParser.addStandardFunctions();
//Load the standard
myParser.addStandardConstants();
myParser.addComplex();
//Add and initialize z to (0,0)
myParser.addVariable("z",0,0);
myParser.addVariable("c",0,0);
setExpressionString(initialExpression);
}
/**
* Parses a new expression
*/
public void setExpressionString(String newString) {
nEvals = 0;
//Parse the new expression
myParser.parseExpression(newString);
//Find out whether there was an error in the expression
hasError = myParser.hasError();
if (hasError)
exprField.setForeground(Color.red);
else
exprField.setForeground(Color.black);
}
public void setIterations(int iterations_in) {
iterations = iterations_in;
}
private void paintWhite(Graphics g) {
g.setColor(Color.white);
g.fillRect(0,0,dimensions.width,dimensions.height);
}
private void paintFractalSansJEP(Graphics g) {
System.out.println("paintFractalSansJEP()");
//paintRegion(g, 0,0,256,256,0,8);
System.out.println("done.");
}
private void paintRegion(Graphics g, int x, int y,
int width, int height, int depth,
int depth_max) {
double re, im, p, q, resq, imsq, imtemp;
int count;
if (depth == depth_max) {
p = (double)(x+width/2-230)/scaleX;
q = (double)(y+height/2-150)/scaleY;
count = 0;
re = 0;
im = 0;
resq = 0;
imsq = 0;
while ((count < iterations) && ((resq + imsq) < 4.0)) {
imtemp = 2 * re * im;
re = resq - imsq + p;
im = imtemp + q;
count++;
resq = re * re;
imsq = im * im;
nEvals++;
}
//System.out.println("At: " + x + ", " + y + ": " + count + " "+ result);
if (count != iterations) {
g.setColor(new Color(0, 0, (int)(255.0*(Math.sqrt(count)/Math.sqrt(iterations)))));
g.fillRect(x, y, width, height);
}
} else {
paintRegion(g, x, y, width/2, height - height/2, depth+1, depth_max);
paintRegion(g, x + width/2, y, width - width/2, height/2, depth+1, depth_max);
paintRegion(g, x, y + height/2, width/2, height - height/2, depth+1, depth_max);
paintRegion(g, x + width/2, y + height/2, width - width/2, height - height/2, depth+1, depth_max);
}
}
private void paintFractal(Graphics g) {
Complex z,c,temp;
int count;
c = myParser.addVariable("c", 0, 0);
z = myParser.addVariable("z", 0, 0);
for (int x = 0; x <= (dimensions.width-1); x++) {
for (int y = 0; y <= (dimensions.height-1); y++) {
count = 0;
c.set((double)(x-230)/scaleX,
(double)(y-150)/scaleY);
z.set(0,0);
while ((count < iterations) && (z.abs2() < 4.0)) {
z.set(myParser.getComplexValue());
count++;
nEvals++;
}
if (count != iterations) {
g.setColor(new Color(0, 0, (int)(255.0*(Math.sqrt(count)/Math.sqrt(iterations)))));
g.fillRect(x, y, 1, 1);
}
}
}
}
private void paintFractalWithCompiler(Graphics g) {
Complex z,c,temp;
int count;
c = myParser.addVariable("c", 0, 0);
z = myParser.addVariable("z", 0, 0);
try {
commands = expressionCompiler.compile(myParser.getTopNode());
} catch (ParseException e) {
System.out.println("Failed to compile expression");
e.printStackTrace();
}
for (int x = 0; x <= (dimensions.width-1); x++) {
for (int y = 0; y <= (dimensions.height-1); y++) {
count = 0;
c.set((double)(x-230)/scaleX,
(double)(y-150)/scaleY);
z.set(0,0);
while ((count < iterations) && (z.abs2() < 4.0)) {
try {
temp = (Complex)evaluator.evaluate(commands, symTab);
z.set(temp);
} catch (Exception e) {
//System.out.println(e.toString());
e.printStackTrace();
}
count++;
nEvals++;
}
if (count != iterations) {
g.setColor(new Color(0, 0, (int)(255.0*(Math.sqrt(count)/Math.sqrt(iterations)))));
g.fillRect(x, y, 1, 1);
}
}
}
}
private void paintNonJEPFractal(Graphics g) {
double re, im, p, q, resq, imsq, imtemp;
int count;
for (int x = 0; x <= (dimensions.width-1); x++) {
for (int y = 0; y <= (dimensions.height-1); y++) {
p = (double)(x-230)/scaleX;
q = (double)(y-150)/scaleY;
count = 0;
re = 0;
im = 0;
resq = 0;
imsq = 0;
while ( (count < iterations) && ((resq + imsq) < 4.0) ) {
imtemp = 2 * re * im;
re = resq - imsq + p;
im = imtemp + q;
resq = re * re;
imsq = im * im;
count++;
nEvals++;
}
//System.out.println("At: " + x + ", " + y + ": " + count + " "+ result);
if (count != iterations) {
g.setColor(new Color(0, 0, (int)(255.0*(Math.sqrt(count)/Math.sqrt(iterations)))));
g.fillRect(x, y, 1, 1);
}
}
}
}
public void paint(Graphics g) {
Date start, finish;
dimensions = getSize();
paintWhite(g);
if (!hasError) {
System.out.println("Painting... ");
start = new Date();
nEvals = 0;
//paintFractal(g);
paintFractalWithCompiler(g);
//paintNonJEPFractal(g);
finish = new Date();
System.out.print("done. sec/eval: ");
double seconds = ( finish.getTime() - start.getTime() ) / 1000.0;
System.out.println(seconds/nEvals);
}
/*
if (!initializedBuffer)
{
buffer = createImage(dimensions.width, dimensions.height);
initializedBuffer = true;
}
Graphics buffergc = buffer.getGraphics();
if (changedFunction)
{
paintWhite(buffergc);
if (!hasError) paintFractal(buffergc);
g.drawImage(buffer, 0, 0, null);
changedFunction = false;
}
else
{
g.drawImage(buffer, 0, 0, null);
}*/
}
}