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StackOverflowError when using Flood Fill Algorithm

I'm trying to implement flood fill algorithm using to fill the closed shape with specific color.
I think my code is worked out, but i don't know why are"StackOverflowError" rising up !!
i looked for the solution more and more but without finding the perfect answer.
public void paintComponent(Graphics g){
indecies.clear();
float x1 = 20;
float y1 = 20;
float x2 = 350;
float y2 = 20;
/* put the points of first line in ArraList */
for(int i = (int) x1; i < x2 ; i++){
index = (int) (i + y1 * img.getWidth());
list.add(index);
}
/***************************************************/
x1 = 350;
y1 = 20;
x2 = 100;
y2 = 100;
/* put the points of second line in ArraList */
for(int i = (int) y1; i <= y2 ; i++){
index = (int) (x1 * img.getWidth());
list.add(index);
}
/***************************************************/
x1 = 100;
y1 = 100;
x2 = 20;
y2 = 100;
/* put the points of the third line in ArraList */
for(int i = (int) x2; i < x1 ; i++){
index = (int) (i + y1 * img.getWidth());
list.add(index);
}
/*****************************************************/
x1 = 20;
y1 = 100;
x2 = 20;
y2 = 20;
/* put the points of the forth line in ArraList */
for(int i = (int) y2; i < y1 ; i++){
index = (int) (x1 * img.getWidth());
list.add(index);
}
/**************************************************/
/* Get each pixel from ArrayList of indecies then print into data raster of image */
for (Integer integer : indecies) {
pixels[integer] = Color.yellow.getRGB();
}
/* Flood fill recursive algorithm */
/* border color is yellow */
/* green is the new colow must be filled inside the shape */
fill(50, 50, Color.yellow.getRGB(), Color.green.getRGB());
g.drawImage(img, 0, 0, this);
}
Here is the fill method !!
public void fill(int x, int y, int borderColor, int newColor){
if(x >= 0 && x < width && y >= 0 && y < height){
int index = x + y * width;
if(pixels[index] != borderColor && pixels[index] != newColor){
pixels[index] = newColor;
fill(x, y - 1, borderColor, newColor);
fill(x, y + 1, borderColor, newColor);
fill(x + 1, y, borderColor, newColor);
fill(x - 1, y, borderColor, newColor);
}
}
}
Exception Details ..
java.lang.StackOverflowErrorjava.lang.StackOverflowErrorjava.lang.StackOverflowErrorjava.lang.StackOverflowErrorjava.lang.StackOverflowErrorjava.lang.StackOverflowError
at java.nio.Buffer.limit(Buffer.java:274)
at java.nio.Buffer.<init>(Buffer.java:201)
at java.nio.CharBuffer.<init>(CharBuffer.java:281)
at java.nio.HeapCharBuffer.<init>(HeapCharBuffer.java:70)
at java.nio.CharBuffer.wrap(CharBuffer.java:373)
at sun.nio.cs.StreamEncoder.implWrite(StreamEncoder.java:265)
at sun.nio.cs.StreamEncoder.write(StreamEncoder.java:125)
at java.io.OutputStreamWriter.write(OutputStreamWriter.java:207)
at java.io.BufferedWriter.flushBuffer(BufferedWriter.java:129)
at java.io.PrintStream.write(PrintStream.java:526)
at java.io.PrintStream.print(PrintStream.java:669)
at java.io.PrintStream.println(PrintStream.java:823)
at java.lang.Throwable$WrappedPrintStream.println(Throwable.java:748)
at java.lang.Throwable.printStackTrace(Throwable.java:655)
at java.lang.Throwable.printStackTrace(Throwable.java:643)
at java.lang.Throwable.printStackTrace(Throwable.java:634)
at FillColorAlgorithm.fill(FillColorAlgorithm.java:170)
at FillColorAlgorithm.fill(FillColorAlgorithm.java:162)
......... etc

public void floodFill(int x, int y, int borderColor, int fillColor, int imgWidth, int imgHeight){
Queue<java.awt.Point> nodesList = new LinkedList<>();
if(borderColor == fillColor) return;
if(x >= 0 && x < imgWidth && y >= 0 && y < imgHeight){
int index = x + y * imgWidth;
if(pixels[index] == fillColor) return;
nodesList.add(new java.awt.Point(x, y));
}
while(!nodesList.isEmpty()) {
java.awt.Point currentNode = nodesList.element();
int index = currentNode.x + currentNode.y * imgWidth;
if(pixels[index] != fillColor){
java.awt.Point westNode = currentNode;
java.awt.Point eastNode = currentNode;
westNode = MoveWest(westNode, borderColor);
eastNode = MoveEast(eastNode, borderColor);
for (int j = westNode.x + 1; j < eastNode.x; j++) {
index = j + currentNode.y * imgWidth;
pixels[index] = fillColor;
java.awt.Point northNode = new java.awt.Point(j, currentNode.y - 1);
java.awt.Point southNode = new java.awt.Point(j, currentNode.y + 1);
index = northNode.x + northNode.y * imgWidth;
if(northNode.y >= 0 && pixels[index] != fillColor && pixels[index] != borderColor) nodesList.add(northNode);
index = southNode.x + southNode.y * imgWidth;
if(southNode.y < imgHeight && pixels[index] != fillColor && pixels[index] != borderColor) nodesList.add(southNode);
}
}
nodesList.remove();
}
}
java.awt.Point MoveWest(java.awt.Point w, int borderColor){
int index;
do{
--w.x;
index = w.x + w.y * width;
}
while(w.x >= 0 && pixels[index] != borderColor);
return new java.awt.Point(w.x, w.y);
}
java.awt.Point MoveEast(java.awt.Point e, int borderColor){
int index;
do{
++e.x;
index = e.x + e.y * width;
}
while( e.x < width && pixels[index] != borderColor);
return new java.awt.Point(e.x, e.y);
}

How to make a Bresenham's line algorithm?

I wrote a small program, that draws a line from user inputs x1,y1 and x2,y2. For some reason line only works while horizontal, but once line should be vertical, it just shows me a black pixel not a line. I have checked everything and I am pretty sure that I got the algorithm right, but problem is still here.
int x1 = Integer.parseInt(this.jTextFieldX1.getText());
int y1 = Integer.parseInt(this.jTextFieldY1.getText());
int x2 = Integer.parseInt(this.jTextFieldX2.getText());
int y2 = Integer.parseInt(this.jTextFieldY2.getText());
int xi = x2 > x1 ? 1:-1;
int yi = y2 > y1 ? 1:-1;
int dx = Math.abs(x2-x1);
int dy = Math.abs(y2-y1);
int xn= x1;
int yn= y1;
int pn;
canvas.showBlackPixel(xn,yn);
if (dx > dy)
{
pn= 2*dy - dx;
while (xn != x2)
{
if (pn >0)
{
xn=xn + xi;
yn=yn + yi;
pn=pn + 2*dy - 2*dx;
}
else
{
xn = xn + xi;
pn = pn+ 2*dy;
}
canvas.showBlackPixel(xn,yn);
}
{
if (dy > dx)
{
pn= 2*dx - dy;
while (yn != y2)
{
if (pn > 0)
{
xn=xn + xi;
yn=yn + yi;
pn=pn + 2*dx - 2*dy;
}
else
{
yn = yn + yi;
pn = pn + 2*dx;
}
canvas.showBlackPixel(xn,yn);
}
}
}
}
}
How could I fix it?

The problem is with the termination of your statements, which is to say your braces {} are mixed up a little. To be specific, cut down to the relevant bits your code is:
if (dx > dy)
{
...
if (dy > dx)
{
...
}
}
If you fix your braces, then it looks like it should work better.
if (dx > dy)
{
...
}
if (dy > dx)
{
...
}
You'll still have an issue when dx == dy though.

Redrawing graph with new inputs, java graphics

I've been trying for hours to find the solution but with no results, so I have nowhere else to turn. I have a program that gathers data from user input and uses it to draw a graph. Every time the user changes the data in the text fields and presses submit I want a new graph drawn and get rid of the old one.
Currently nothing happens with the graph when I press submit with new inputs even though the inputs do change in both classes. For debugging purposes I had a
System.out.println(graphPoints.size());
in my DrawComponent class. I noticed that for everytime I press submit the amount of times graphPoints.size() gets printed out increases with one, so I assume thats no good. I really dont know where to go from here though.
Here is my actionlistener where I call the GraphPanel class:
query.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent arg0) {
textarea1.setText("");
textarea1.append(run(tickerInput,tickerInput2,startInput,slutInput,valuta));
Mainpanel.repaint();
if(testx != null)
testx.removeAll();
testx = new GraphPanel(first,second);
addItem(Mainpanel, testx, 0,20, 20,20, GridBagConstraints.SOUTH);
minframe.setVisible(true);
minframe.repaint();
minframe.pack();
testx.repaint();
And here is my GraphPanel class:
public GraphPanel(ArrayList<Double> first, ArrayList<Double> second) {
first1 = first;
Collections.reverse(first1);
second1 = second;
Collections.reverse(second1);
}
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
Graphics2D g2 = (Graphics2D) g;
g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
double xScale = ((double) getWidth() - (2 * padding) - labelPadding) / (first1.size() - 1);
double yScale = ((double) getHeight() - 2 * padding - labelPadding) / (getMaxScore() - getMinScore());
ArrayList<Point> graphPoints = new ArrayList<>();
for (int i = 0; i < first1.size(); i++) {
int x1 = (int) (i * xScale + padding + labelPadding);
int y1 = (int) ((getMaxScore() - first1.get(i)) * yScale + padding);
graphPoints.add(new Point(x1, y1));
}
ArrayList<Point> graphPoints2 = new ArrayList<>();
graphPoints2.clear();
for (int i = 0; i < second1.size(); i++) {
int x1 = (int) (i * xScale + padding + labelPadding);
int y1 = (int) ((getMaxScore() - second1.get(i)) * yScale + padding);
graphPoints2.add(new Point(x1, y1));
}
g2.setColor(Color.WHITE);
g2.fillRect(padding + labelPadding, padding, getWidth() - (2 * padding) - labelPadding, getHeight() - 2 * padding - labelPadding);
g2.setColor(Color.BLACK);
for (int i = 0; i < numberYDivisions + 1; i++) {
int x0 = padding + labelPadding;
int x1 = pointWidth + padding + labelPadding;
int y0 = getHeight() - ((i * (getHeight() - padding * 2 - labelPadding)) / numberYDivisions + padding + labelPadding);
int y1 = y0;
if (first1.size() > 0) {
g2.setColor(gridColor);
g2.drawLine(padding + labelPadding + 1 + pointWidth, y0, getWidth() - padding, y1);
g2.setColor(Color.BLACK);
String yLabel = ((int) ((getMinScore() + (getMaxScore() - getMinScore()) * ((i * 1.0) / numberYDivisions)) * 100)) / 100.0 + "";
FontMetrics metrics = g2.getFontMetrics();
int labelWidth = metrics.stringWidth(yLabel);
g2.drawString(yLabel, x0 - labelWidth - 5, y0 + (metrics.getHeight() / 2) - 3);
}
g2.drawLine(x0, y0, x1, y1);
}
g2.drawLine(padding + labelPadding, getHeight() - padding - labelPadding, padding + labelPadding, padding);
g2.drawLine(padding + labelPadding, getHeight() - padding - labelPadding, getWidth() - padding, getHeight() - padding - labelPadding);
Graphics g3 = g2;
Stroke oldStroke = g2.getStroke();
g2.setColor(lineColor);
g2.setStroke(GRAPH_STROKE);
System.out.println(graphPoints.size());
for (int i = 0; i < graphPoints.size() - 1; i++) {
int x1 = graphPoints.get(i).x;
int y1 = graphPoints.get(i).y;
int x2 = graphPoints.get(i + 1).x;
int y2 = graphPoints.get(i + 1).y;
g2.drawLine(x1, y1, x2, y2);
}
g3.setColor(Color.PINK);
for (int i = 0; i < graphPoints2.size() - 1; i++) {
int x1 = graphPoints2.get(i).x;
int y1 = graphPoints2.get(i).y;
int x2 = graphPoints2.get(i + 1).x;
int y2 = graphPoints2.get(i + 1).y;
g3.drawLine(x1, y1, x2, y2);
}
g2.setStroke(oldStroke);
g2.setColor(pointColor);
for (int i = 0; i < graphPoints.size(); i++) {
int x = graphPoints.get(i).x - pointWidth / 2;
int y = graphPoints.get(i).y - pointWidth / 2;
int ovalW = pointWidth;
int ovalH = pointWidth;
g2.fillOval(x, y, ovalW, ovalH);
}
for (int i = 0; i < graphPoints2.size(); i++) {
int x = graphPoints2.get(i).x - pointWidth / 2;
int y = graphPoints2.get(i).y - pointWidth / 2;
int ovalW = pointWidth;
int ovalH = pointWidth;
g3.fillOval(x, y, ovalW, ovalH);
}
}
#Override
public Dimension getPreferredSize() {
return new Dimension(width, heigth);
}
private double getMinScore() {
double minScore =0;
if (Collections.min(first1)<=Collections.max(second1)){
minScore= Collections.min(first1)-10;
}
else{
minScore = Collections.min(second1)-10;
}
return minScore;
}
private double getMaxScore() {
double maxScore =0;
if (Collections.max(first1)>=Collections.max(second1)){
maxScore= Collections.max(first1)+10;
}
else{
maxScore = Collections.max(second1)+10;
}
return maxScore;
}
Sorry for the wall of code, I couldn't decide what was relevant and what isn't.

The main clue here is the repeated messages. Either paintComponent is getting called a bunch of times, or you have a bunch of components getting painted. From this block in the action listener, it looks like the later:
if(testx != null)
testx.removeAll();
testx = new GraphPanel(first,second);
addItem(Mainpanel, testx, 0,20, 20,20, GridBagConstraints.SOUTH);
It removes all of the children from testx, then makes a new one and adds it to Mainpanel. What it doesn't do is remove the old testx from Mainpanel, so they're building up.

LIBGDX: How do I draw a filled polygon with the shaperenderer?

I have defined a shape using an array of vertices:
float[] points = new float[]{50,60,50,70,60,70, 60,60,50,60};
And I am drawing this here:
shapeRenderer.polygon(floatNew);
This just gives an outline of the shape.
How do I fill it with colour?
Thanks

Currently, ShapeRenderer supports polygon drawing (by line) but not filling.
This code is clipping the polygon on triangles, and then drawing each triangle separately.
Edit ShapeRenderer.java like this:
EarClippingTriangulator ear = new EarClippingTriangulator();
public void polygon(float[] vertices, int offset, int count)
{
if (shapeType != ShapeType.Filled && shapeType != ShapeType.Line)
throw new GdxRuntimeException("Must call begin(ShapeType.Filled) or begin(ShapeType.Line)");
if (count < 6)
throw new IllegalArgumentException("Polygons must contain at least 3 points.");
if (count % 2 != 0)
throw new IllegalArgumentException("Polygons must have an even number of vertices.");
check(shapeType, null, count);
final float firstX = vertices[0];
final float firstY = vertices[1];
if (shapeType == ShapeType.Line)
{
for (int i = offset, n = offset + count; i < n; i += 2)
{
final float x1 = vertices[i];
final float y1 = vertices[i + 1];
final float x2;
final float y2;
if (i + 2 >= count)
{
x2 = firstX;
y2 = firstY;
} else
{
x2 = vertices[i + 2];
y2 = vertices[i + 3];
}
renderer.color(color);
renderer.vertex(x1, y1, 0);
renderer.color(color);
renderer.vertex(x2, y2, 0);
}
} else
{
ShortArray arrRes = ear.computeTriangles(vertices);
for (int i = 0; i < arrRes.size - 2; i = i + 3)
{
float x1 = vertices[arrRes.get(i) * 2];
float y1 = vertices[(arrRes.get(i) * 2) + 1];
float x2 = vertices[(arrRes.get(i + 1)) * 2];
float y2 = vertices[(arrRes.get(i + 1) * 2) + 1];
float x3 = vertices[arrRes.get(i + 2) * 2];
float y3 = vertices[(arrRes.get(i + 2) * 2) + 1];
this.triangle(x1, y1, x2, y2, x3, y3);
}
}
}

You cant draw a filled Polygon with the shaperender yet. take a look at this from the bugtracker
You can also read that in the API.
public void polygon(float[] vertices)
Draws a polygon in the x/y plane. The vertices must contain at least 3
points (6 floats x,y). The ShapeRenderer.ShapeType passed to begin has
to be ShapeRenderer.ShapeType.Line.
API ShapeRender
Sure if its with ShapeType.Line you just get the outlines.
You need to draw it yourself with Triangles in that case. It should be possible to fill at least Triangles.
Maybe take a look at this from Stackoverflow: drawing-filled-polygon-with-libgdx

Edit your ShapeRenderer.java class replacing polygon() method with the following code:
public void polygon(float[] vertices, int offset, int count) {
if (currType != ShapeType.Filled && currType != ShapeType.Line)
throw new GdxRuntimeException(
"Must call begin(ShapeType.Filled) or begin(ShapeType.Line)");
if (count < 6)
throw new IllegalArgumentException(
"Polygons must contain at least 3 points.");
if (count % 2 != 0)
throw new IllegalArgumentException(
"Polygons must have an even number of vertices.");
checkDirty();
checkFlush(count);
final float firstX = vertices[0];
final float firstY = vertices[1];
if (currType == ShapeType.Line) {
for (int i = offset, n = offset + count; i < n; i += 2) {
final float x1 = vertices[i];
final float y1 = vertices[i + 1];
final float x2;
final float y2;
if (i + 2 >= count) {
x2 = firstX;
y2 = firstY;
} else {
x2 = vertices[i + 2];
y2 = vertices[i + 3];
}
renderer.color(color);
renderer.vertex(x1, y1, 0);
renderer.color(color);
renderer.vertex(x2, y2, 0);
}
} else {
for (int i = offset, n = offset + count; i < n; i += 4) {
final float x1 = vertices[i];
final float y1 = vertices[i + 1];
if (i + 2 >= count) {
break;
}
final float x2 = vertices[i + 2];
final float y2 = vertices[i + 3];
final float x3;
final float y3;
if (i + 4 >= count) {
x3 = firstX;
y3 = firstY;
} else {
x3 = vertices[i + 4];
y3 = vertices[i + 5];
}
renderer.color(color);
renderer.vertex(x1, y1, 0);
renderer.color(color);
renderer.vertex(x2, y2, 0);
renderer.color(color);
renderer.vertex(x3, y3, 0);
}
}
}
Usage:
gdx_shape_renderer.begin(ShapeType.Filled);
gdx_shape_renderer.setColor(fill_r, fill_g, fill_b, fill_a);
gdx_shape_renderer.polygon(vertices);
gdx_shape_renderer.end();
gdx_shape_renderer.begin(ShapeType.Line);
gdx_shape_renderer.setColor(border_r, border_g, border_b, border_a);
gdx_shape_renderer.polygon(vertices);
gdx_shape_renderer.end();

Rotate Bitmap pixels

I'm trying to rotate a Bitmap where the pixels are stored in an Array int pixels[]. I got the following method:
public void rotate(double angle) {
double radians = Math.toRadians(angle);
double cos, sin;
cos = Math.cos(radians);
sin = Math.sin(radians);
int[] pixels2 = pixels;
for (int x = 0; x < width; x++)
for (int y = 0; y < height; y++) {
int centerx = this.width / 2, centery = this.height / 2;
int m = x - centerx;
int n = y - centery;
int j = (int) (m * cos + n * sin);
int k = (int) (n * cos - m * sin);
j += centerx;
k += centery;
if (!((j < 0) || (j > this.width - 1) || (k < 0) || (k > this.height - 1)))
try {
pixels2[(x * this.width + y)] = pixels[(k * this.width + j)];
} catch (Exception e) {
e.printStackTrace();
}
}
pixels = pixels2;
}
But it just gives me crazy results. Does anyone know where the error is?

The line
int[] pixels2 = pixels;
is supposed to copy the array, but you are just copying the reference to it. Use pixels.clone(). In fact, you just need a new, empty array, so new int[pixels.lenght] is enough. In the end you need System.arraycopy to copy the new content into the old array.
There are other problems in your code -- you are mixing up rows and columns. Some expressions are written as though the image is stored row by row, others as if column by column. If row-by-row (my assumption), then this doesn't make sense: x*width + y. It should read y*width + x -- you are skipping y rows down and then moving x columns to the right. All in all, I have this code that works OK:
import static java.lang.System.arraycopy;
public class Test
{
private final int width = 5, height = 5;
private int[] pixels = {0,0,1,0,0,
0,0,1,0,0,
0,0,1,0,0,
0,0,1,0,0,
0,0,1,0,0};
public Test rotate(double angle) {
final double radians = Math.toRadians(angle),
cos = Math.cos(radians), sin = Math.sin(radians);
final int[] pixels2 = new int[pixels.length];
for (int x = 0; x < width; x++)
for (int y = 0; y < height; y++) {
final int
centerx = this.width / 2, centery = this.height / 2,
m = x - centerx,
n = y - centery,
j = ((int) (m * cos + n * sin)) + centerx,
k = ((int) (n * cos - m * sin)) + centery;
if (j >= 0 && j < width && k >= 0 && k < this.height)
pixels2[(y * width + x)] = pixels[(k * width + j)];
}
arraycopy(pixels2, 0, pixels, 0, pixels.length);
return this;
}
public Test print() {
for (int y = 0; y < height; y++) {
for (int x = 0; x < width; x++)
System.out.print(pixels[width*y + x]);
System.out.println();
}
System.out.println();
return this;
}
public static void main(String[] args) {
new Test().print().rotate(-45).print();
}
}

public void render(float nx, float ny, float nz, float size, float rotate) {
int wid = (int) ((width - nz) * size);
int hgt = (int) ((height - nz) * size);
if (wid < 0 || hgt < 0) {
wid = 0;
hgt = 0;
}
for (int x = 0; x < wid; x++) {
for (int y = 0; y < hgt; y++) {
double simple = Math.PI;
int xp = (int) (nx +
Math.cos(rotate) * ((x / simple) - (wid / simple) / 2) + Math
.cos(rotate + Math.PI / 2)
* ((y / simple) - (hgt / simple) / 2));
int yp = (int) (ny + Math.sin(rotate)
* ((x / simple) - (wid / simple) / 2) + Math.sin(rotate
+ Math.PI / 2)
* ((y / simple) - (hgt / simple) / 2));
if (xp + width < 0 || yp + height < 0 || xp >= Main.width
|| yp >= Main.height) {
break;
}
if (xp < 0
|| yp < 0
|| pixels[(width / wid) * x + ((height / hgt) * y)
* width] == 0xFFFF00DC) {
continue;
}
Main.pixels[xp + yp * Main.width] = pixels[(width / wid) * x
+ ((height / hgt) * y) * width];
}
}
}
This is only a new to rotating for me, but the process of this is that of a normal rotation. It still needs much fixing -- it's inefficient and slow. But in a small program, this code works. I'm posting this so you can take it, and make it better. :)