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simple color sorter that used to work (Read 916 times)

bnagle

simple color sorter that used to work
Oct 30^th, 2008, 10:14pm

Hello, I'm working on a pretty simple little guy. It used to work in 0135. I've looked through the revisions and can't find why I'd be getting this error:

Exception in thread "Animation Thread" java.lang.NullPointerException

at java.lang.String.compareTo(String.java:998)

at java.lang.String.compareTo(String.java:90)

at java.util.Arrays.mergeSort(Arrays.java:1156)

at java.util.Arrays.mergeSort(Arrays.java:1168)

at java.util.Arrays.mergeSort(Arrays.java:1168)

at java.util.Arrays.mergeSort(Arrays.java:1167)

at java.util.Arrays.mergeSort(Arrays.java:1167)

at java.util.Arrays.mergeSort(Arrays.java:1167)

at java.util.Arrays.mergeSort(Arrays.java:1167)

at java.util.Arrays.mergeSort(Arrays.java:1167)

at java.util.Arrays.mergeSort(Arrays.java:1167)

at java.util.Arrays.mergeSort(Arrays.java:1167)

at java.util.Arrays.mergeSort(Arrays.java:1167)

at java.util.Arrays.mergeSort(Arrays.java:1167)

at java.util.Arrays.sort(Arrays.java:1118)

at processing.core.PApplet.sort(PApplet.java:4495)

at processing.core.PApplet.sort(PApplet.java:4488)

at colorPhotoHex.setup(colorPhotoHex.java:30)

at processing.core.PApplet.handleDraw(PApplet.java:1372)

at processing.core.PApplet.run(PApplet.java:1300)

at java.lang.Thread.run(Thread.java:613)

HERE'S THE CODE:

String[] Colors = new String[width*height];
PImage photo;
int count = 0;

size(4, 4);

photo= loadImage("photos/birch02.gif");
image(photo, 0, 0);
loadPixels();

for (int i = 0; i<pixels.length; i++){
String hVal = hex(pixels[i]);
Colors[i] = hVal;
}
Colors = sort(Colors);

for(int h=0; h<height; h++){
for(int w=0; w<width; w++){
color colorVal = unhex(Colors[count]);
//println(colorVal);
stroke(colorVal);
point(w,h);
count++;
}
}

save("colorSamples/" + photo + ".jpg");

Any help would be greatly appreciated

koogy

Re: simple color sorter that used to work
Reply #1 - Oct 31^st, 2008, 12:40am

i get an array out of bounds exception on the

Colors[i] = hVal;

line with i = 10,000. this is because width x height in the first line default to 100 x 100 before the size() call changes them (i made it 320x240 as that's how big my image was)

if i make the size 100x100 it's fine

if i make size 4x4 then Colors is still 100x100 but everything beyond Colors[4][4] is uninitialised, which is why the sort fails.

i would define WIDTH and HEIGHT myself and use them throughout

final int LENGTH = 4;
final int WIDTH = 4;
String[] Colors = new String[WIDTH * HEIGHT];

and

size(WIDTH, HEIGHT);

and also in the two for loops.

seems to work. i don't think the sort of colours does what you think it will though.

bnagle YaBB Newbies Offline Posts: 11	Re: simple color sorter that used to work Reply #2 - Nov 1^st, 2008, 11:25pm I'll give it a try, thanks for the help

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