"GUITAR.jpg"image is in data folder for this sketch. Can anyone explain NullPointerException error?

wowww

int y=300;
int vertex = 800;
int j=600;
PImage GUITAR;


void setup() {
  size(2200, 1600);
  background(80, 185, 255, 3);
  drawNeighborhood();
  GUITAR = loadImage("data/GUITAR.jpg");
  imageMode(CENTER);
}

void draw() {
  /*drawHouse(400,600);
   drawBlock(600);*/
}

void drawHouse(float x, int y) {
  strokeWeight(1);
  smooth();

  beginShape();
  fill(random(150, 250));
  vertex (x, y-100);
  vertex (x, y+50);//400,450
  vertex (x-300, y+50);
  vertex (x-300, y-100);
  vertex (x-150, y-250);
  vertex (x-90, y-180);
  vertex (x-90, y-220);
  vertex(x-40, y-220);
  vertex(x-40, y-145);//360,355
  vertex(x, y-100);//400,300
  endShape();
  strokeWeight(4);
  line(x-88, y-200, x-42, y-200);
  image(GUITAR, x, y);
}

void drawBlock(int y) {
  int xSpace=250;
  fill(255);



  if (y==300) {
    xSpace=xSpace;
  } else if (y==500) {
    xSpace+=xSpace;
  } else if (y==900) {
    xSpace+=xSpace/2;
  } else {
    xSpace=xSpace-150;
  }
  for (int x=400; x<=2200; x+=xSpace) {
    drawHouse(random(300, x), y);
  }
  fill(random(50, 100));
  strokeWeight(0);
  rect(0, y+50, width, 30);
}

void drawNeighborhood() {

  for (int y=300; y<=1600; y+=200) {

    drawBlock(y);
  }
}

wowww

Sorry obviously I'm a newbie! Don't know how to apply markdown to format above code properly!

quark

Highlight the code and press Ctrl +k

quark

Use loadImage("GUITAR.jpg") you dont need to specify the data folder Processing does that for you

wowww

Thanks for your response! I eliminated the data folder and get the same error message: Any other ideas?

int y=300;
int vertex = 800;
int j=600;
PImage GUITAR;


void setup() {
  size(2200, 1600);
  background(80, 185, 255, 3);
  drawNeighborhood();
  GUITAR = loadImage("GUITAR.jpg");
  imageMode(CENTER);
}

void draw() {
  /*drawHouse(400,600);
   drawBlock(600);*/
}

void drawHouse(float x, int y) {
  strokeWeight(1);
  smooth();

  beginShape();
  fill(random(150, 250));
  vertex (x, y-100);
  vertex (x, y+50);//400,450
  vertex (x-300, y+50);
  vertex (x-300, y-100);
  vertex (x-150, y-250);
  vertex (x-90, y-180);
  vertex (x-90, y-220);
  vertex(x-40, y-220);
  vertex(x-40, y-145);//360,355
  vertex(x, y-100);//400,300
  endShape();
  strokeWeight(4);
  line(x-88, y-200, x-42, y-200);
  image(GUITAR, x, y);
}

void drawBlock(int y) {
  int xSpace=250;
  fill(255);



  if (y==300) {
    xSpace=xSpace;
  } else if (y==500) {
    xSpace+=xSpace;
  } else if (y==900) {
    xSpace+=xSpace/2;
  } else {
    xSpace=xSpace-150;
  }
  for (int x=400; x<=2200; x+=xSpace) {
    drawHouse(random(300, x), y);
  }
  fill(random(50, 100));
  strokeWeight(0);
  rect(0, y+50, width, 30);
}

void drawNeighborhood() {

  for (int y=300; y<=1600; y+=200) {

    drawBlock(y);
  }
}

wowww

Copied and pasted for Markdown:

int y=300;
int vertex = 800;
int j=600;
PImage GUITAR;


void setup() {
  size(2200, 1600);
  background(80, 185, 255, 3);
  drawNeighborhood();
  GUITAR = loadImage("GUITAR.jpg");
  imageMode(CENTER);
}

void draw() {
  /*drawHouse(400,600);
   drawBlock(600);*/
}

void drawHouse(float x, int y) {
  strokeWeight(1);
  smooth();

  beginShape();
  fill(random(150, 250));
  vertex (x, y-100);
  vertex (x, y+50);//400,450
  vertex (x-300, y+50);
  vertex (x-300, y-100);
  vertex (x-150, y-250);
  vertex (x-90, y-180);
  vertex (x-90, y-220);
  vertex(x-40, y-220);
  vertex(x-40, y-145);//360,355
  vertex(x, y-100);//400,300
  endShape();
  strokeWeight(4);
  line(x-88, y-200, x-42, y-200);
  image(GUITAR, x, y);
}

void drawBlock(int y) {
  int xSpace=250;
  fill(255);



  if (y==300) {
    xSpace=xSpace;
  } else if (y==500) {
    xSpace+=xSpace;
  } else if (y==900) {
    xSpace+=xSpace/2;
  } else {
    xSpace=xSpace-150;
  }
  for (int x=400; x<=2200; x+=xSpace) {
    drawHouse(random(300, x), y);
  }
  fill(random(50, 100));
  strokeWeight(0);
  rect(0, y+50, width, 30);
}

void drawNeighborhood() {

  for (int y=300; y<=1600; y+=200) {

    drawBlock(y);
  }
}

koogs

^ mod edit.

koogs

ok, think about it.

line 10 drawNeighborhood

in drawHeighborhood() line 69 drawBlock

in drawBlock() line 58 drawHouse

in drawHouse() line 38 use the guitar image

but you only load the image in line 11, which is after line 10.

wowww

Thanks for your response! Sorry for my delay...

I moved the image to load in line... 9 (?) ...If you could also PLEASE explain to me how to prepare the code for Markdown, I'd be MUCH appreciative!

Anyway when I load the image earlier, I still get a "NullPointerException" error.

Thanks again for your help. I must be making silly mistakes. I'm a beginner!

int y=300;
int vertex = 800;
int j=600;
PImage GUITAR;


void setup() {
  size(2200, 1600);
  background(80, 185, 255, 3);
  GUITAR = loadImage("GUITAR.jpg");
  drawNeighborhood();

  imageMode(CENTER);
}

void draw() {
  /*drawHouse(400,600);
   drawBlock(600);*/
}

void drawHouse(float x, int y) {

  strokeWeight(1);
  smooth();

  beginShape();
  fill(random(150, 250));
  vertex (x, y-100);
  vertex (x, y+50);//400,450
  vertex (x-300, y+50);
  vertex (x-300, y-100);
  vertex (x-150, y-250);
  vertex (x-90, y-180);
  vertex (x-90, y-220);
  vertex(x-40, y-220);
  vertex(x-40, y-145);//360,355
  vertex(x, y-100);//400,300
  endShape();
  strokeWeight(4);
  line(x-88, y-200, x-42, y-200);
  image(GUITAR, x, y);
}

void drawBlock(int y) {
  int xSpace=250;
  fill(255);



  if (y==300) {
    xSpace=xSpace;
  } else if (y==500) {
    xSpace+=xSpace;
  } else if (y==900) {
    xSpace+=xSpace/2;
  } else {
    xSpace=xSpace-150;
  }
  for (int x=400; x<=2200; x+=xSpace) {
    drawHouse(random(300, x), y);
  }
  fill(random(50, 100));
  strokeWeight(0);
  rect(0, y+50, width, 30);
}

void drawNeighborhood() {

  for (int y=300; y<=1600; y+=200) {

    drawBlock(y);
  }
}

PhiLho

".If you could also PLEASE explain to me how to prepare the code for Markdown, I'd be MUCH appreciative!"
Well, quark just told you that some messages ago.

Also see To newcomers in this forum: read attentively these instructions

And you can edit your messages.

quark

if you have an NPE there will be an error message in the bottom pane of the PDE please copy and paste it in this forum.

Chrisir

you can edit your last post....

How to post code

when you post your code:

• in the editor hit ctrl-t to auto format

• copy it

• paste it in the browser

• leave 2 empty lines before it, 1 line after it

• mark the code (without the 3 empty lines)

• press C in the small command bar.

Chrisir

GUITAR = loadImage("GUITAR.jpg");

the file name on the hard drive must be exactly like here, even small / capital letters....

• Guitar.jpg won't work

• GUITAR.JPG won't work

wowww

attempting

int y=300;
int vertex = 800;
int j=600;
PImage GUITAR;

void setup() {
    size(2200, 1600);
    background(80, 185, 255, 3);
    GUITAR = loadImage("GUITAR.jpg");
    drawNeighborhood();
    imageMode(CENTER);
}

void draw() {
    /*drawHouse(400,600);
    drawBlock(600);*/
}

void drawHouse(float x, int y) {

    strokeWeight(1);
    smooth();

    beginShape();
    fill(random(150, 250));
    vertex (x, y-100);
    vertex (x, y+50);//400,450
    vertex (x-300, y+50);
    vertex (x-300, y-100);
    vertex (x-150, y-250);
    vertex (x-90, y-180);
    vertex (x-90, y-220);
    vertex(x-40, y-220);
    vertex(x-40, y-145);//360,355
    vertex(x, y-100);//400,300
    endShape();
    strokeWeight(4);
    line(x-88, y-200, x-42, y-200);
    image(GUITAR, x, y);
}

Chrisir

How to post code

when you post your code:

• in the editor hit ctrl-t to auto format

• copy it

• paste it in the browser

• leave 2 empty lines before it, 1 line after it

• mark the code (without the 3 empty lines)

• press C in the small command bar.

Chrisir

just try

PImage GUITAR;

size(2200, 1600);

background(80, 185, 255, 3);
GUITAR = loadImage("GUITAR.jpg");
image(GUITAR, 0, 0);

Does it work??

;-)

wowww

Hello Quark: There is no text below the error NullPointerException.

Chrisir

can you post the entire console window?

PhiLho

When showing the error, the PDE should highlight a line. Tell us which one it is (I guess it is 39).

Do you have a file named GUITAR.jpg (exact case) in the data folder of your sketch?

As said, paste here the content of the console.

Chrisir

Is there a data folder in sketch folder?

Hit ctrl-k in the ide

wowww

Here is a screen shot of the entire editor and console (only excluding last closing curly bracket): Hope this works for anyone trying to check it out. There is a data folder in the sketch folder and GUITAR.jpg is in the data folder.

two things: •Thanks Chrisir for the simple image exercise which DOES work for me! •Also, as I mentioned way back, I'm trying to learn how to use functions and incorporate images, which is the point of this sketch to begin with. So the image isn't sized properly, etc. •Please pretend emoticon at bottom isn't there. Couldn't put it where I wanted it!

=D>

Chrisir

In setup load image before drawing neighbourhood

Chrisir

Also try x,y both float

Chrisir

Don't use vertex etc. as a name for a var

wowww

This is cool. Don't think I need to know why it works. I'll just remember to load image before function.

BUT what I wanted was to put the image in each house...?

ALSO thanks so much for your help with Markdown, but I don't know how to "mark the code" (your second to last line).

Thanks Again.

Chrisir

You really need to know why this works.... That's learning

You can't use the var GUITAR when there is no image in it - so you need to load first

Koogs told you that btw - why didn't it work back then??

wowww

ok, getter closer... but imageMode is set at (CENTER). What is the image centered on? Or how could I, for example, have the image be entirely inside the house and line up with the right side of the house?

wowww

About Koogs, you're right, good question. I did try then to move the image up before drawNeighborhood. I didn't save it so I don't know what else was going on with it at the time. And thank you, I do actually know its important to know WHY anything works and in this case you've really helped me understand this in the context of a specific problem.

wowww

code is there on Aug. 30. Problem was I moved loadImage up without imageMode. It looks like I'm being sloppy but its more that I don't understand basic concepts yet. (Like the centerMode image within shape defined by vertices... probably a math problem but I'm not sure how processing is choosing to center it where its centered right now.)

Chrisir

In setup imageMode too must be before drawing the neighbourhood to make it work.

Without centered when drawing an image x,y is the upper left corner

With centered x.y is the center of the image (so that half of its width is left from the x-value, the other half right of it)

Chrisir

imageMode CENTER refers to the images, such as

image(GUITAR, 0, 0);

just test it a in a separate small sketch.

imageMode CENTER does not refer to shapes though. That might be your current issue.

So your house is not centered around x,y

The way you draw it, it is mostly left from x,y since you say

vertex (x-300, y+50);

etc. which makes points far left from x.

To have the guitar centered in the house you can say

image(GUITAR, x-150, y-60);

;-)

Chrisir

this draws one house only

please note the red dot, that's your x,y for that house - the house is all left from it.

It's very good for testing to look at one house only.

int y=300;
int vertex = 800;
int j=600;
PImage GUITAR;

void setup() {
  size(2200, 1600);
  background(80, 185, 255, 3);
  GUITAR = loadImage("GUITAR.jpg");
  imageMode(CENTER);
  // drawNeighborhood();
  drawHouse(500, 300);

  // test 
  fill(255, 2, 2);
  noStroke();
  ellipse(500, 300, 7, 7);
}

void draw() {
  /*drawHouse(400,600);
   drawBlock(600);*/
}

void drawHouse(float x, int y) {

  strokeWeight(1);
  smooth();

  beginShape();
  fill(random(150, 250));
  vertex (x, y-100);
  vertex (x, y+50);//400,450
  vertex (x-300, y+50);
  vertex (x-300, y-100);
  vertex (x-150, y-250);
  vertex (x-90, y-180);
  vertex (x-90, y-220);
  vertex(x-40, y-220);
  vertex(x-40, y-145);//360,355
  vertex(x, y-100);//400,300
  endShape();
  strokeWeight(4);
  line(x-88, y-200, x-42, y-200);
  image(GUITAR, x-150, y-60);
}

void drawBlock(int y) {
  int xSpace=250;
  fill(255);



  if (y==300) {
    xSpace=xSpace;
  } 
  else if (y==500) {
    xSpace+=xSpace;
  } 
  else if (y==900) {
    xSpace+=xSpace/2;
  } 
  else {
    xSpace=xSpace-150;
  }
  for (int x=400; x<=2200; x+=xSpace) {
    drawHouse(random(300, x), y);
  }
  fill(random(50, 100));
  strokeWeight(0);
  rect(0, y+50, width, 30);
}

void drawNeighborhood() {

  for (int y=300; y<=330; y+=200) {  //   for (int y=300; y<=1600; y+=200) {


    drawBlock(y);
  }
}
//

Chrisir

full neighboorhood

int y=300;
int vertex = 800;
int j=600;
PImage GUITAR;

void setup() {
  size(2200, 1600);
  background(80, 185, 255, 3);
  GUITAR = loadImage("GUITAR.jpg");
  imageMode(CENTER);
  drawNeighborhood();
  // drawHouse(500, 300);

  // test 
  //  fill(255, 2, 2);
  //  noStroke();
  //  ellipse(500, 300, 7, 7);
}

void draw() {
  /*drawHouse(400,600);
   drawBlock(600);*/
}

void drawHouse(float x, int y) {

  strokeWeight(1);
  smooth();

  beginShape();
  fill(random(150, 250));
  vertex (x, y-100);
  vertex (x, y+50);//400,450
  vertex (x-300, y+50);
  vertex (x-300, y-100);
  vertex (x-150, y-250);
  vertex (x-90, y-180);
  vertex (x-90, y-220);
  vertex(x-40, y-220);
  vertex(x-40, y-145);//360,355
  vertex(x, y-100);//400,300
  endShape();
  strokeWeight(4);
  line(x-88, y-200, x-42, y-200);
  image(GUITAR, x-150, y-60);
}

void drawBlock(int y) {
  int xSpace=250;
  fill(255);

  if (y==300) {
    xSpace=xSpace;
  } 
  else if (y==500) {
    xSpace+=xSpace;
  } 
  else if (y==900) {
    xSpace+=xSpace/2;
  } 
  else {
    xSpace=xSpace-150;
  }
  for (int x=400; x<=2200; x+=xSpace) {
    drawHouse(random(300, x), y);
  }
  fill(random(50, 100));
  strokeWeight(0);
  rect(0, y+50, width, 30);
}

void drawNeighborhood() {
  for (int y=300; y<=1600; y+=200) {  //   for (int y=300; y<=1600; y+=200) {
    drawBlock(y);
  }
}
//

wowww

Thanks for this Chrisir! I'm excited to get this to work. But I'm not sure how you determined the x,y values for the single house tested. I guess any y value on that line would have worked for the purposes of the test?

    //test 
        fill(255, 2, 2);
        noStroke();
        ellipse(500, 300, 7, 7);

There are 2 more things I'd like to try with this. One is to have a series of images appear i different houses randomly, which I think means I'll have to review arrays. I'd also like to now make a city of neighborhoods which will involve the challenge of manipulating scale within the functions. So you'll be hearing from me again soon, I'm sure.

This post is also meant to test whether or not I finally have Markdown worked out...

Chrisir

everything you say is correct...

the x,y value in single house is of course just a test without meaning

for different images use array and random()

also for scaling houses use scale()

see reference for all

;-)

wowww

Thanks so much for being so helpful!

Chrisir

sure!