What am i missing? (createImage)

Processing Coding Questions
1

Hey, i’m simply trying to create an image and set every pixel to white. What am i doing wrong here?

PImage img;
void setup() {
  img = createImage(500, 500, RGB);
  size(1920, 1080);
}
void draw() {

  img.loadPixels();
  for (int x=0; x<500; x++) {
    for (int y=0; y<500; y++) {
    img.set(x,y,color(255));
    }
  }

image(img,0,0);
}

It looks the same here: https://processing.org/reference/PImage_set_.html
Only difference is that i dont want to edit a image file but create a new image instead.

thank you in advance!

1 Like
2

Invoke PImage::get() w/o any arguments in order to get a clone of it: :smile_cat:

2 Likes
3

BtW, Arrays::fill():

Over the PImage::pixels[]:

Is much faster than any loop! :muscle:

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4

I don’t know why you are doing this, but if you want a more general interface to manipulating the pixels of an image, I might recommend PGraphics.

Now you can call beginDraw() and then use Processing methods to do things on your PGraphics pg. Want every pixel white? pg.background(255). Want to draw a line? pg.line(x,y,x2,y2). When you are done drawing, remember to call endDraw() and then display your image with image(pg, x, y).

PGraphics pg;

void setup() {
  size(1920, 1080);
  pg = createGraphics(500, 500);
}

void draw() {
  pg.beginDraw();
  pg.background(255);
  pg.endDraw();
  image(pg, 0, 0); 
}
1 Like
5

@Skranker When you modifiy your pixels, you need to call updatePixels(). Also, as mentioned before, using the pixels array associated with the PImage instead of calling set()

img.pixels[y*img.width+x]=color(255);

Also in your for loops, instead of using 500, I encourage you to use image.width and img.height in their respective loops. Good habit to start working on.

Kf

1 Like