Processing 1.0 - Processing Discourse - height and width change after calling draw()

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height and width change after calling draw() (Read 702 times)

sub-jean

height and width change after calling draw()
May 14^th, 2006, 2:27pm

First of all I have to say, I'm a total newbie to Processing. The problem iI desribe might result from this.

Basically, I want to load an image and filter it. For debugging I first of all just copied the pixels-array of the image to the pixels-array of the display. Here is the code:

PImage face;
int factor = 10;

void setup() {
int cWidth;
int cHeight;

face = loadImage("sw3.jpg");
cWidth = face.width;
cHeight = face.height;

size(cWidth, cHeight);
println("setup:height "+ height+" width "+width);
noLoop();
}

void draw() {
loadPixels();

println("draw:height "+ height+" width "+width);
println("draw:face.height "+ face.height+" face.width "+face.width);
for( int i=0; i<face.height*face.width; i++ ){
pixels[i] = face.pixels[i];
}
updatePixels();

}

I used the size of the image to initiate the window size. This should stay the same while this program is running. But it is not! The println commands in the setup() and draw() function give the following output:

setup:height 456 width 606
draw:height 456 width 606
draw:face.height 456 face.width 606
draw:height 461 width 608
draw:face.height 456 face.width 606

So, after the second call of draw() the height changes from 456 to 461. Why is that happening?

st33d

Re: height and width change after calling draw()
Reply #1 - May 14^th, 2006, 5:53pm

There is a topic on processinghacks about dynamic window size.

Size needs to be the first command you mention at the beginning of setup(). That's just unfortunately the way it works because size() is a special method. Furthermore, there should be no second call of draw(), you've specified noLoop(): the code in draw() will only be executed once.

Most of your operations on the image you are loading can be done off screen. I put an example below of how this can be done.
Code:


PImage pimage;

void setup() {
  size(400, 400);
  smooth();
  for(int i = 0; i < width; i += 6){
    ellipse(i, i, i, i);
  }
  loadPixels();
  pimage = new PImage(width, height);
  //the next method copies the screen into pimage
  pimage.copy(g, 0, 0, width, height, 0, 0, pimage.width, pimage.height);
}
 
void draw() {
  image(pimage, 0, 0);
}

void mousePressed(){
  for(int i = 0; i < pimage.pixels.length; i++){
    pimage.pixels[i] = color(255 - red(pimage.pixels[i]));
  }
  pimage.updatePixels();
}

sub-jean

Re: height and width change after calling draw()
Reply #2 - May 14^th, 2006, 6:18pm

Thank you for the reply!

But the problem is still there! No matter when I call size() it will change after the first call of draw().
See println-output:
Code:


setup:height 456 width 606
draw:height 456 width 606
draw:face.height 456 face.width 606
draw:height 461 width 608
draw:face.height 456 face.width 606

And yes, it is strange that draw() is called twice. It shouldn't do that since there is the noLoop() command.

Here is the slim code again that produced the output posted above
Code:


PImage face;

void setup() {
  size(606,456);
  
  face = loadImage("sw2.jpg");
  println("setup:height "+ height+" width "+width);

    noLoop();
}

void draw() {
  image( face, 0, 0);
  
  println("draw:height "+ height+" width "+width);
  println("draw:face.height "+ face.height+" face.width "+face.width);

}

st33d God Member Offline Posts: 666	Re: height and width change after calling draw() Reply #3 - May 14^th, 2006, 8:16pm I've just tried your code with an .jpg of my own and I can't reproduce your error, draw-size didn't change. I didn't get a double printout either. Have you tried other images to see if the error is the same? I used Processing 114 on a PC.

sub-jean YaBB Newbies Offline Posts: 4	Re: height and width change after calling draw() Reply #4 - May 14^th, 2006, 8:46pm I actually used 115 before and switched to 114. Each time the same error ocurred. I also tried another jpg. Same problem! I use a PC and Linux. Really strange! Maybe I should just restart my machine?

fry YaBB Moderator Offline Posts: 2623 mass, usa	Re: height and width change after calling draw() Reply #5 - May 15^th, 2006, 2:27am seems to be a linux bug, you're the second to report it... not sure why it's trying to keep resizing the frame like that: http://dev.processing.org/bugs/show_bug.cgi?id=341

sub-jean YaBB Newbies Offline Posts: 4	Re: height and width change after calling draw() Reply #6 - May 15^th, 2006, 8:24am That's a bit unfortunate! Is it worth to report it as a bug?

fjen God Member Offline Posts: 965	Re: height and width change after calling draw() Reply #7 - May 15^th, 2006, 10:27am i think the link in bens post is already a bug-report on that ... anyway, he is now aware of it.

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