Call an object within PGraphics?

Programming Questions

stttttt

Call an object within PGraphics?

in Programming Questions • 2 years ago

Hello,

I am new to Processing and programming, so the question may seem strange, but...

Can I call object within PGraphics?

Basically I am trying to do this (the objects are created lower, but I figured there's little need in posting all the object values etc). So here is the code (now it won't work - pg.myEyelid.look is not recognized).

void draw() {

noStroke();

background(255);

pg.beginDraw();

pg.background(trackBlack);

pg.scale(0.5, 0.5);

pg.myEyelid.look(); //How can I call these objects within PGraphics?

pg.myEyelid.blink();

pg.endDraw();

loadPixels();

for (int g = 0; g<cols; g++) {

for (int j =0; j<rows; j++) {

int a = g*pscale;

int b = j*pscale;

color c = pg.pixels[g+j*pg.width];

fill(c);

noStroke();

rect(a,b,pscale,pscale);

}

updatePixels();

println(bezierRef);

}

class Eyelid {

etc...

}

Replies(5)

PhiLho

Re: Call an object within PGraphics?

2 years ago

You don't call an object within PGraphics (unless you make a class extending it, but that's another story), you can methods on your object that accepts a PGraphics as parameter:
myEyelid.look(pg);
and in Eyelid:
void look(PGraphics pg) {
pg.line( ... ); // or other method calls.
}
Note: your .blink() might not work if it spawns several frames...

stttttt

Re: Call an object within PGraphics?

2 years ago

Thank you very much for the answer. I tried to figure the thing out, but it doesn't quite work yet.. Can you please point out, what have I done wrong? The sketch works fine until I put in the PGraphics into it.

Also you mentioned it won't work with several frames. I have a simple animation (just an "if" statement, which changes the position of lines, until they hit the certain number). Is there any way to do this kind of animation with PGraphics? Do I have to create something like "PGraphics pg2"? Thank you very much!!

int n = 20;

int m = 670;

Eyelid myEyelid;

boolean eyelidClose = true;

color trackBlack = 0;

color trackWhite = 255;

color trackGrey = 100;

PGraphics pg;

void setup() {

size(1024,768);

frameRate(24);

smooth();

noStroke();

myEyelid = new Eyelid(pg);

pg = createGraphics(width, height, JAVA2D);

}

void draw() {

noStroke();

background(255);

pg.beginDraw();

myEyelid.look(pg);

// myEyelid.blink(pg);

pg.endDraw();

}

class Eyelid {

int eyelidX1, eyelidY1, eyelidX2, eyelidY2, bezierX1, bezierY1, bezierX2, bezierY2, bezierY3, bezierY4;

Eyelid(PGraphics pg) {

eyelidX1=20;

eyelidY1=350;

eyelidX2=1004;

eyelidY2=350;

bezierX1=100;

bezierY1=20;

bezierX2=800;

bezierY2=20;

bezierY3=700;

bezierY4=640;

}

void look(PGraphics pg) {

pg.noStroke();

pg.fill(trackBlack);

pg.loadPixels();

pg.beginShape();

pg.vertex(eyelidX1, eyelidY1);

pg.bezierVertex(bezierX1, bezierY2, bezierX2, bezierY2, eyelidX2, eyelidY2);

pg.bezierVertex(bezierX2, bezierY3, bezierX1, bezierY3, eyelidX1, eyelidY1);

pg.endShape();

}

droidball..

Re: Call an object within PGraphics?

2 years ago

First off you need to create the PGraphics object before passing it to the Eyelid constructor

Reverse these lines

myEyelid = new Eyelid(pg);
pg = createGraphics(width, height, JAVA2D)

pg = createGraphics(width, height, JAVA2D);
myEyelid = new Eyelid(pg);

also in your Eyelid class

class Eyelid{
PGraphics pg;
Eyelid(PGraphics pgraphics){
pg = pgraphics;
}
}

Now the class Eyelid holds a PGraphics object called pg which you then can call from other class methods, as you do in look() for instance.

This means you don't need to pass a PGraphics object into the methods anymore since it's already in the class.

In other words, you can now just call

myEyelid.look(); // the myEyelid instance holds its own reference to the PGraphics object which you passed into the constructor

Hope this helps :)

stttttt

Re: Call an object within PGraphics?

2 years ago

Thank you very much, looks like this helped =))

PhiLho

Re: Call an object within PGraphics?

2 years ago

Yes, either you pass pg in the constructor or in the look() call, doing both isn't useful.
Beside, why are you drawing in a PGraphics? Are you doing some side treatment of it later? Because you can draw directly on the sketch's surface, otherwise.
You cannot do an animation in a PGraphics (in the sense of "canning the sequence of images there"). You do an animation by using draw(): it is called x times per second, you usually erase the background and draw on the sketch for each frame, creating the animated effect this way.

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