Creating vectors as global variables

drawcult

When I use createVector() to assign a vector object to a global variable I get an object error. I've been working around the issue by creating a custom object that contains the vector objects I need and assigning the custom object to a global variable. I'm curious why it isn't possible to assign vector objects to global variables, any ideas?

Chrisir

PVector p1 = new PVector (23,232);

quark

You might look at this discussion

GoToLoop

At the P5.JS' "Necklace" sketch, "global" variable vel is assigned a p5.Vector from createVector():

const vel=Object.seal(createVector());

http://forum.processing.org/two/discussion/7294/why-doesnt-my-sketch-run-in-javascript-mode

So I don't get why you couldn't do the same! @-)

drawcult

Thanks GoToLoop! Didn't think to seal the vector object, that works!

GoToLoop

Oh, Object.seal() or Object.freeze() got nothing to do w/ it! :(|)
Those were my attempt experiments at making objects "immutable" in JS.
They can be removed w/o any side effects at all! :-j

const vel = createVector();

drawcult

I guess I should have included some code, the issue I was having was that

function() setup{
        pos = createVector(0,0);
        vel = createVector(0,0);
}

function() draw{
        pos.add(vel);
}

was throwing me an object error. Actually now that I check, that isn't happening anymore today...

GoToLoop

• It's true that pos & vel are being created as global variables inside your setup().
• However, it's frowned upon doing so via that fashion in JS.
• Variables should be created w/ var, const, or let keywords!

Either declare them at the top and then initialize them within setup():

var pos, vel;

function setup() {
  pos = createVector(), vel = createVector();
}

function draw() {
  pos.add(vel);
}

Or declare & initialize them at the top:

const pos = createVector(), vel = createVector();

function draw() {
  pos.add(vel);
}