I have an object called Boid which has a position and a velocity vector (the direction of movement). When updating the position, I want to apply a factor which the user can control. The following script does not work, however:
let speedFactor = 0.1; //ranges from 0 to 2 class Boid { constructor(x, y) { this.position = createVector(x, y); this.velocity = p5.Vector.random2D(); } update() { this.position.add(this.velocity * speedFactor); // doesn't work } } I also tried to use things like speedFactor = createVector(0.1, 0.1) or = [0.1, 0.1], but it doesn't work.
If I use this.velocity.mult(speedFactor), this will affect the velocity vector, which I don't want (e.g. because if speedFactor == 0, this.velocity will get messed up). I have tried to create a copy of the velocity vector to overcome this by using Object.assign({}, this.velocity) or JSON.parse(JSON.stringify(this.velocity)), but somehow that doesn't work neither.
Most of the time I get the error p5.Vector.prototype.mult: x, y, or z arguments are either undefined or not a finite number.
What would be the best to do here?
1 Answer
Copy the vector, then multiply it with the normal mult method
let speedFactor = 0.1; //ranges from 0 to 2 class Boid { constructor(x, y) { this.position = createVector(x, y); this.velocity = p5.Vector.random2D(); } update() { this.position.add(this.velocity.copy().mult(speedFactor)); } } 
