Ball not coming back after colliding in p5.js

javascript html web p5.js

Solution 1:

Currently your code isn't going to make the ball "come back" because while it is limiting the x and y positions, it doesn't change the x and y velocities (so once the ball gets to the edge it is just going to stick there). You also have a few defects in to edge limiting logic.

  1. Your sliders are always positive so the ball can only move down and to the right.
  2. When you check the y position against the minimum you modify the x position instead of the y position.
  3. When you check the x position against the minimum value you are adding the speeds, but presumably when this happens speed would be negative (i.e. moving to the left), so you still want to subtract.

var x, y, speedx, speedy;

function setup() {
  // make the canvas cover the window
  createCanvas(windowWidth, windowHeight);
  x = width / 2;
  y = height / 2;

  // create slider ranges such that things don't always go down and to the right
  speedx = createSlider(-10, 10, 2);
  speedx.position(10, 10);
  speedx.style("width", "200px");

  speedy = createSlider(-10, 10, 2);
  speedy.position(10, 50);
  speedy.style("width", "200px");
}

function draw() {
  background("white");

  x = x + speedx.value();
  y = y + speedy.value();
  if (x > width - 10) {
    x = x - speedx.value();
  }
  if (x < 10) {
    // presumably the reason we're going off the screen is that speedx is negative.
    x = x - speedx.value();
  }
  if (y > height - 10) {
    y = y - speedy.value();
  }
  if (y < 10) {
    y = y - speedy.value();
  }
  let color1 = color("black");
  fill(color1);
  ellipse(x, y, 20);
}
html, body {margin:0}
<script src="https://cdnjs.cloudflare.com/ajax/libs/p5.js/1.4.0/p5.js"></script>

Related

Is the sequence of the even Bernoulli numbers bounded?
Finding the equations of the lines and tangent to the circle
Quadratic Formula in Complex Variables
Propositional Logic - Can you Derive $C \to A$ from $A$ alone, given the introduction rule?
Solve $x\equiv 1\pmod2$, $x\equiv 2\pmod3$, $x\equiv 3\pmod4$, $x\equiv 4\pmod5$, $x\equiv 5\pmod6$ and $x\equiv 0\pmod7$
$1+a$ and $1-a$ in a ring are invertible if $a$ is nilpotent [duplicate]
Simplifying an Arctan equation
Is there a closed form formula for the Bernoulli numbers?
MLE of $\delta$ for the distribution $f(x)=e^{\delta-x}$ for $x\geq\delta$.
Finding generating function for the recurrence $a_0 = 1$, $a_n = {n \choose 2} + 3a_{n - 1}$
Bernoulli numbers explicit form
Values of the limit $\lim\limits_{x\to+\infty}\left(\sqrt{(x+a)(x+b)}-x\right)$