Changing opacity of each shape seperately in an array p5.js - arrays

Question

I'm new to coding. I created a simple code and I need help with targeting each of the elements (each rectangle) in the array seperately. My goal is to change the opacity or transparency of each of the rectangles.
I can simply do fill(0, 255, 100, 50)and add an alpha value but this changes all of the rectangles..
I want to change the transparency - Alpha values: 50, 100, 150, 200, 250 respectively for each rectangle.
I tried to create an array for it and implement it to the rectangles but I can't seem to do it.
Here is the code, any help is appreciated :)
function setup() {
createCanvas(500, 110);
}
function draw() {
background(0, 100, 180);
stroke(2);
rectMode(CENTER);
for (var i = 0; i < 5; i++) {
fill(0,255, 100);
rect((i+1)*80, 50, 50, 50, 15);
}
}

Answer 1

You can dynamically define a color (including alpha attribute) using the color() function.
Here is a working example: https://editor.p5js.org/chen-ni/sketches/aWnKXEYh1
var alphaValues = [50, 100, 150, 200, 250];
function setup() {
createCanvas(500, 110);
}
function draw() {
background(0, 100, 180);
stroke(2);
rectMode(CENTER);
for (var i = 0; i < alphaValues.length; i++) {
var _alpha = alphaValues[i];
var _color = color(0, 255, 100, _alpha);
fill(_color);
rect((i + 1) * 80, 50, 50, 50, 15);
}
}