p5.js alpha() function
Last Updated :
10 Aug, 2023
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The alpha() function in p5.js is used to extract the alpha value from a color or pixel array.
Syntax:
c : This parameter stores the p5.Color object, color components, or CSS color.
Below program illustrates the alpha() function in p5.js:
Example-1:
javascript
Output:
Example-2:
javascript
Output:
Reference: https://p5js.org/reference/#/p5/alpha
alpha(c)Parameters: The function accepts single parameter as mentioned above and described below:
function setup() {
//create Canvas of size 300*80
createCanvas(300, 80);
}
function draw() {
background(220);
//initialize the parameter
let c = color(0, 126, 255, 102);
//extract the alpha value
let y = alpha(c);
textSize(16);
fill(color('red'));
text("Alpha Value is : " + y, 50, 30);
}
function setup() {
//create Canvas of size 300*80
createCanvas(160, 180);
}
function draw() {
background(220);
//initialize the parameter
let c = color(0, 126, 255, 34);
// Sets 'value' to 34
let value = alpha(c);
fill(value);
rect(50, 15, 35, 70);
text("Value of alpha is : " + value, 22, 110);
}
