The stroke() function is used to draw the lines and border around the text and shapes. The color object can be set in terms of RGB or HSB depending on the color mode. The color object can also be set as string in terms of RGB, RGBA, Hex CSS color or named color string. Syntax:
stroke( v1, v2, v3, alpha )
or
stroke( value )
or
stroke( gray, alpha )
or
stroke( values )
or
stroke( color )
Parameters:
- v1: It is used to set the red or hue value relative to current color range.
- v2: It is used to set the green or saturation value relative to current color range.
- v3: It is used to set the blue or brightness value relative to current color range.
- alpha: It is used to set the transparency of the drawing.
- value: It is used to set the value of color string.
- gray: It is used to set the gray value.
- values: It is an array containing the red, green, blue and alpha value.
- color: It is used to set the stroke color.
Below examples illustrate the stroke() function in p5.js: Example 1:
javascript
function setup() { // Create Canvas of given size createCanvas(400, 200); } function draw() { // Set the background color background(220); // Set the stroke width strokeWeight(10); // Set the stroke stroke('green'); // Set the filled color fill('white'); // Draw the circle circle(90, 90, 34); // Set the text size textSize(20); // Set the text to print text("GeeksForGeeks", 140, 100); } |
Output: 
Example 2:
javascript
function setup() { // Create Canvas of given size createCanvas(400, 200); } function draw() { // Set the background color background(220); // Set the stroke color stroke('orange'); // Set the stroke width to 10 strokeWeight(30); // Orange // Draw a line line(100, 50, 300, 50); // Set the stroke color stroke('white'); // Set the stroke width to 8 strokeWeight(30); // White // Draw a line line(100, 100, 300, 100); // Set stroke color stroke('green'); // Set the stroke width to 6 strokeWeight(30); // Green // Draw a line line(100, 150, 300, 150); } |
Output: 
Reference: https://p5js.org/reference/#/p5/stroke
