let isInside = require('point-inside-triangle')(triangle, point);

let isInside = require('point-inside-triangle')(    
    [
        [0, 0],// A
        [1, 0],// B
        [0, 1] // C
    ],
    [0.25, 0.25] //point
);
 
// isInside = true

//partial application
let inTriangle = require('point-inside-triangle')(
    [
        [0, 0],// A
        [1, 0],// B
        [0, 1] // C
    ]
);
 
let isInsideA = inTriangle([0.25, 0.25]);
// isInsideA = true
 
let isInsideB = inTriangle([0.75, 0.75]);
// isInsideB = false