Calculates the top left corner of a square from any two x and y points.

points-to-square-top-left.js

/**
 * Gets the top left corner of a square from two vertices. Uses nested
 * if statements, but its the best way to opimize performance. Point
 * parameters can be passed in any order.
 * @param {object} point1 Object formatted as { x, y } on a cartesian graph
 * @param {object} point1 Object formatted as { x, y } on a cartesian graph
 * @returns {object} { x, y } of the top left corner on a square
 */
function getSquareTopLeft (point1, point2) {
    // Declare coordinate collection variables
    var x, y;

    // Optimized top left corner check
    if (point1.x > point2.x) {
        // start is in bottom right
        if (point1.y > point2.y) {
            x = point2.x;
            y = point2.y;

        // Start is in the top right
        } else {
            x = point2.x;
            y = point1.y;
        }

    } else if (point1.x < point2.x) {
        // start is in the top left
        if (point1.y < point2.y) {
            x = point1.x;
            y = point1.y;

        // start is in the bottom left
        } else {
            x = point1.x;
            y = point2.y;
        }

    // No rectangle
    } else {
        x = point1.x;
        y = point1.y;
    }

    return {
        x: x,
        y: y
    };
}