Enhanced to support negative values for all 4 inputs

clickdrag.swift

#!/usr/bin/env xcrun swift
// ~/bin/clickdrag -x 10 -y 20 -dx 200 -dy 100 -negx true -negy false -negdx false -negdy false
// http://www.paulcalnan.com/archives/2014/10/quicktime-screen-recording-of-a-single-window.html
import Foundation

let kDelayUSec : useconds_t = 500_000

func DragMouse(from p0: CGPoint, to p1: CGPoint) {
    let mouseDown = CGEvent.init(mouseEventSource:nil,
                                 mouseType:.leftMouseDown,
                                 mouseCursorPosition:p0,
                                 mouseButton:.left)!
    let mouseDrag = CGEvent.init(mouseEventSource:nil,
                                 mouseType:.leftMouseDragged,
                                 mouseCursorPosition:p1,
                                 mouseButton:.left)!
    let mouseUp = CGEvent.init(mouseEventSource:nil,
                               mouseType:.leftMouseUp,
                               mouseCursorPosition:p1,
                               mouseButton:.left)!

    mouseDown.post(tap: .cghidEventTap)
    usleep(kDelayUSec)
    mouseDrag.post(tap: .cghidEventTap)
    usleep(kDelayUSec)
    mouseUp.post(tap: .cghidEventTap)
}

func main() {
    let args = UserDefaults.standard

    var x  = CGFloat(args.integer(forKey: "x"))
    var y  = CGFloat(args.integer(forKey: "y"))
    var dx = CGFloat(args.integer(forKey: "dx"))
    var dy = CGFloat(args.integer(forKey: "dy"))
    // Turns out you can't pass a negative integer to swift
    // this way.
    if (args.bool(forKey: "negx")) {
       x = -x;
    }
    if (args.bool(forKey: "negy")) {
       y = -y;
    }
    if (args.bool(forKey: "negdx")) {
       dx = -dx;
    }
    if (args.bool(forKey: "negdy")) {
       dy = -dy;
    }
    let p0 = CGPoint(x: x, y: y)
    let p1 = CGPoint(x: x + dx, y: y + dy)
    print(dx)

    DragMouse(from: p0, to: p1)
}

main()