the native window handle. If NativeWindowHandle.init, it will attempt to get the whole screen.
the width of the image you wish to capture. If 0, it will attempt to capture the full width of the target.
the height of the image you wish to capture. If 0, it will attempt to capture the full height of the target.
the x-offset of the image to capture, from the left.
the y-offset of the image to capture, from the top.
Added on March 14, 2021
Documented public on September 23, 2021 with full support for null params (dub 10.3)
Implementation used by SimpleWindow.takeScreenshot.