Grx.set_viewport

function set_viewport(x: Number(gint), y: Number(gint)): Boolean {
    // Gjs wrapper for grx_set_viewport()
}

Sets the viewport on a virtual screen. The width and height of the viewport are determined by the physical screen size (Grx.get_screen_width and Grx.get_screen_height).

x: the left X coordinate of the viewport
y: the top Y coordinate of the viewport
Returns: true if setting the viewport was successful