ludic/examples/library/cursor_capture.ludic

# cursor_capture.ludic — cursor capture (#89): a windowed game hides / locks the
# OS mouse and draws its own reticle from the mouse position. Input.cursor_mode is
# a no-op headless (it only touches the platform cursor on a windowed build), so
# this compiles and links both ways; the capture behaviour is windowed-only.
#
# Run windowed:  bin/ludicc examples/library/cursor_capture.ludic -o /tmp/aim && /tmp/aim
program CursorCapture {
  property Tag { n: int = 0 }
  model P { Tag }

  @OnStart handler Boot {
    Input.cursor_mode(2)                 # 2 = locked: hide the OS cursor, feed relative motion
  }

  handler Draw phase Render {
    Screen.clear(0x101018)
    # a reticle drawn at the captured mouse position (a virtual cursor while locked)
    let mx = Input.mouse_x()
    let my = Input.mouse_y()
    Screen.fill_rectangle(mx - 3, my - 1, 7, 2, 0xffcc00)
    Screen.fill_rectangle(mx - 1, my - 3, 2, 7, 0xffcc00)
    Screen.show()
  }
}