((code
  (label main
    (load-immediate $0 &screen-namespace)
    (load-immediate $11 0)
    (syscall OPEN $0 $11)
    (syscall WRITE $0 $0 $0)

    (load-immediate $16 1) ; device info call
    (load-immediate $17 16) ; sizeof screen device info
    (malloc $18 $17)
    (syscall IOCTL $0 $16 $18)
    (load-immediate $1 12) ; offset for width
    (add-nat $19 $18 $1)
    (load-r $20 $19) ; load width
    (load-immediate $1 4) ; offset for width
    (add-nat $19 $18 $1)
    (load-r $21 $19) ; load base pointer
    (add-nat $21 $21 $1) ; need to add offset for fat pointer size

    (load-immediate $16 &mouse-namespace)
	  (load-immediate $3 12) ; malloc sizeof mouse data
	  (malloc $4 $3)

    (label draw-loop
      ; load mouse click data
	  	(syscall READ $16 $2 $3 $4)
      (load-immediate $5 4) ; offset for x
      (add-nat $6 $5 $2)
      (load-r $7 $6) ; load x
      (load-immediate $5 8) ; offset for y
      (add-nat $6 $5 $2)
      (load-r $8 $6) ; load y
      (load-immediate $5 12) ; offset for btn1
      (add-nat $6 $5 $2)
      (load-r8 $9 $6) ; load btn1 pressed
      (load-immediate $5 13) ; offset for btn2
      (add-nat $6 $5 $2)
      (load-r8 $10 $6) ; load btn2 pressed

      (jump-eq-nat &draw-loop $9 $11)

      ; Compute start address: y*width + x
      (mul-nat $15 $8 $20)        ; $15 = y * width
      (add-nat $15 $15 $7)        ; $15 += x
      (add-nat $15 $21 $15)       ; $15 = base + pixel_offset

      (load $3 &WHITE) ; color
      (store-8 $15 $3) ; draw color at screen [x,y]
      (syscall WRITE $0 $0 $0) ; redraw

      (jump-eq-nat &draw-loop $10 $11))
    (halt))
  (label println 
		(load-immediate $0 &terminal-namespace)
		(load-immediate $3 &new-line)
		(pop $1)
		(string-length $2 $1)
		(syscall WRITE $0 $1 $2)
		(string-length $4 $3)
		(syscall WRITE $0 $3 $4)
		(return)))
(data
  (label screen-namespace "/dev/screen/0")
  (label mouse-namespace "/dev/mouse/0")
  (label terminal-namespace "/dev/term/0")
	(label new-line "\n")
	(label WHITE 255)))