src/declarations.lisp @ 404182110a26

(in-package :chip8)


(declaim
  (ftype (function (chip)) load-font)
  (ftype (function (chip fixnum fixnum)) wrap)
  (ftype (function (chip int8 int8 int4) null) draw-sprite)
  (ftype (function (chip (integer (16)))) keyup keydown)
  (ftype (function (single-float) single-float) square saw)
  (ftype (function (chip) null) run-sound)
  (ftype (function (chip) null) decrement-timers run-timers)
  (ftype (function (chip) null) run-cpu emulate-cycle)
  (ftype (function (chip int16) null) dispatch-instruction)
  (ftype (function (chip)) reset)
  ; (ftype (function ()))
  )

(defun draw-sprite (chip start-x start-y size)
  (declare (type chip chip)
           (type int8 start-x start-y)
           (type int4 size))
  (with-chip (chip)
    (setf flag 0)
    (iterate
      (declare (iterate:declare-variables))
      (repeat size)
      (for (the fixnum i) :from index)
      (for (the fixnum y) :from start-y)
      (for sprite = (aref memory i))
      (iterate
        (declare (iterate:declare-variables))
        (for (the fixnum x) :from start-x)
        (for (the fixnum col) :from 7 :downto 0)
        (multiple-value-bind (x y draw) (wrap chip x y)
          (when draw
            (for old-pixel = (plusp (vref chip x y)))
            (for new-pixel = (plusp (get-bit col sprite)))
            (when (and old-pixel new-pixel)
              (setf flag 1))
            (setf (vref chip x y)
                  (if (xor old-pixel new-pixel) 255 0))))))
    (setf video-dirty t))
  nil)

; (start-profiling)
; (stop-profiling)