Save a few cycles in drunkwalk.

1 files changed, 10 insertions, 14 deletions

diff --git a/dla.s b/dla.s
index 3c61064..d379c42 100644
--- a/dla.s
+++ b/dla.s
@@ -568,27 +568,23 @@ dontplot:
 slow_x:
  ; (-1,0)
  ldx cursor_x
- dex
- ldy xoffsets,x
- lda xmasks,x
+ ldy xoffsets-1,x
+ lda xmasks-1,x
  and (pixptr),y
  bne stick
  ; (1,0)
- inx
- inx
- ldy xoffsets,x
- lda xmasks,x
+ ldy xoffsets+1,x
+ lda xmasks+1,x
  and (pixptr),y
  bne stick
 check_y:
  ; (0,-1)
- ldx cursor_y      ;3
- dex               ;2
- lda lineaddrs_l,x ;5
- sta pixptr        ;3
- lda lineaddrs_h,x ;5
- sta pixptr+1      ;3
-                   ;=21
+ ldx cursor_y        ;3
+ lda lineaddrs_l-1,x ;5
+ sta pixptr          ;3
+ lda lineaddrs_h-1,x ;5
+ sta pixptr+1        ;3
+                     ;=19
  ldx cursor_x
  ldy xoffsets,x
  lda xmasks,x