From 18c08d6b2bc22897b98177e44effe308ab25e59f Mon Sep 17 00:00:00 2001
From: hugova <hugova@kth.se>
Date: Thu, 3 Apr 2025 00:41:21 +0200
Subject: [PATCH] Pushed performance improvement from line_down to line_up

---
 wip-hugo/routines/line/line_up.s | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/wip-hugo/routines/line/line_up.s b/wip-hugo/routines/line/line_up.s
index b79da7d..e8da686 100644
--- a/wip-hugo/routines/line/line_up.s
+++ b/wip-hugo/routines/line/line_up.s
@@ -43,7 +43,11 @@ end_selfmod:
         jsr pixel_draw
         Sub_16 >btp_mem_pos, <btp_mem_pos, #$01, #$00 ;; Y has always a offset of at least 1
         LDY #$01
-        LDX X_pos
+        ;; X = X_end - X_pos
+        LDA X_end
+        SEC
+        SBC X_pos
+        TAX
 for_x:
         LDA byte_to_paint
         ORA (>btp_mem_pos), Y
@@ -56,8 +60,8 @@ move_8px_left:
         LDA #%10000000
         STA byte_to_paint
 increment_pixel_x_end:
-        INX
-        CPX X_end
+        DEX
+        ;CPX X_end
         BEQ end
         Lag_16 >D, <D, #$00, #$02, case_2
 case_1: