From 156abddbe78a1da426cbd539cdc7179a50cd6784 Mon Sep 17 00:00:00 2001
From: hugova <hugova@kth.se>
Date: Thu, 10 Jul 2025 16:40:14 +0200
Subject: [PATCH] reduse SEC instruction from circle-draw

---
 wip-hugo/routines/circle/circle.s | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/wip-hugo/routines/circle/circle.s b/wip-hugo/routines/circle/circle.s
index 50573ad..e8cf1f2 100644
--- a/wip-hugo/routines/circle/circle.s
+++ b/wip-hugo/routines/circle/circle.s
@@ -134,7 +134,9 @@ draw_right_px_in_circle:; similar as above
 
 
         LDX #$08 ; X=8 always expected inside the loop
-while_x_bigger_then_y:
+
+        SEC
+while_x_bigger_then_y: ; C=1 here because above and branching logic
 draw_pixels:
 draw_qaa:
         LDY Y_qaa
@@ -187,7 +189,8 @@ qaa_y:
 qaa_y_underflow:
         ;; Switch to chunk bellow
         ; So we subtract  #$0140
-        Sub_16 btp_mem_pos, btp_mem_pos + 1, #$40, #$01 ;-320
+        ;; Note that C =1, read from while_x_bigger_then_y label.
+        Sub_16 btp_mem_pos, btp_mem_pos + 1, #$40, #$01, ! ;-320
         Sub_16 btp_mem_pos_qba, btp_mem_pos_qba + 1, #$40, #$01,!
         STY Y_qaa ; Y_qaa =$07
 qaa_y_end: