reduse a STA instruction in circle code

wip-hugo/routines/circle/circle.inc

@@ -5,16 +5,15 @@
         ;; and others from pixel.inc
 ;; private args
         t1    = $E0
-        t2    = $E1
         X_math = radius
-        Y_math = $E2
-        byte_to_paint_qaa = $E3
-        byte_to_paint_qcb = $E4
-        byte_to_paint_qca = $E5
-        byte_to_paint_qdb = $E6
+        Y_math = $E1
+        byte_to_paint_qaa = $E2
+        byte_to_paint_qcb = $E3
+        byte_to_paint_qca = $E4
+        byte_to_paint_qdb = $E5
 
         btp_mem_pos_qaa = btp_mem_pos
-        btp_mem_pos_qcb = $E7 ; 16bit value (uses E8)
+        btp_mem_pos_qcb = $E6 ; 16bit value (uses E7)
                               ; E9 - EA is used by pixel.inc
         btp_mem_pos_qdb = $EB ; 16bit value (uses EC)
         btp_mem_pos_qda = $ED ; 16bit value (uses EE)
@@ -24,9 +23,9 @@
         btp_mem_pos_qbb = $D6 ; 16bit value (uses D7)
 
         Y_qda = $EF
-        Y_qdb = $D8
-        Y_qbb = $D9
-        Y_qaa = $DA
+        Y_qdb = $E8
+        Y_qbb = $D8
+        Y_qaa = $D9
         ;;Reuse addresses, be carful here!
         temp__ = Y_qaa
         temp_ = Y_qda

wip-hugo/routines/circle/circle.s

@@ -229,7 +229,7 @@ qcb_x_end:
         ;; t2 = t1 - x
         SEC
         SBC X_math
-        STA t2
+        ;t2 do not need to be saved :)
         ;; if t2 < 0 then skip to endif
         ;; we can skipp CMP #$00 because SBC above do the same
         BPL if