From da10566591539d02a22e11fd2f29c3a336f53d57 Mon Sep 17 00:00:00 2001
From: 4am <a2_4am@sent.com>
Date: Sat, 4 Dec 2021 21:23:11 -0500
Subject: [PATCH] shave some bytes

---
 src/fx/fx.shr.2pass.lr.a       |  2 ++
 src/fx/fx.shr.80boxes.common.a | 24 +++++++++++-------------
 src/fx/fx.shr.common.a         | 25 +++++++++++++++++--------
 src/fx/fx.shr.diagonal.a       |  2 ++
 src/fx/fx.shr.fizzle.a         |  3 ++-
 src/fx/fx.shr.lr.a             |  4 +++-
 src/fx/fx.shr.lr2.a            |  2 ++
 src/fx/fx.shr.ud.a             |  4 +++-
 8 files changed, 42 insertions(+), 24 deletions(-)

diff --git a/src/fx/fx.shr.2pass.lr.a b/src/fx/fx.shr.2pass.lr.a
index b1fe95e3c..54c8a94cf 100644
--- a/src/fx/fx.shr.2pass.lr.a
+++ b/src/fx/fx.shr.2pass.lr.a
@@ -17,7 +17,9 @@ shrhi = $38                          ; $C8 bytes
          bpl   -
 
          +BUILD_SHR_LOOKUP_TABLES shrlo, shrhi
+         ;X=0
          +COPY_SCB_AND_PALETTES
+         ;WRITEAUXMEM active
 
          jmp   loop1
 
diff --git a/src/fx/fx.shr.80boxes.common.a b/src/fx/fx.shr.80boxes.common.a
index 2d384618f..e596fc183 100644
--- a/src/fx/fx.shr.80boxes.common.a
+++ b/src/fx/fx.shr.80boxes.common.a
@@ -101,6 +101,10 @@ BoxesY    = $BEB0                    ; [$50 bytes][accessed via BoxesY-1][should
 --       ldy   #10
          lda   #$90
 -        sta   BoxesY-1, x
+         pha
+         lda   BoxInitialStages-1, x
+         sta   BoxStages-1, x
+         pla
          sec
          sbc   #$10
          dex
@@ -116,24 +120,18 @@ BoxesY    = $BEB0                    ; [$50 bytes][accessed via BoxesY-1][should
          sta   StageIndexes, x
          inx
          bne   -
-         ldx   #80                   ; can't do full $100 here because we'd clobber the stack
--        lda   BoxInitialStages-1, x
-         sta   BoxStages-1, x
-         dex
-         bne   -
          +BUILD_SHR_LOOKUP_TABLES shrlo, shrhi
+         ;X=0
          +COPY_SCB_AND_PALETTES
          ;WRITEAUXMEM active
          jmp   MainLoop
 
 start
 !pseudopc 0 {
-copy1
-         ldx   <topx+1
+copy1    ldx   <topx+1
          +SET_ROW_X
          ldy   <lefty+1
          jsr   across1
-copyexit
 ReBox    ldx   #$00                  ; [SMC] X = BoxLoop index 1..80
 NextBox  dex
          bne   BoxLoop
@@ -160,10 +158,10 @@ stage    ldx   #$00                  ; [SMC] X = stage index 1..7, reinitialized
          tya
          adc   <leftbyte-1, x
          sta   <lefty+1
-         lda   <siderows-1, x
-         sta   <rowcount
          dex
          beq   copy1
+         lda   <siderows-1, x
+         sta   <rowcount
          lda   <across_lo-1, x
          sta   <j+1
 topx     ldx   #$FD                  ; [SMC]
@@ -176,7 +174,7 @@ copy1row sec
 j        jsr   across7               ; [SMC low byte]
          inx
          bcc   copy1row
-         bvs   copyexit
+         bvs   ReBox
          sty   <righty+1
 copyside +SET_ROW_X
 lefty    ldy   #$FD                  ; [SMC]
@@ -209,8 +207,8 @@ src      sta   $FDFD, y              ; [SMC]
          rts
 
 toprow   !byte 12,10,8,6,4,2,0
-leftbyte !byte 6,5,4,3,2,1
-siderows !byte 0,1,5,9,13,17,21
+leftbyte !byte 6,5,4,3,2,1,0
+siderows !byte 1,5,9,13,17,21
 across_lo
          !byte <across2
          !byte <across3
diff --git a/src/fx/fx.shr.common.a b/src/fx/fx.shr.common.a
index a373300c7..b42d06750 100644
--- a/src/fx/fx.shr.common.a
+++ b/src/fx/fx.shr.common.a
@@ -2,6 +2,9 @@
 ;(c) 2021 by 4am
 
 !macro BUILD_SHR_LOOKUP_TABLES .lo, .hi {
+; in:    none
+; out:   X=0
+;        Z=1
          ldx   #$C8
          lda   #$60
          ldy   #$9C
@@ -23,6 +26,9 @@
 }
 
 !macro BUILD_SHR_REVERSE_LOOKUP_TABLES .lo, .hi {
+; in:    none
+; out:   X=0
+;        Z=1
          ldx   #$C8
          lda   #$00
          ldy   #$20
@@ -44,14 +50,17 @@
 }
 
 !macro COPY_SCB_AND_PALETTES {
+; in:    X=0 /!\
+; out:   X=0
+;        Z=1
+;        WRITEAUXMEM active
          sta   $C005
-         ldy   #0
--        lda   $9D00, y
-         sta   $9D00, y
-         lda   $9E00, y
-         sta   $9E00, y
-         lda   $9F00, y
-         sta   $9F00, y
-         iny
+-        lda   $9D00, x
+         sta   $9D00, x
+         lda   $9E00, x
+         sta   $9E00, x
+         lda   $9F00, x
+         sta   $9F00, x
+         inx
          bne   -
 }
diff --git a/src/fx/fx.shr.diagonal.a b/src/fx/fx.shr.diagonal.a
index ca5763352..01245ec48 100644
--- a/src/fx/fx.shr.diagonal.a
+++ b/src/fx/fx.shr.diagonal.a
@@ -17,7 +17,9 @@ shrhi = $201                         ; $C8 bytes
          bpl   -
 
          +BUILD_SHR_LOOKUP_TABLES shrlo, shrhi
+         ;X=0
          +COPY_SCB_AND_PALETTES
+         ;WRITEAUXMEM active
 
          jmp   colloop
 
diff --git a/src/fx/fx.shr.fizzle.a b/src/fx/fx.shr.fizzle.a
index a6e000703..a7db2102b 100644
--- a/src/fx/fx.shr.fizzle.a
+++ b/src/fx/fx.shr.fizzle.a
@@ -22,9 +22,10 @@ addrs=$80                            ; [128 bytes]
          dex
          bne   -
          ;X=0
+         ldy   #0
 
          +COPY_SCB_AND_PALETTES
-         ;Y=0
+         ;WRITEAUXMEM active
 
          jmp   loop
 
diff --git a/src/fx/fx.shr.lr.a b/src/fx/fx.shr.lr.a
index b9f9ab2bd..fdcaaf183 100644
--- a/src/fx/fx.shr.lr.a
+++ b/src/fx/fx.shr.lr.a
@@ -17,8 +17,10 @@ shrhi = $38                          ; $C8 bytes
          bpl   -
 
          +BUILD_SHR_LOOKUP_TABLES shrlo, shrhi
+         ;X=0
          +COPY_SCB_AND_PALETTES
-
+         ;WRITEAUXMEM active
+         ldy   #0
          jmp   loop
 
 start
diff --git a/src/fx/fx.shr.lr2.a b/src/fx/fx.shr.lr2.a
index a00de4cc6..854dfbefd 100644
--- a/src/fx/fx.shr.lr2.a
+++ b/src/fx/fx.shr.lr2.a
@@ -17,7 +17,9 @@ shrhi = $38                          ; $C8 bytes
          bpl   -
 
          +BUILD_SHR_LOOKUP_TABLES shrlo, shrhi
+         ;X=0
          +COPY_SCB_AND_PALETTES
+         ;WRITEAUXMEM active
 
          jmp   loop1
 
diff --git a/src/fx/fx.shr.ud.a b/src/fx/fx.shr.ud.a
index a49fe6d06..09c5ffa5b 100644
--- a/src/fx/fx.shr.ud.a
+++ b/src/fx/fx.shr.ud.a
@@ -18,9 +18,11 @@ reverseshrhi = $BE01                 ; $C8 bytes
          dex
          bpl   -
 
-         +BUILD_SHR_LOOKUP_TABLES shrlo, shrhi
          +BUILD_SHR_REVERSE_LOOKUP_TABLES reverseshrlo, reverseshrhi
+         +BUILD_SHR_LOOKUP_TABLES shrlo, shrhi
+         ;X=0
          +COPY_SCB_AND_PALETTES
+         ;WRITEAUXMEM active
 
          ldx   #$C8
          jmp   loop