From 7016042cff8791e37fb5afff2d2bc3461f75836b Mon Sep 17 00:00:00 2001
From: RochesterX <trevorisaacmaze@gmail.com>
Date: Sat, 21 Feb 2026 14:31:21 -0500
Subject: [PATCH] Stable scrolling and nametable logging

---
 plat.nes | Bin 40976 -> 40976 bytes
 plat.s   | 181 ++++++++++++++++++++++++++++++++++---------------------
 2 files changed, 113 insertions(+), 68 deletions(-)

diff --git a/plat.nes b/plat.nes
index 82e5f6bb6ad04a961400e53a760db58b787ea3a9..9c9c72f43616632cfbbd307ef4c4cefcb735271c 100644
GIT binary patch
delta 919
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zDwvVdRD(fGmBs8e8nJgV7vEzVoCT@@99(3ro3gIhFRkl%BEC;+exOZ&_`aY~Kw|(7
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zmfEDO01gMTC@eq7k*hK&T%zEttqUa@A4WV8f1xmrpeQ`68qdMi*=`Q=Qd&Sff!H~Q
zq`<=^d*Tp2*`zJM`2z`rpM*<>;F-!?!aO<=%Sg-alj0Dkvp7hy2oj@ID8@HJC}f4J
zJm%~Whh6z)-kyyw_n$ykvS&$-{n>GN%t|L#BuX2ec4?tW&GB$Wg%1lbT7Vx_`BR>p
zZn<K-@Z4DFAt@zR>g__w3qPYu{dH0E!TN@M-mi3bh1O1qdX!W}Q-FV>ZyfZkah^H7
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za>eZfk!&+%Y<Sn{ym5z(`g+I-$;h$uGhbCH%?v&*673(@KPbyiOnvqXn~<&)q%`}t
d<~d(NdisxM?Xho~Ha_?|wI_kZYK_aX@Hg@mUAq7P

delta 889
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z9rj3>P`9AJB=%aFK{fVigap(Zrd}|U%He;k^*1$;-xI~;KZ+Y~)hWaxWSK4bu9?zd
XjP*i7>LAd@OaJ11p}Mj`G79|#)oDoD

diff --git a/plat.s b/plat.s
index 026eb41..a639ff6 100644
--- a/plat.s
+++ b/plat.s
@@ -279,20 +279,37 @@ level:
 
 level2:
 .byte 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0
-.byte 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0
-.byte 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0
-.byte 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0
-.byte 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0
-.byte 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0
+.byte 0,1,0,0,1,0,0,0,0,1,0,0,2,7,7,3
+.byte 0,0,0,0,0,0,0,0,0,0,0,0,6,0,0,9
+.byte 0,1,0,0,1,7,7,7,7,1,7,7,6,0,0,9
+.byte 0,0,1,1,0,0,0,0,0,1,0,0,4,8,8,5
+.byte 0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0
 .byte 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0
 .byte 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0
 .byte 0,0,0,0,1,1,1,1,1,0,0,0,0,0,0,0
 .byte 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0
 .byte 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0
 .byte 0,0,0,0,0,0,0,0,0,0,0,10,10,10,10,10
+.byte 0,0,1,0,0,0,0,1,0,0,0,11,11,11,11,11
+.byte 0,1,2,3,4,5,6,7,8,9,0,11,11,11,11,11
 .byte 0,0,0,0,0,0,0,0,0,0,0,11,11,11,11,11
-.byte 0,1,7,7,7,7,7,7,7,1,0,11,11,11,11,11
-.byte 0,0,0,0,0,0,0,0,0,0,0,11,11,11,11,11
+
+;level2:
+;.byte 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0
+;.byte 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0
+;.byte 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0
+;.byte 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0
+;.byte 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0
+;.byte 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0
+;.byte 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0
+;.byte 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0
+;.byte 0,0,0,0,1,1,1,1,1,0,0,0,0,0,0,0
+;.byte 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0
+;.byte 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0
+;.byte 0,0,0,0,0,0,0,0,0,0,0,10,10,10,10,10
+;.byte 0,0,0,0,0,0,0,0,0,0,0,11,11,11,11,11
+;.byte 0,1,7,7,7,7,7,7,7,1,0,11,11,11,11,11
+;.byte 0,0,0,0,0,0,0,0,0,0,0,11,11,11,11,11
 
 metatiles:
 .byte 0,0,0,0,0
@@ -385,19 +402,9 @@ main:
     adc #1
     sta frame_counter
 
-    lda scroll_x
-    adc #1
-    cmp scroll_x
-    sta scroll_x
-    bcs :+
-        lda scroll_nmt
-        eor #%00000001
-        sta scroll_nmt
-    :
-
     jsr controller
     jsr movement
-    lda player_pos_x
+    jsr move_camera
 
 @draw:
     jsr draw_player
@@ -405,7 +412,40 @@ main:
 
 	jmp @loop
 
+move_camera:
+    lda scroll_x
+    clc
+    adc #0
+    cmp scroll_x
+    sta scroll_x
+    bcs :+
+        lda scroll_nmt
+        eor #%00000001
+        sta scroll_nmt
+    :
+    rts
+
 draw_player:
+    ; see if we can skip drawing the player because it's off screen
+    lda player_pos_x
+    sec
+    sbc scroll_x
+    cmp player_pos_x ; if underflow, nametable bits must be different to continue
+    beq @skip_bcs
+    bcs :+
+        @skip_bcs:
+        lda player_nmt_x
+        eor scroll_nmt
+        beq @hide_player
+        jmp :++
+    :
+        ; if nothing, nametable bits must be same to continue
+        lda player_nmt_x
+        eor scroll_nmt
+        bne @hide_player
+    :
+
+
     lda player_pos_y
     sec
     sbc #1
@@ -416,47 +456,6 @@ draw_player:
     sta oam + (4 * 0) + 0
     sta oam + (4 * 1) + 0
 
-
-
-jmp @after
-    ; see if we can skip drawing the player because it's off screen
-    lda player_pos_x
-    sec
-    sbc scroll_x
-    cmp player_pos_x ; if underflow, nametable bits must be different to continue
-    bcs :+
-        lda player_status
-        clc
-        ror
-        eor scroll_nmt
-        beq @end_position_application
-        jmp :++
-    :
-        ; if nothing, nametable bits must be same to continue
-        lda player_status
-        clc
-        ror
-        eor scroll_nmt
-        bne @end_position_application
-    :
-@after:
-
-
-;;;;;;;;;;;;;;;;;;;;;;;;;PUT WHEN VELOCITY IS BEING APPLIED
-    lda player_pos_x
-    adc #1
-    cmp player_pos_x
-    sta player_pos_x
-    bcs :+
-        lda player_status
-        eor #%00000010
-        sta player_status
-    :
-;;;;;;;;;;;;;;;;;;;;;;;;;
-
-
-
-
     lda player_status
     and #%00000001
     cmp #0
@@ -482,8 +481,17 @@ jmp @after
         sta oam + (4 * 1) + 3
         sta oam + (4 * 3) + 3
     :
+    jmp @end_hide_player
 
-    @end_position_application:
+    @hide_player:
+
+    lda #250
+    sta oam + (4 * 2) + 0
+    sta oam + (4 * 3) + 0
+    sta oam + (4 * 0) + 0
+    sta oam + (4 * 1) + 0
+
+    @end_hide_player:
 
     lda player_status
     and #%10000000
@@ -709,6 +717,7 @@ movement:
     bne :+
         ; 0: right
         lda player_vel_x
+        sta var_o ; store initial velocity in o
         and #%01111111
         clc
         ror
@@ -721,6 +730,12 @@ movement:
         clc
         adc player_pos_x
         sta player_pos_x ; add pixels
+        bcc @end_pixel_overflow_right
+            lda player_nmt_x
+            eor #%00000001
+            sta player_nmt_x
+        @end_pixel_overflow_right:
+
 
         lda player_vel_x
         ; A contains signed subpixels
@@ -732,15 +747,22 @@ movement:
         sta player_subpos_x
         beq @end_add_subpos
         bcs @end_add_subpos ; so skip if subpos is smaller than result
-            ldx player_pos_x
-            inx
-            stx player_pos_x
+            lda player_pos_x
+            clc
+            adc #1
+            sta player_pos_x
+            bcc @end_subpixel_overflow_right
+                lda player_nmt_x
+                eor #%00000001
+                sta player_nmt_x
+            @end_subpixel_overflow_right:
         @end_add_subpos:
 
         jmp :++
     :
         ; 1: left
         lda player_vel_x
+        sta var_o
         sec
         ror
         sec
@@ -751,10 +773,23 @@ movement:
         ror
         ora #%10000000
         clc
-        adc #1
-        clc
         adc player_pos_x
         sta player_pos_x ; add pixels
+        bcs @end_pixel_overflow_left
+            lda player_nmt_x
+            eor #%00000001
+            sta player_nmt_x
+        @end_pixel_overflow_left:
+        ;                               :|
+        lda player_pos_x
+        clc
+        adc #1
+        sta player_pos_x ; add... correction?
+        bcc @end_correction
+            lda player_nmt_x
+            eor #%00000001
+            sta player_nmt_x
+        @end_correction:
 
 
         lda player_vel_x
@@ -767,13 +802,23 @@ movement:
         sta player_subpos_x
         beq @end_sub_subpos
         bcc @end_sub_subpos ; so skip if subpos is bigger than result
-            ldx player_pos_x
-            dex
-            stx player_pos_x
+            lda player_pos_x
+            sec
+            sbc #1
+            sta player_pos_x
+            bcs @end_subpixel_overflow_left
+                lda player_nmt_x
+                eor #%00000001
+                sta player_nmt_x
+            @end_subpixel_overflow_left:
         @end_sub_subpos:
     :
 
 
+
+
+
+
     ; load x pos, filter blocks, check up and down
     
     lda player_vel_y