From 90267e4646234d464ee25b3d21fb6cb13217b9bb Mon Sep 17 00:00:00 2001
From: Lucas Scharenbroich <lscharen@prowestgis.com>
Date: Sat, 20 Nov 2021 20:33:27 -0600
Subject: [PATCH] Test updating tile ID in UpdateSprite for a run sequence.

---
 demos/sprites/App.Main.s | 23 ++++++++++++++++++++---
 src/Render.s             |  8 +++-----
 2 files changed, 23 insertions(+), 8 deletions(-)

diff --git a/demos/sprites/App.Main.s b/demos/sprites/App.Main.s
index 6182ce4..0223382 100644
--- a/demos/sprites/App.Main.s
+++ b/demos/sprites/App.Main.s
@@ -411,8 +411,6 @@ UpdatePlayerLocal
 ; Simple updates with gravity and collisions.  It's important that eveything in this
 ; subroutine be done against 
 UpdatePlayerPos
-            stz  tmp0                        ; build up some flags
-
             stz  PlayerStanding
             lda  PlayerYVel
             bmi  :no_ground_check
@@ -490,13 +488,32 @@ UpdatePlayerPos
             txa
             ora  LastHFlip
             ora  #SPRITE_ID
-            tax
+            sta  SpriteFrame
+
+; If the player is standing and XVel != 0, pick a frame
+            lda  PlayerStanding
+            beq  :frame
+            lda  PlayerXVel
+            beq  :frame
+
+            jsl  GetVBLTicks
+            and  #$0003
+            inc
+            and  #$0003
+            asl
+            adc  SpriteFrame
+            sta  SpriteFrame
+:frame
+            ldx  SpriteFrame
+
             lda  PlayerID
             jsl  UpdateSprite                          ; Change the tile ID and / or flags
 
             rts
 
 LastHFlip       dw   0
+SpriteFrame     ds   2
+
 ; X = coordinate
 ; Y = coordinate
 GetTileAt
diff --git a/src/Render.s b/src/Render.s
index 9285331..668fca6 100644
--- a/src/Render.s
+++ b/src/Render.s
@@ -78,9 +78,7 @@ _Render
             jsr   _ApplyBG0XPosPre
             jsr   _ApplyBG1XPosPre
 
-            nop
             jsr   _RenderSprites      ; Once the BG0 X and Y positions are committed, update sprite data
-            nop
 
             jsr   _UpdateBG0TileMap   ; and the tile maps.  These subroutines build up a list of tiles
             jsr   _UpdateBG1TileMap   ; that need to be updated in the code field
@@ -122,9 +120,9 @@ _Render
             ldy   ScreenHeight
             jsr   _BltRange
 
-            ldx   #0
-            ldy   ScreenHeight
-            jsr   _BltSCB
+;            ldx   #0
+;            ldy   ScreenHeight
+;            jsr   _BltSCB
 
             lda   StartY              ; Restore the fields back to their original state
             ldx   ScreenHeight