From 2c1100f0b8296676ff92a37e3bf93245cd74338d Mon Sep 17 00:00:00 2001
From: blondie7575 <qd@quinndunki.com>
Date: Sat, 22 Jul 2023 18:01:10 -0700
Subject: [PATCH] Fixed nasty memory overwrite

If terrain crater was on a mountain top, the crate math tried to compile above max terrain height
---
 GSCats.xcodeproj/project.pbxproj | 6 +++---
 terrain.s                        | 7 ++++++-
 2 files changed, 9 insertions(+), 4 deletions(-)

diff --git a/GSCats.xcodeproj/project.pbxproj b/GSCats.xcodeproj/project.pbxproj
index b5bfc3e..c8a454a 100644
--- a/GSCats.xcodeproj/project.pbxproj
+++ b/GSCats.xcodeproj/project.pbxproj
@@ -59,14 +59,14 @@
 			isa = PBXGroup;
 			children = (
 				70E9D85F1F2BD95400555C19 /* equates.s */,
-				700F21DE1F43E31300D7007D /* input.s */,
+				70E9D8621F2BD95400555C19 /* macros.s */,
 				706DF1641F2D39F700AA6680 /* loader.s */,
 				701E708E2A67844B0030C35D /* loaderGraphics.s */,
 				701E708F2A69CE520030C35D /* loadingBar.s */,
 				701E70902A6A23800030C35D /* sharedGraphics.s */,
 				70E9D8601F2BD95400555C19 /* graphics.s */,
 				70E9D8611F2BD95400555C19 /* gscats.s */,
-				70E9D8621F2BD95400555C19 /* macros.s */,
+				70A80FB01F43D7F200BD34C9 /* gamemanager.s */,
 				7099E3841F41022100182A82 /* gameobject.s */,
 				70F011D123B989B800C8873F /* random.s */,
 				706DF1651F2D4A8100AA6680 /* terrain.s */,
@@ -74,6 +74,7 @@
 				70F011D023B91B2900C8873F /* dirt.s */,
 				70C073091F5BAA3E009844A9 /* collision.s */,
 				70F086A01F4230CB002446C3 /* utility.s */,
+				700F21DE1F43E31300D7007D /* input.s */,
 				700C39C51F2E5CA800C24F9C /* tables.s */,
 				70E266E31F6F262D005AC7E4 /* circleTable.s */,
 				70F0869F1F413A89002446C3 /* player.s */,
@@ -84,7 +85,6 @@
 				700F21DF1F4A364600D7007D /* projectile.s */,
 				705C54E62124B7F300515A6B /* fan.s */,
 				708D1B1E27B9A1A600909AFC /* crosshair.s */,
-				70A80FB01F43D7F200BD34C9 /* gamemanager.s */,
 				70E554C41F807ADB00F3C871 /* spritebank.s */,
 				70E9D8631F2BD95400555C19 /* Makefile */,
 				70BDCBC92006AD5F00CB51F1 /* linkerConfig */,
diff --git a/terrain.s b/terrain.s
index df1803b..38b93da 100644
--- a/terrain.s
+++ b/terrain.s
@@ -294,6 +294,9 @@ compileTerrainDone:
 compileTerrainChunk:
 	tya			; Be extra safe and make sure Y is never negative or we'll spray RAM with terrain data
 	bmi compileTerrainChunkClampZero
+	cpx #MAXTERRAINHEIGHT		; Same caution for top of terrain
+	beq compileTerrainChunkResume
+	bcs compileTerrainChunkClampTop
 
 compileTerrainChunkResume:
 	stx SCRATCHL
@@ -309,7 +312,6 @@ compileTerrainChunkResume:
 
 compileTerrainChunkLoop:
 	sty PARAML1
-;HARDBRK
 	jsr compileTerrainRow
 	iny
 	cpy SCRATCHL
@@ -328,6 +330,9 @@ compileTerrainChunkClampZero:
 	ldy #0
 	bra compileTerrainChunkResume
 
+compileTerrainChunkClampTop:
+	ldx #MAXTERRAINHEIGHT
+	bra compileTerrainChunkResume
 
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 ; compileTerrainRow