From c0521157f27dac7993c3879f0f0e632dc144a86e Mon Sep 17 00:00:00 2001
From: Peter Ferrie <peter.ferrie@gmail.com>
Date: Fri, 11 Jan 2019 14:32:49 -0800
Subject: [PATCH] GS to init phase

---
 src/constants.a      |  2 +-
 src/pitchdark.init.a | 26 ++++++++++++++++++++------
 src/prodos.mli.a     |  2 +-
 src/ui.artwork.a     | 19 +++++--------------
 4 files changed, 27 insertions(+), 22 deletions(-)

diff --git a/src/constants.a b/src/constants.a
index 9f98b23..e67a745 100644
--- a/src/constants.a
+++ b/src/constants.a
@@ -17,7 +17,7 @@
 ;~7400...... - program data (approximate)
 ;
 
-kPitchDarkBinaryAddress   = $3F2F
+kPitchDarkBinaryAddress   = $3F25
 
 kGameInfoBuffer           = $0800    ; used by LoadGameInfo
 kProDOSFileBuffer         = $1C00    ; 1K buffer for ProDOS MLI calls
diff --git a/src/pitchdark.init.a b/src/pitchdark.init.a
index bde5ec6..568ee0d 100644
--- a/src/pitchdark.init.a
+++ b/src/pitchdark.init.a
@@ -57,19 +57,33 @@
          bne   @nextslot
          dey
          bpl   @matchVidHD
-         dec   PatchVidHD1+1         ; affect branch to pretend IIGS
          lda   #$90
-         sta   PatchVidHD2           ; affect branch to pretend IIGS
-         ldx   #$c1                  ; force exit via fall-through
+         sta   PatchVidHD
+         bne   @setSHR               ; always
+
+@kVidHDID
+         !byte $24, $EA, $4C
 
 @nextslot
          dex
          cpx   #$c0
          bne   @findVidHD
-         beq   +
-@kVidHDID
-         !byte $24, $EA, $4C
+
+;------------------------------------------------------------------------------
+; detect IIGS by running CPU-specific magic
+;------------------------------------------------------------------------------
+
+!cpu 65816
+         rep   #2                    ; clear Z flag on 65816 only
+!cpu 65c02
+         beq   +                     ; skip GS-specific code on non-GS machines (required, will crash on //c, grr)
+@setSHR
+         inc   WeCanHazSHR+1
+         lda   $C029
+         ora   #$40
+         sta   $C029                 ; set GS NEWVIDEO mode to turn off linearize
 +
+
 ;------------------------------------------------------------------------------
 ; clear options script and make checksum invalid
 ;------------------------------------------------------------------------------
diff --git a/src/prodos.mli.a b/src/prodos.mli.a
index 1143cdb..182d667 100644
--- a/src/prodos.mli.a
+++ b/src/prodos.mli.a
@@ -200,7 +200,7 @@ LoadSHRFile
          bcs   close
          phx
 
-PatchVidHD2
+PatchVidHD
          bcs   copyvidhd
 
 !cpu 65816
diff --git a/src/ui.artwork.a b/src/ui.artwork.a
index 66b8cf9..63b7f64 100644
--- a/src/ui.artwork.a
+++ b/src/ui.artwork.a
@@ -23,18 +23,9 @@ kArtworkGSRootDirectory              ; length-prefixed pathname of SHGR graphic
 ; out:   all registers and flags clobbered
 ;------------------------------------------------------------------------------
 DisplayArtwork
-         ldx   #0                    ; set Z flag always
-!cpu 65816
-         rep   #2                    ; clear Z flag on 65816 only
-!cpu 65c02
-PatchVidHD1
-         beq   +                     ; skip GS-specific code on non-GS machines (required, will crash on //c, grr)
-         lda   $C029
-         ora   #$40
-         sta   $C029                 ; set GS NEWVIDEO mode to turn off linearize
-         inx
-
-+        jsr   ResetPath
+WeCanHazSHR
+         ldx   #0                    ; SMC
+         jsr   ResetPath
          +LDADDR kArtworkRootDirectory
          dex
          bne   +
@@ -73,7 +64,7 @@ PatchVidHD1
          plx
          bcs   -
          lda   $C029
-         ora   #$C1
+         ora   #$81
          sta   $C029                 ; set GS NEWVIDEO mode to turn on SHR mode
 
 @waitKey
@@ -85,6 +76,6 @@ PatchVidHD1
          plx
          bne   +
          lda   $C029
-         and   #$3F
+         and   #$7F
          sta   $C029                 ; back to text GS-style
 +        jmp   ClearPendingInput