From a20c596b9c8da408f725a66ebf43a6fcaf95cab2 Mon Sep 17 00:00:00 2001
From: Wei-ju Wu <weiju.wu@gmail.com>
Date: Wed, 27 Jan 2016 21:01:15 -0800
Subject: [PATCH] sprite fix added for Kickstart >= 3.0

---
 hardware/.gitignore |  1 +
 hardware/startup.c  | 58 +++++++++++++++++++++++++++++++++++++--------
 2 files changed, 49 insertions(+), 10 deletions(-)
 create mode 100644 hardware/.gitignore

diff --git a/hardware/.gitignore b/hardware/.gitignore
new file mode 100644
index 0000000..efcfc5a
--- /dev/null
+++ b/hardware/.gitignore
@@ -0,0 +1 @@
+startup
diff --git a/hardware/startup.c b/hardware/startup.c
index b1e74d8..b123cab 100644
--- a/hardware/startup.c
+++ b/hardware/startup.c
@@ -6,6 +6,7 @@
 #include <clib/intuition_protos.h>
 #include <exec/execbase.h>
 #include <graphics/gfxbase.h>
+#include <graphics/videocontrol.h>
 #include <stdio.h>
 
 /*
@@ -27,6 +28,7 @@ void waitmouse() = "waitmouse:\n\tbtst\t#6,$bfe001\n\tbne\twaitmouse";
 #define EXEC_BASE (4L)
 #define TASK_PRIORITY 127
 #define VFREQ_PAL 50
+#define WB_SCREEN_NAME "Workbench"
 
 static UWORD __chip coplist_pal[] = {
     0x100, 0x200,        // otherwise no display!
@@ -50,6 +52,39 @@ static UWORD __chip coplist_ntsc[] = {
     0xffff, 0xfffe
 };
 
+static struct Screen *wbscreen;
+static ULONG oldresolution;
+
+static void ApplySpriteFix()
+{
+    if (wbscreen = LockPubScreen(WB_SCREEN_NAME)) {
+        struct TagItem video_control_tags[] = {
+            {VTAG_SPRITERESN_GET, SPRITERESN_ECS},
+            {TAG_DONE, 0}
+        };
+        struct TagItem video_control_tags2[] = {
+            {VTAG_SPRITERESN_SET, SPRITERESN_140NS},
+            {TAG_DONE, 0}
+        };
+        VideoControl(wbscreen->ViewPort.ColorMap, video_control_tags);
+        oldresolution = video_control_tags[0].ti_Data;
+        VideoControl(wbscreen->ViewPort.ColorMap, video_control_tags2);
+        MakeScreen(wbscreen);
+        RethinkDisplay();
+    }
+}
+static void UnapplySpriteFix()
+{
+    if (wbscreen) {
+        struct TagItem video_control_tags[] = {
+            {VTAG_SPRITERESN_SET, oldresolution},
+            {TAG_DONE, 0}
+        };
+        VideoControl(wbscreen->ViewPort.ColorMap, video_control_tags);
+        MakeScreen(wbscreen);
+        UnlockPubScreen(NULL, wbscreen);
+    }
+}
 
 int main(int argc, char **argv)
 {
@@ -57,24 +92,27 @@ int main(int argc, char **argv)
     struct Task *current_task = FindTask(NULL);
     BYTE old_prio = SetTaskPri(current_task, TASK_PRIORITY);
     struct View *current_view = ((struct GfxBase *) GfxBase)->ActiView;
+    UWORD lib_version = ((struct Library *) GfxBase)->lib_Version;
+    BOOL is_pal;
+
     LoadView(NULL);
     WaitTOF();
     WaitTOF();
 
-    // Assuming 1.x, TODO: add handling for >= 2.x
-    // Note: FS-UAE reports 0 this, so essentially, there is no information
-    // for 1.x
-    if (((struct ExecBase *) EXEC_BASE)->VBlankFrequency == VFREQ_PAL) {
-        // Handle PAL
-        printf("PAL: %d\n", (int) ((struct ExecBase *) EXEC_BASE)->VBlankFrequency);
-        custom.cop1lc = (ULONG) coplist_pal;
+    // Kickstart > 3.0: fix sprite bug
+    if (lib_version >= 39) {
+        ApplySpriteFix();
+        is_pal = (((struct GfxBase *) GfxBase)->DisplayFlags & PAL) == PAL;
     } else {
-        // Handle NTSC
-        printf("NTSC: %d\n", (int) ((struct ExecBase *) EXEC_BASE)->VBlankFrequency);
-        custom.cop1lc = (ULONG) coplist_ntsc;
+        // Note: FS-UAE reports 0 this, so essentially, there is no information
+        // for 1.x
+        printf("PAL/NTSC: %d\n", (int) ((struct ExecBase *) EXEC_BASE)->VBlankFrequency);
+        is_pal = ((struct ExecBase *) EXEC_BASE)->VBlankFrequency == VFREQ_PAL;
     }
+    custom.cop1lc = is_pal ? (ULONG) coplist_pal : (ULONG) coplist_ntsc;
 
     waitmouse();
+    if (lib_version >= 39) UnapplySpriteFix();
     LoadView(current_view);
     WaitTOF();
     WaitTOF();