From 2d2e0c7e311a8ce768d2141d73a235d9aaddd992 Mon Sep 17 00:00:00 2001
From: pjgat09 <pjgat09@gmail.com>
Date: Wed, 31 Oct 2012 23:42:18 +0000
Subject: [PATCH] A2600: Resetting players before hsyncCnt 76 has apparently
 has strange results. I borrowed these changes from EMU7800. This seems to fix
 glitches with Frostbite.

---
 BizHawk.Emulation/Consoles/Atari/2600/TIA.cs | 51 +++++++++++++++++++-
 1 file changed, 49 insertions(+), 2 deletions(-)

diff --git a/BizHawk.Emulation/Consoles/Atari/2600/TIA.cs b/BizHawk.Emulation/Consoles/Atari/2600/TIA.cs
index eda9815ee6..38a479ce36 100644
--- a/BizHawk.Emulation/Consoles/Atari/2600/TIA.cs
+++ b/BizHawk.Emulation/Consoles/Atari/2600/TIA.cs
@@ -1169,11 +1169,58 @@ namespace BizHawk.Emulation.Consoles.Atari
 			}
 			else if (maskedAddr == 0x10) // RESP0
 			{
-				player0.resetCnt = 0;
+				// Borrowed from EMU7800. Apparently resetting between 68 and 76 has strange results. 
+				if (hsyncCnt < 69)
+				{
+					player0.hPosCnt = 0;
+					player0.resetCnt = 0;
+					player0.reset = true;
+				}
+				else if (hsyncCnt == 69)
+				{
+					player0.resetCnt = 3;
+				}
+				else if (hsyncCnt == 72)
+				{
+					player0.resetCnt = 2;
+				}
+				else if (hsyncCnt == 75)
+				{
+					player0.resetCnt = 1;
+				}
+				else
+				{
+					player0.resetCnt = 0;
+				}
+				//player0.resetCnt = 0;
 			}
 			else if (maskedAddr == 0x11) // RESP1
 			{
-				player1.resetCnt = 0;
+				// Borrowed from EMU7800. Apparently resetting between 68 and 76 has strange results. 
+				// This fixes some graphic glitches with Frostbite
+				if (hsyncCnt < 69)
+				{
+					player1.hPosCnt = 0;
+					player1.resetCnt = 0;
+					player1.reset = true;
+				}
+				else if (hsyncCnt == 69)
+				{
+					player1.resetCnt = 3;
+				}
+				else if (hsyncCnt == 72)
+				{
+					player1.resetCnt = 2;
+				}
+				else if (hsyncCnt == 75)
+				{
+					player1.resetCnt = 1;
+				}
+				else
+				{
+					player1.resetCnt = 0;
+				}
+				//player1.resetCnt = 0;
 			}
 			else if (maskedAddr == 0x12) // RESM0
 			{