From ff4c1c9cf679ea4658d91ddb0f975c42f5ba76c2 Mon Sep 17 00:00:00 2001
From: StapleButter <thetotalworm@gmail.com>
Date: Sat, 4 Mar 2017 02:37:39 +0100
Subject: [PATCH] support 16-bit writes to rotscale reference point registers

---
 GPU2D.cpp      | 44 ++++++++++++++++++++++++++++++++++++++++----
 melonDS.depend |  2 +-
 2 files changed, 41 insertions(+), 5 deletions(-)

diff --git a/GPU2D.cpp b/GPU2D.cpp
index e819b8fc..1398d6b1 100644
--- a/GPU2D.cpp
+++ b/GPU2D.cpp
@@ -177,11 +177,47 @@ void GPU2D::Write16(u32 addr, u16 val)
     case 0x022: BGRotB[0] = val; return;
     case 0x024: BGRotC[0] = val; return;
     case 0x026: BGRotD[0] = val; return;
+    case 0x028:
+        BGXRef[0] = (BGXRef[0] & 0xFFFF0000) | val;
+        if (GPU::VCount < 192) BGXRefInternal[0] = BGXRef[0];
+        return;
+    case 0x02A:
+        if (val & 0x0800) val |= 0xF000;
+        BGXRef[0] = (BGXRef[0] & 0xFFFF) | (val << 16);
+        if (GPU::VCount < 192) BGXRefInternal[0] = BGXRef[0];
+        return;
+    case 0x02C:
+        BGYRef[0] = (BGYRef[0] & 0xFFFF0000) | val;
+        if (GPU::VCount < 192) BGYRefInternal[0] = BGYRef[0];
+        return;
+    case 0x02E:
+        if (val & 0x0800) val |= 0xF000;
+        BGYRef[0] = (BGYRef[0] & 0xFFFF) | (val << 16);
+        if (GPU::VCount < 192) BGYRefInternal[0] = BGYRef[0];
+        return;
 
     case 0x030: BGRotA[1] = val; return;
     case 0x032: BGRotB[1] = val; return;
     case 0x034: BGRotC[1] = val; return;
     case 0x036: BGRotD[1] = val; return;
+    case 0x038:
+        BGXRef[1] = (BGXRef[1] & 0xFFFF0000) | val;
+        if (GPU::VCount < 192) BGXRefInternal[1] = BGXRef[1];
+        return;
+    case 0x03A:
+        if (val & 0x0800) val |= 0xF000;
+        BGXRef[1] = (BGXRef[1] & 0xFFFF) | (val << 16);
+        if (GPU::VCount < 192) BGXRefInternal[1] = BGXRef[1];
+        return;
+    case 0x03C:
+        BGYRef[1] = (BGYRef[1] & 0xFFFF0000) | val;
+        if (GPU::VCount < 192) BGYRefInternal[1] = BGYRef[1];
+        return;
+    case 0x03E:
+        if (val & 0x0800) val |= 0xF000;
+        BGYRef[1] = (BGYRef[1] & 0xFFFF) | (val << 16);
+        if (GPU::VCount < 192) BGYRefInternal[1] = BGYRef[1];
+        return;
 
     case 0x050: BlendCnt = val; return;
     case 0x052:
@@ -213,23 +249,23 @@ void GPU2D::Write32(u32 addr, u32 val)
     case 0x028:
         if (val & 0x08000000) val |= 0xF0000000;
         BGXRef[0] = val;
-        if (GPU::VCount < 192) BGXRefInternal[0] = val;
+        if (GPU::VCount < 192) BGXRefInternal[0] = BGXRef[0];
         return;
     case 0x02C:
         if (val & 0x08000000) val |= 0xF0000000;
         BGYRef[0] = val;
-        if (GPU::VCount < 192) BGYRefInternal[0] = val;
+        if (GPU::VCount < 192) BGYRefInternal[0] = BGYRef[0];
         return;
 
     case 0x038:
         if (val & 0x08000000) val |= 0xF0000000;
         BGXRef[1] = val;
-        if (GPU::VCount < 192) BGXRefInternal[1] = val;
+        if (GPU::VCount < 192) BGXRefInternal[1] = BGXRef[1];
         return;
     case 0x03C:
         if (val & 0x08000000) val |= 0xF0000000;
         BGYRef[1] = val;
-        if (GPU::VCount < 192) BGYRefInternal[1] = val;
+        if (GPU::VCount < 192) BGYRefInternal[1] = BGYRef[1];
         return;
 
     case 0x064:
diff --git a/melonDS.depend b/melonDS.depend
index d1fe9714..b158daca 100644
--- a/melonDS.depend
+++ b/melonDS.depend
@@ -87,7 +87,7 @@
 	"NDS.h"
 	"SPI.h"
 
-1488589055 source:c:\documents\sources\melonds\gpu2d.cpp
+1488590400 source:c:\documents\sources\melonds\gpu2d.cpp
 	<stdio.h>
 	<string.h>
 	"NDS.h"