From 3004026db848c5478a1905c7e76d80952e62da40 Mon Sep 17 00:00:00 2001
From: Robin Kertels <robin.kertels@gmail.com>
Date: Tue, 29 Mar 2022 22:51:59 +0200
Subject: [PATCH] [d3d9] Only bind RT if we actually write to it

The alternative render path for shadow maps in Dead Space relies on this.
---
 src/d3d9/d3d9_device.cpp | 26 +++++++++++++++++++++-----
 1 file changed, 21 insertions(+), 5 deletions(-)

diff --git a/src/d3d9/d3d9_device.cpp b/src/d3d9/d3d9_device.cpp
index d4140de5f..1ca50924a 100644
--- a/src/d3d9/d3d9_device.cpp
+++ b/src/d3d9/d3d9_device.cpp
@@ -1795,8 +1795,9 @@ namespace dxvk {
       return m_recorder->SetRenderState(State, Value);
 
     auto& states = m_state.renderStates;
+    DWORD old = states[State];
 
-    bool changed = states[State] != Value;
+    bool changed = old != Value;
 
     if (likely(changed)) {
       const bool oldClipPlaneEnabled = IsClipPlaneEnabled();
@@ -1880,19 +1881,31 @@ namespace dxvk {
           break;
 
         case D3DRS_COLORWRITEENABLE:
-          UpdateActiveRTs(0);
+          if (likely(!old != !Value)) {
+            m_flags.set(D3D9DeviceFlag::DirtyFramebuffer);
+            UpdateActiveRTs(0);
+          }
           m_flags.set(D3D9DeviceFlag::DirtyBlendState);
           break;
         case D3DRS_COLORWRITEENABLE1:
-          UpdateActiveRTs(1);
+          if (likely(!old != !Value && m_state.renderTargets[1] != nullptr)) {
+            m_flags.set(D3D9DeviceFlag::DirtyFramebuffer);
+            UpdateActiveRTs(1);
+          }
           m_flags.set(D3D9DeviceFlag::DirtyBlendState);
           break;
         case D3DRS_COLORWRITEENABLE2:
-          UpdateActiveRTs(2);
+          if (likely(!old != !Value && m_state.renderTargets[2] != nullptr)) {
+            m_flags.set(D3D9DeviceFlag::DirtyFramebuffer);
+            UpdateActiveRTs(2);
+          }
           m_flags.set(D3D9DeviceFlag::DirtyBlendState);
           break;
         case D3DRS_COLORWRITEENABLE3:
-          UpdateActiveRTs(3);
+          if (likely(!old != !Value && m_state.renderTargets[3] != nullptr)) {
+            m_flags.set(D3D9DeviceFlag::DirtyFramebuffer);
+            UpdateActiveRTs(3);
+          }
           m_flags.set(D3D9DeviceFlag::DirtyBlendState);
           break;
 
@@ -5555,6 +5568,9 @@ namespace dxvk {
       else if (unlikely(sampleCount != rtImageInfo.sampleCount))
         continue;
 
+      if (!m_state.renderStates[ColorWriteIndex(i)])
+        continue;
+
       attachments.color[i] = {
         m_state.renderTargets[i]->GetRenderTargetView(srgb),
         m_state.renderTargets[i]->GetRenderTargetLayout() };