From 807dd726565a2238e2c7f8fb1ede7f30b1147662 Mon Sep 17 00:00:00 2001
From: Philip Rebohle <philip.rebohle@tu-dortmund.de>
Date: Thu, 8 Feb 2018 12:48:54 +0100
Subject: [PATCH] [hud] Use buffer invalidation instead of synchronization

The previously used synchronization may have had a negative impact on
performance, whereas the new approach is similar to what D3D11 apps do.
---
 src/dxvk/hud/dxvk_hud.cpp      | 25 +++++++------------------
 src/dxvk/hud/dxvk_hud.h        |  2 --
 src/dxvk/hud/dxvk_hud_text.cpp |  5 ++++-
 3 files changed, 11 insertions(+), 21 deletions(-)

diff --git a/src/dxvk/hud/dxvk_hud.cpp b/src/dxvk/hud/dxvk_hud.cpp
index 6c893fac..302c1e54 100644
--- a/src/dxvk/hud/dxvk_hud.cpp
+++ b/src/dxvk/hud/dxvk_hud.cpp
@@ -29,9 +29,8 @@ namespace dxvk::hud {
       
     m_hudFps.update();
     
-    this->synchronize();
-    this->updateUniformBuffer();
     this->beginRenderPass(recreateFbo);
+    this->updateUniformBuffer();
     this->renderText();
     this->endRenderPass();
   }
@@ -73,24 +72,13 @@ namespace dxvk::hud {
   }
   
   
-  void Hud::synchronize() {
-    // Wait for previous frame to complete so that we can
-    // safely write to the uniform/vertex buffers. We could
-    // actually avoid this by double-buffering the data, but
-    // it is probably not worth the effort.
-    if (m_syncFence != nullptr) {
-      m_syncFence->wait(
-        std::numeric_limits<uint64_t>::max());
-    }
-  }
-  
-  
   void Hud::updateUniformBuffer() {
     HudUniformData uniformData;
     uniformData.surfaceSize = m_surfaceSize;
     
-    std::memcpy(m_uniformBuffer->mapPtr(0),
-      &uniformData, sizeof(uniformData));
+    auto slice = m_uniformBuffer->allocPhysicalSlice();
+    m_context->invalidateBuffer(m_uniformBuffer, slice);
+    std::memcpy(slice.mapPtr(0), &uniformData, sizeof(uniformData));
   }
   
   
@@ -139,8 +127,9 @@ namespace dxvk::hud {
   
   
   void Hud::endRenderPass() {
-    m_syncFence = m_device->submitCommandList(
-      m_context->endRecording(), nullptr, nullptr);
+    m_device->submitCommandList(
+      m_context->endRecording(),
+      nullptr, nullptr);
   }
   
   
diff --git a/src/dxvk/hud/dxvk_hud.h b/src/dxvk/hud/dxvk_hud.h
index 2b949a6b..1ac256dd 100644
--- a/src/dxvk/hud/dxvk_hud.h
+++ b/src/dxvk/hud/dxvk_hud.h
@@ -68,7 +68,6 @@ namespace dxvk::hud {
     HudTextRenderer       m_textRenderer;
     VkExtent2D            m_surfaceSize = { 0, 0 };
     
-    Rc<DxvkFence>         m_syncFence;
     Rc<DxvkBuffer>        m_uniformBuffer;
     Rc<DxvkImage>         m_renderTarget;
     Rc<DxvkImageView>     m_renderTargetView;
@@ -81,7 +80,6 @@ namespace dxvk::hud {
     
     Rc<DxvkBuffer> createUniformBuffer();
     
-    void synchronize();
     void updateUniformBuffer();
     void beginRenderPass(bool initFbo);
     void endRenderPass();
diff --git a/src/dxvk/hud/dxvk_hud_text.cpp b/src/dxvk/hud/dxvk_hud_text.cpp
index 44b8e0ab..e44a9433 100644
--- a/src/dxvk/hud/dxvk_hud_text.cpp
+++ b/src/dxvk/hud/dxvk_hud_text.cpp
@@ -68,8 +68,11 @@ namespace dxvk::hud {
     const std::string&      text) {
     const size_t vertexIndex = m_vertexIndex;
     
+    auto vertexSlice = m_vertexBuffer->allocPhysicalSlice();
+    context->invalidateBuffer(m_vertexBuffer, vertexSlice);
+    
     HudTextVertex* vertexData = reinterpret_cast<HudTextVertex*>(
-      m_vertexBuffer->mapPtr(vertexIndex * sizeof(HudTextVertex)));
+      vertexSlice.mapPtr(vertexIndex * sizeof(HudTextVertex)));
     
     const float sizeFactor = size / static_cast<float>(g_hudFont.size);