From 162a0df9221f3d89d6396f006b490c1ea6c96ff5 Mon Sep 17 00:00:00 2001
From: Connor McLaughlin <mclaughc@outlook.com>
Date: Fri, 4 Oct 2019 20:48:29 +1000
Subject: [PATCH] Frontend: Display emulation speed

---
 src/core/system.cpp               | 14 ++++++++++++--
 src/core/system.h                 |  2 ++
 src/duckstation/sdl_interface.cpp | 17 ++++++++++++++++-
 src/duckstation/sdl_interface.h   |  2 ++
 4 files changed, 32 insertions(+), 3 deletions(-)

diff --git a/src/core/system.cpp b/src/core/system.cpp
index 7727378f7..d61b1b9f8 100644
--- a/src/core/system.cpp
+++ b/src/core/system.cpp
@@ -81,6 +81,13 @@ bool System::Initialize()
 
 bool System::DoState(StateWrapper& sw)
 {
+  if (!sw.DoMarker("System"))
+    return false;
+
+  sw.Do(&m_frame_number);
+  sw.Do(&m_internal_frame_number);
+  sw.Do(&m_global_tick_counter);
+
   if (!sw.DoMarker("CPU") || !m_cpu->DoState(sw))
     return false;
 
@@ -127,6 +134,8 @@ void System::Reset()
   m_spu->Reset();
   m_mdec->Reset();
   m_frame_number = 1;
+  m_internal_frame_number = 0;
+  m_global_tick_counter = 0;
 }
 
 bool System::LoadState(ByteStream* state)
@@ -268,10 +277,11 @@ bool System::SetExpansionROM(const char* filename)
 
 void System::Synchronize()
 {
-  m_cpu->ResetDowncount();
-
   const TickCount pending_ticks = m_cpu->GetPendingTicks();
   m_cpu->ResetPendingTicks();
+  m_cpu->ResetDowncount();
+
+  m_global_tick_counter += static_cast<u32>(pending_ticks);
 
   m_gpu->Execute(pending_ticks);
   m_timers->AddSystemTicks(pending_ticks);
diff --git a/src/core/system.h b/src/core/system.h
index 399257410..d81c8aec9 100644
--- a/src/core/system.h
+++ b/src/core/system.h
@@ -36,6 +36,7 @@ public:
 
   u32 GetFrameNumber() const { return m_frame_number; }
   u32 GetInternalFrameNumber() const { return m_internal_frame_number; }
+  u32 GetGlobalTickCounter() const { return m_global_tick_counter; }
   void IncrementFrameNumber() { m_frame_number++; }
   void IncrementInternalFrameNumber() { m_internal_frame_number++; }
 
@@ -79,6 +80,7 @@ private:
   std::unique_ptr<MDEC> m_mdec;
   u32 m_frame_number = 1;
   u32 m_internal_frame_number = 1;
+  u32 m_global_tick_counter = 0;
 
   Settings m_settings;
 };
diff --git a/src/duckstation/sdl_interface.cpp b/src/duckstation/sdl_interface.cpp
index 284367af1..604406dad 100644
--- a/src/duckstation/sdl_interface.cpp
+++ b/src/duckstation/sdl_interface.cpp
@@ -562,7 +562,17 @@ void SDLInterface::RenderMainMenuBar()
     ImGui::EndMenu();
   }
 
-  ImGui::SetCursorPosX(ImGui::GetIO().DisplaySize.x - 170.0f);
+  ImGui::SetCursorPosX(ImGui::GetIO().DisplaySize.x - 205.0f);
+
+  const u32 rounded_speed = static_cast<u32>(std::round(m_speed));
+  if (m_speed < 90.0f)
+    ImGui::TextColored(ImVec4(1.0f, 0.4f, 0.4f, 1.0f), "%u%%", rounded_speed);
+  else if (m_speed < 110.0f)
+    ImGui::TextColored(ImVec4(1.0f, 1.0f, 1.0f, 1.0f), "%u%%", rounded_speed);
+  else
+    ImGui::TextColored(ImVec4(0.4f, 1.0f, 0.4f, 1.0f), "%u%%", rounded_speed);
+
+  ImGui::SetCursorPosX(ImGui::GetIO().DisplaySize.x - 165.0f);
   ImGui::Text("FPS: %.2f", m_fps);
 
   ImGui::SetCursorPosX(ImGui::GetIO().DisplaySize.x - 80.0f);
@@ -680,6 +690,11 @@ void SDLInterface::Run()
         m_fps = static_cast<float>(
           static_cast<double>(m_system->GetInternalFrameNumber() - m_last_internal_frame_number) / time);
         m_last_internal_frame_number = m_system->GetInternalFrameNumber();
+        m_speed =
+          static_cast<float>(static_cast<double>(m_system->GetGlobalTickCounter() - m_last_global_tick_counter) /
+                             (static_cast<double>(MASTER_CLOCK) * time)) *
+          100.0f;
+        m_last_global_tick_counter = m_system->GetGlobalTickCounter();
         m_fps_timer.Reset();
       }
     }
diff --git a/src/duckstation/sdl_interface.h b/src/duckstation/sdl_interface.h
index aebdc0a3f..c5eb8166f 100644
--- a/src/duckstation/sdl_interface.h
+++ b/src/duckstation/sdl_interface.h
@@ -84,8 +84,10 @@ private:
 
   float m_vps = 0.0f;
   float m_fps = 0.0f;
+  float m_speed = 1.0f;
   u32 m_last_frame_number = 0;
   u32 m_last_internal_frame_number = 0;
+  u32 m_last_global_tick_counter = 0;
   Timer m_fps_timer;
 
   // UI options