GPU: Tweaks to ODE handling

Fixes Team Buddies and The Next Tetris.

src/core/gpu.cpp

@@ -162,6 +162,7 @@ bool GPU::DoState(StateWrapper& sw)
   sw.Do(&m_crtc_state.in_hblank);
   sw.Do(&m_crtc_state.in_vblank);
   sw.Do(&m_crtc_state.interlaced_field);
+  sw.Do(&m_crtc_state.interlaced_display_field);
   sw.Do(&m_crtc_state.active_line_lsb);
 
   sw.Do(&m_blitter_state);
@@ -734,10 +735,10 @@ void GPU::CRTCTickEvent(TickCount ticks)
         System::FrameDone();
 
         // switch fields early. this is needed so we draw to the correct one.
-        if (m_GPUSTAT.vertical_interlace)
+        if (m_GPUSTAT.InInterleaved480iMode())
-          m_crtc_state.interlaced_field ^= 1u;
+          m_crtc_state.interlaced_display_field = m_crtc_state.interlaced_field ^ 1u;
         else
-          m_crtc_state.interlaced_field = 0;
+          m_crtc_state.interlaced_display_field = 0;
       }
 
       g_timers.SetGate(HBLANK_TIMER_INDEX, new_vblank);
@@ -749,15 +750,20 @@ void GPU::CRTCTickEvent(TickCount ticks)
     {
       // start the new frame
       m_crtc_state.current_scanline = 0;
+      if (m_GPUSTAT.vertical_interlace)
+        m_crtc_state.interlaced_field ^= 1u;
+      else
+        m_crtc_state.interlaced_field = 0;
     }
   }
 
   // alternating even line bit in 240-line mode
-  if (m_GPUSTAT.vertical_interlace)
+  if (m_GPUSTAT.InInterleaved480iMode())
   {
     m_crtc_state.active_line_lsb =
-      ConvertToBoolUnchecked((m_crtc_state.regs.Y + BoolToUInt32(m_crtc_state.interlaced_field)) & u32(1));
+      Truncate8((m_crtc_state.regs.Y + BoolToUInt32(m_crtc_state.interlaced_display_field)) & u32(1));
-    m_GPUSTAT.display_line_lsb = m_crtc_state.active_line_lsb && !m_crtc_state.in_vblank;
+    m_GPUSTAT.display_line_lsb = ConvertToBoolUnchecked(
+      (m_crtc_state.regs.Y + (BoolToUInt8(m_crtc_state.in_vblank) ^ m_crtc_state.interlaced_display_field)) & u32(1));
   }
   else
   {

src/core/gpu.h

@@ -513,6 +513,11 @@ protected:
       static constexpr u32 ACTIVE = (1 << 19) | (1 << 22);
       return ((bits & MASK) == ACTIVE);
     }
+    bool InInterleaved480iMode() const
+    {
+      static constexpr u32 ACTIVE = (1 << 19) | (1 << 22);
+      return ((bits & ACTIVE) == ACTIVE);
+    }
 
     // During transfer/render operations, if ((dst_pixel & mask_and) == 0) { pixel = src_pixel | mask_or }
     u16 GetMaskAND() const
@@ -694,6 +699,7 @@ protected:
     bool in_vblank;
 
     u8 interlaced_field; // 0 = odd, 1 = even
+    u8 interlaced_display_field;
     u8 active_line_lsb;
   } m_crtc_state = {};
 

src/core/system.cpp

@@ -227,7 +227,7 @@ bool RecreateGPU(GPURenderer renderer)
   // save current state
   std::unique_ptr<ByteStream> state_stream = ByteStream_CreateGrowableMemoryStream();
   StateWrapper sw(state_stream.get(), StateWrapper::Mode::Write);
-  const bool state_valid = g_gpu->DoState(sw) && TimingEvents::DoState(sw, TimingEvents::GetGlobalTickCounter());
+  const bool state_valid = g_gpu->DoState(sw) && TimingEvents::DoState(sw);
   if (!state_valid)
     Log_ErrorPrintf("Failed to save old GPU state when switching renderers");
 
@@ -247,7 +247,7 @@ bool RecreateGPU(GPURenderer renderer)
     sw.SetMode(StateWrapper::Mode::Read);
     g_gpu->RestoreGraphicsAPIState();
     g_gpu->DoState(sw);
-    TimingEvents::DoState(sw, TimingEvents::GetGlobalTickCounter());
+    TimingEvents::DoState(sw);
     g_gpu->ResetGraphicsAPIState();
   }
 
@@ -540,13 +540,9 @@ bool DoState(StateWrapper& sw)
   if (!sw.DoMarker("System"))
     return false;
 
-  // TODO: Move this into timing state
-  u32 global_tick_counter = TimingEvents::GetGlobalTickCounter();
-
   sw.Do(&s_region);
   sw.Do(&s_frame_number);
   sw.Do(&s_internal_frame_number);
-  sw.Do(&global_tick_counter);
 
   if (!sw.DoMarker("CPU") || !CPU::DoState(sw))
     return false;
@@ -584,7 +580,7 @@ bool DoState(StateWrapper& sw)
   if (!sw.DoMarker("SIO") || !g_sio.DoState(sw))
     return false;
 
-  if (!sw.DoMarker("Events") || !TimingEvents::DoState(sw, global_tick_counter))
+  if (!sw.DoMarker("Events") || !TimingEvents::DoState(sw))
     return false;
 
   return !sw.HasError();

src/core/timing_event.cpp

@@ -172,12 +172,12 @@ void RunEvents()
   UpdateCPUDowncount();
 }
 
-bool DoState(StateWrapper& sw, u32 global_tick_counter)
+bool DoState(StateWrapper& sw)
 {
+  sw.Do(&s_global_tick_counter);
+
   if (sw.IsReading())
   {
-    s_global_tick_counter = global_tick_counter;
-
     // Load timestamps for the clock events.
     // Any oneshot events should be recreated by the load state method, so we can fix up their times here.
     u32 event_count = 0;

src/core/timing_event.h

@@ -79,7 +79,7 @@ std::unique_ptr<TimingEvent> CreateTimingEvent(std::string name, TickCount perio
                                                TimingEventCallback callback, bool activate);
 
 /// Serialization.
-bool DoState(StateWrapper& sw, u32 global_tick_counter);
+bool DoState(StateWrapper& sw);
 
 void RunEvents();