Implemenmted rendering priorities

Desktop/Form1.cs

@@ -1,22 +1,26 @@
+using System.Diagnostics;
+using System.Drawing.Imaging;
 using System.Reflection;
 using System.Reflection.PortableExecutable;
-using Core;
-using System.Threading.Tasks;
-using System.Drawing.Imaging;
 using System.Runtime.InteropServices;
+using System.Threading.Tasks;
 using System.Windows.Forms;
+using Core;
 
 namespace Desktop
 {
-    public partial class Form1 : Form
+    public partial class ParsonsForm1 : Form
     {
         private SmsMachine _machine = null!;
         private DebuggerForm _debugger;
         private Bitmap _screenBitmap = new Bitmap(256, 192, PixelFormat.Format32bppArgb);
-
         private Task _emulatorTask;
-
-
+        private double TargetFrameTime = 16.667f;
+        public int TotalFrameCount = 0;
+        public double FrameTime { get; private set; } = 0;
+        public double FramesPerSecond { get; private set; } = 0;
+        private string _currentRomName = "No ROM";
+        private Stopwatch _stopwatch = new System.Diagnostics.Stopwatch();
         public bool IsRunning { get; private set; } = false;
 
         public ushort? Breakpoint
@@ -25,9 +29,10 @@ namespace Desktop
             set { if (_machine != null) _machine.Breakpoint = value; }
         }
 
-        public Form1()
+        public ParsonsForm1()
         {
             InitializeComponent();
+            this.Text = $"Parsons Master System 2026 - {_currentRomName}";
             _machine = new SmsMachine();
 
             PopulateIncludedRomsMenu();
@@ -46,32 +51,81 @@ namespace Desktop
 
             // Update the PictureBox
             pbScreen.Image = _screenBitmap;
+            TotalFrameCount++;
         }
 
         public void StartEmulator()
         {
             if (IsRunning) return;
             IsRunning = true;
+            TotalFrameCount = 0;
+
+            double TargetFrameTime = 1000.0 / 60.0;
+
             _emulatorTask = Task.Run(() =>
             {
+                _stopwatch.Restart();
+
+                double nextFrameTargetTime = _stopwatch.Elapsed.TotalMilliseconds + TargetFrameTime;
+                double lastFpsUpdate = _stopwatch.Elapsed.TotalMilliseconds;
+                int framesThisSecond = 0;
+
                 while (IsRunning)
                 {
+                    // Mark exactly when the emulator starts thinking
+                    double frameStartTime = _stopwatch.Elapsed.TotalMilliseconds;
+
+                    // 1. Do the heavy lifting (Z80 and VDP)
                     _machine.RunFrame();
 
-                    Invoke((System.Windows.Forms.MethodInvoker)delegate { DrawScreen(); });
+                    // 2. FIRE AND FORGET! Tell Windows to draw, but DO NOT WAIT for it to finish!
+                    BeginInvoke((System.Windows.Forms.MethodInvoker)delegate { DrawScreen(); });
 
-                    // Safety catch: If we hit a breakpoint while running, stop the loop!
+                    // 3. Safety catch
                     if (_machine.Breakpoint.HasValue && _machine.Cpu.PC == _machine.Breakpoint.Value)
                     {
                         IsRunning = false;
-
-                        // Optional: Force the debugger UI to update immediately so you see it!
-                        Invoke((System.Windows.Forms.MethodInvoker)delegate { _debugger?.uiUpdateTimer_Tick(null, EventArgs.Empty); });
+                        BeginInvoke((System.Windows.Forms.MethodInvoker)delegate { _debugger?.uiUpdateTimer_Tick(null, EventArgs.Empty); });
+                        break;
                     }
-                    else
+
+                    // 4. Calculate TRUE Frame Time (Compute Time) BEFORE we go to sleep!
+                    FrameTime = _stopwatch.Elapsed.TotalMilliseconds - frameStartTime;
+
+                    // --- HIGH PRECISION THROTTLE ---
+                    while (_stopwatch.Elapsed.TotalMilliseconds < nextFrameTargetTime)
                     {
-                        // Only throttle the speed if we are actively running
-                        Thread.Sleep(8);
+                        if (nextFrameTargetTime - _stopwatch.Elapsed.TotalMilliseconds > 2.0)
+                        {
+                            Thread.Sleep(1);
+                        }
+                        else
+                        {
+                            Thread.SpinWait(10);
+                        }
+                    }
+
+                    // --- METRICS MATH ---
+                    double currentTime = _stopwatch.Elapsed.TotalMilliseconds;
+                    TotalFrameCount++;
+                    framesThisSecond++;
+
+                    if (currentTime - lastFpsUpdate >= 1000.0)
+                    {
+                        FramesPerSecond = framesThisSecond / ((currentTime - lastFpsUpdate) / 1000.0);
+                        framesThisSecond = 0;
+                        lastFpsUpdate = currentTime;
+
+                        BeginInvoke((System.Windows.Forms.MethodInvoker)delegate {
+                            this.Text = $"Parsons Master System - {_currentRomName} [FPS/FT: {FramesPerSecond:F0}/{FrameTime:F1}]";
+                        });
+                    }
+
+                    nextFrameTargetTime += TargetFrameTime;
+
+                    if (currentTime > nextFrameTargetTime + TargetFrameTime)
+                    {
+                        nextFrameTargetTime = currentTime + TargetFrameTime;
                     }
                 }
             });
@@ -102,8 +156,8 @@ namespace Desktop
             // 3. Jam it into the Sega Mapper
             _machine.LoadCartridge(rom);
 
-            // 4. Update the Window title so it looks professional
-            this.Text = $"Parsons Master System 2026 - {Path.GetFileNameWithoutExtension(filePath)}";
+            _currentRomName = Path.GetFileNameWithoutExtension(filePath);
+            this.Text = $"Parsons Master System - {_currentRomName}";
 
             // 5. Turn the power on!