Refine editor UX and startup diagnostics

Engine/Source/Core/Application/ApplicationClock.cpp

@@ -3,9 +3,15 @@
 #include <algorithm>
 #include <cmath>
 #include <stdexcept>
+#include <string>
 
 namespace WaveApplication
 {
+	namespace
+	{
+		constexpr uint8 VariableWarmupSampleBudget = 3;
+	}
+
 	FApplicationClock::FApplicationClock(FApplicationTimingConfig InConfig)
 		: Config(std::move(InConfig))
 	{
@@ -51,19 +57,41 @@ namespace WaveApplication
 		}
 
 		FApplicationClockSample Sample;
+		bool bWarmupClamp = false;
 		Sample.TickSequence = TickSequence;
 		Sample.RealTimeSeconds = MonotonicSeconds;
 		Sample.bFirstTick = !PreviousSeconds.has_value();
 		Sample.RealDeltaSeconds = PreviousSeconds
 			? MonotonicSeconds - *PreviousSeconds
 			: 1.0 / 60.0;
-		Sample.GameDeltaSeconds = std::min(Sample.RealDeltaSeconds, Config.MaxDeltaSeconds);
-		Sample.bClamped = Sample.RealDeltaSeconds > Config.MaxDeltaSeconds;
 		if (Config.FixedDeltaSeconds)
 		{
 			Sample.GameDeltaSeconds = *Config.FixedDeltaSeconds;
 			Sample.bFixed = true;
 		}
+		else
+		{
+			Sample.GameDeltaSeconds = std::min(
+				Sample.RealDeltaSeconds,
+				Config.MaxDeltaSeconds);
+			Sample.bClamped = Sample.RealDeltaSeconds > Config.MaxDeltaSeconds;
+			if (!Sample.bFirstTick)
+			{
+				bWarmupClamp = Sample.bClamped
+					&& !bVariableWarmupComplete
+					&& VariableWarmupSampleCount < VariableWarmupSampleBudget;
+				if (!Sample.bClamped)
+				{
+					bVariableWarmupComplete = true;
+				}
+				else if (!bVariableWarmupComplete)
+				{
+					++VariableWarmupSampleCount;
+					bVariableWarmupComplete =
+						VariableWarmupSampleCount >= VariableWarmupSampleBudget;
+				}
+			}
+		}
 
 		PreviousSeconds = MonotonicSeconds;
 		++TickSequence;
@@ -73,8 +101,16 @@ namespace WaveApplication
 			Result.Diagnostics.push_back({
 				"application.clock.delta_clamped",
 				"clock.game_delta_seconds",
-				"Variable game delta was clamped to the configured maximum.",
-				EApplicationDiagnosticSeverity::Warning,
+				std::string(bWarmupClamp
+					? "Startup warmup variable game delta of "
+					: "Variable game delta of ")
+					+ std::to_string(Sample.RealDeltaSeconds)
+					+ " seconds was clamped to the configured maximum of "
+					+ std::to_string(Config.MaxDeltaSeconds)
+					+ " seconds.",
+				bWarmupClamp
+					? EApplicationDiagnosticSeverity::Info
+					: EApplicationDiagnosticSeverity::Warning,
 				false,
 			});
 		}
@@ -85,5 +121,7 @@ namespace WaveApplication
 	{
 		PreviousSeconds.reset();
 		TickSequence = 0;
+		VariableWarmupSampleCount = 0;
+		bVariableWarmupComplete = false;
 	}
 }

Engine/Source/Core/Application/ApplicationClock.h

@@ -36,5 +36,7 @@ namespace WaveApplication
 		FApplicationTimingConfig Config;
 		std::optional<double> PreviousSeconds;
 		uint64 TickSequence = 0;
+		uint8 VariableWarmupSampleCount = 0;
+		bool bVariableWarmupComplete = false;
 	};
 }

Engine/Source/UI/EditorApplication.cpp

@@ -25,6 +25,7 @@
 #include <iostream>
 #include <memory>
 #include <stdexcept>
+#include <string>
 #include <string_view>
 #include <system_error>
 #include <utility>
@@ -683,19 +684,52 @@ namespace
 		return "unknown";
 	}
 
-	void LogApplicationDiagnostics(const FApplicationStatusSnapshot& Status)
+	std::string FormatApplicationDiagnostic(
+		const FApplicationDiagnostic& Diagnostic)
 	{
-		for (const FApplicationDiagnostic& Diagnostic : Status.Diagnostics)
-		{
-			Log::Error(
-				"Application diagnostic [",
-				DiagnosticSeverityName(Diagnostic.Severity),
-				"] ",
-				Diagnostic.Code,
-				" at ",
-				Diagnostic.Path,
-				": ",
-				Diagnostic.Message);
+		std::string Message = "Application diagnostic [";
+		Message += DiagnosticSeverityName(Diagnostic.Severity);
+		Message += "] ";
+		Message += Diagnostic.Code;
+		Message += " at ";
+		Message += Diagnostic.Path;
+		Message += ": ";
+		Message += Diagnostic.Message;
+		return Message;
+	}
+
+	void LogApplicationDiagnostic(const FApplicationDiagnostic& Diagnostic)
+	{
+		const std::string Message = FormatApplicationDiagnostic(Diagnostic);
+		switch (Diagnostic.Severity)
+		{
+		case EApplicationDiagnosticSeverity::Info:
+			Log::Info(Message);
+			break;
+		case EApplicationDiagnosticSeverity::Warning:
+			Log::Warning(Message);
+			break;
+		case EApplicationDiagnosticSeverity::Error:
+		case EApplicationDiagnosticSeverity::Fatal:
+			// Log::Fatal throws; lifecycle diagnostics have already selected the
+			// safe shutdown or quarantine path and must only be reported here.
+			Log::Error(Message);
+			break;
+		}
+	}
+
+	void LogNewApplicationDiagnostics(
+		const FApplicationStatusSnapshot& Status,
+		size_t& LoggedDiagnosticCount)
+	{
+		if (LoggedDiagnosticCount > Status.Diagnostics.size())
+		{
+			LoggedDiagnosticCount = 0;
+		}
+		while (LoggedDiagnosticCount < Status.Diagnostics.size())
+		{
+			LogApplicationDiagnostic(Status.Diagnostics[LoggedDiagnosticCount]);
+			++LoggedDiagnosticCount;
 		}
 	}
 }
@@ -726,7 +760,10 @@ int RunEditorApplication()
 	Runner.RegisterService(AdapterService);
 
 	SET_THREAD_NAME("Main Thread");
-	if (Runner.Initialize(IdleCoordinator))
+	size_t LoggedDiagnosticCount = 0;
+	const bool bInitialized = Runner.Initialize(IdleCoordinator);
+	LogNewApplicationDiagnostics(Runner.QueryStatus(), LoggedDiagnosticCount);
+	if (bInitialized)
 	{
 		while (Runner.QueryStatus().State == EApplicationLifecycleState::Running)
 		{
@@ -742,13 +779,16 @@ int RunEditorApplication()
 				SCOPED_CPU_EVENT("Frame");
 				(void)Runner.Tick(GetMonotonicSeconds());
 			}
+			LogNewApplicationDiagnostics(
+				Runner.QueryStatus(),
+				LoggedDiagnosticCount);
 			GlobalContext.FrameIndex = Runner.QueryStatus().TickSequence;
 		}
 		Runner.Shutdown(IdleCoordinator);
 	}
 
 	const FApplicationStatusSnapshot& Status = Runner.QueryStatus();
-	LogApplicationDiagnostics(Status);
+	LogNewApplicationDiagnostics(Status, LoggedDiagnosticCount);
 	if (Status.State == EApplicationLifecycleState::Quarantined)
 	{
 		Log::Error(

Engine/Source/UI/EditorWidgets.cpp

@@ -775,6 +775,21 @@ void EditorWidgets::Icon(EEditorIcon EditorIcon, EEditorColor Color, float Size)
 		FEditorStyle::ColorU32(Color));
 }
 
+void EditorWidgets::IconAt(
+	ImDrawList* DrawList,
+	const ImVec2& Position,
+	EEditorIcon EditorIcon,
+	EEditorColor Color,
+	float Size)
+{
+	DrawEditorIcon(
+		DrawList,
+		EditorIcon,
+		Position,
+		FEditorStyle::Scale(Size),
+		FEditorStyle::ColorU32(Color));
+}
+
 bool EditorWidgets::Button(
 	const char* Id,
 	EEditorIcon ButtonIcon,

Engine/Source/UI/EditorWidgets.h

@@ -92,6 +92,12 @@ namespace EditorWidgets
 		EEditorIcon Icon,
 		EEditorColor Color = EEditorColor::TextMuted,
 		float Size = 16.0f);
+	void IconAt(
+		ImDrawList* DrawList,
+		const ImVec2& Position,
+		EEditorIcon Icon,
+		EEditorColor Color = EEditorColor::TextMuted,
+		float Size = 16.0f);
 
 	// Vector-icon buttons keep the same geometry for hover, pressed, disabled
 	// and keyboard-focus states. Id is never rendered and must be stable.