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Documentation/performance-profiling-with-unreal-insights.md

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+This guide will help you find performance problems in your C++ code using [Unreal Insights](https://docs.unrealengine.com/5.0/en-US/unreal-insights-in-unreal-engine/), included with Unreal Engine.
 
+Unreal Insights can display the scope of timing events as well as activity across threads. There is minimal impact to app execution, and you can set up your own custom events. It provides more functionality than an exclusive [CPU sampling-based profiler](https://learn.microsoft.com/en-us/visualstudio/profiling/understanding-performance-collection-methods-perf-profiler?view=vs-2022), although both tools can complement each other.
+
+# Set up a repeatable test
+
+We need an area of code to execute repeatedly, with as many variables locked down as possible. 
+
+In this example, we will use our Cesium performance tests.
+
+### Set up Unreal
+1) Open Unreal Editor (UnrealEditor.exe)
+2) Create a blank map (project doesn't matter. Choose an existing one or create a new one)
+3) Go to Edit->Plugins
+4) Search for "Functional Testing plugin". Check it to enable it
+![smaller](https://github.com/CesiumGS/cesium-unreal/assets/130494071/5a3bc9de-cdaf-4d9d-842d-104719426663)
+5) Save all
+6) Set this map as the 'Editor Startup Map' so it loads when starting from Visual Studio
+![smaller 2](https://github.com/CesiumGS/cesium-unreal/assets/130494071/8ba5c6c2-8c97-4048-afe2-db74770d85cc)
+
+
+### Build Release Code
+
+We need to make sure all our C++ code is building in release mode.
+
+> This assumes that you have already built your code successfully and are familiar with the concepts from our [developer setup guide](https://github.com/CesiumGS/cesium-unreal/blob/ue5-main/Documentation/developer-setup-windows.md). Although you could profile a debug build, it is typically more useful to build in release, since this is how a game is usually packaged.
+
+1) If building the cesium-native library, make sure you are using a Release configuration
+2) Open your Unreal project's Visual Studio solution (.sln). This example uses the solution generated from [cesium-unreal-samples](https://github.com/CesiumGS/cesium-unreal-samples)
+3) Choose "Development Editor"
+
+![smaller 3](https://github.com/CesiumGS/cesium-unreal/assets/130494071/0e70065f-c717-466b-a92b-cab1dcfdd29b)
+
+4) From the menu, choose Build -> Build Solution
+
+
+# Setup Unreal Editor + Unreal Insights for capture
+
+TODO
+
+# Run the timing capture session
+
+TODO
+
+
+# Interpret the report
+
+TODO
+
+### Start at the timeline
+
+TODO
+
+### Examine low use areas
+
+TODO
+
+# Draw conclusions
+
+TODO