Performance Profiling and Analysis Guide

This document describes how to configure and use performance profiling and analysis tools when working with the Rendering Engine.

It explains:

• Runtime configuration parameters
• FPS and frame pacing controls
• Logging levels
• Performance measurement workflow
• Asset loading analysis
• Best practices for production builds

1. Runtime Configuration

Performance-related settings are configured via the application configuration file:

{
  "appName": "@PROJECT_NAME@",
  "isFullScreen": false,
  "screenWidth": 1920,
  "screenHeight": 1024,
 
  "text": {
    "scripts": ["Latin"],
    "fontSizePreload": [10]
  },
 
  "logLevel": "Debug",
 
  "useSmoothedFPS": false,
  "targetFPS": 60,
  "showStatsOverlay": true
}

1.1 logLevel

Controls verbosity of engine logging.

Available values:

"Error"
"Warning"
"Info"
"Debug"

Recommended usage

Build Type	logLevel
Development	Debug
Testing	Info
Production	Warning or Error

Debug level provides detailed timing and memory metrics.

1.2 useSmoothedFPS

Controls how FPS values are reported by the engine.

When enabled:

• FPS values are exponentially smoothed.
• Displayed statistics appear more stable.
• Useful for user-facing builds or demonstrations.

When disabled:

• Raw, unsmoothed FPS values are used.
• Preferred for precise performance profiling and regression tracking.

Note: This option affects only statistical reporting. It does not change frame pacing or frame limiting behavior.

Recommended usage

• Disable (false) when profiling performance bottlenecks
• Enable (true) when testing user experience stability

1.3 targetFPS

Specifies the desired frame rate cap.

Examples:

targetFPS	Behavior
0	Uncapped
60	Cap at 60 FPS
120	Cap at 120 FPS

1.4 Text Preloading Configuration

"text": {
  "scripts": ["Latin"],
  "fontSizePreload": [10],
  "showStatsOverlay": true
}

Controls font atlas preloading at startup.

Limiting scripts and sizes:

• Reduces startup time
• Reduces GPU memory usage
• Reduces RAM usage

For production builds, preload only required scripts and sizes.

2. Using the Stats Overlay

The engine supports a runtime statistics overlay. Enable it via:

"showStatsOverlay": true

When enabled, it displays:

• FPS
• Frame time (ms)
• Update time
• Render time
• RAM and GPU memory usage (if available)

3. Analyzing Logs

Engine logs provide detailed performance data.

Example:

Texture uploaded to GPU: test_cube_color (6422528 bytes, 16.603701 ms)
Loaded 7 textures from folder in 336.087799 ms.
Scene 'StartLevel' loaded in 10.191300 ms
CoreApplication initialized in 985 ms.

Log entries provide timing and memory information for:

• Application startup
• Scene loading
• Texture uploads
• RAM usage
• GPU usage
• Font atlas generation

4. Asset Loading Performance

All assets inside the Content folder are processed during application initialization.

This includes:

• Textures
• Models
• Fonts
• Shaders

Important

In production builds, it is recommended to include only assets that are required by the application. Unused assets:

• Increase startup time
• Increase RAM usage
• Increase GPU memory usage
• Slow down iteration

5. Measuring Startup Cost

Look for these entries:

CoreApplication initialized in XXX ms
SceneManager initialized in XXX ms
Loaded N textures in XXX ms
Font atlas preloading completed in XXX ms

These metrics allow you to:

• Track regression between commits
• Compare builds
• Measure impact of new systems

6. Production Readiness Checklist

Before shipping:

• logLevel set to Warning or Error
• useSmoothedFPS enabled
• targetFPS set appropriately (60 recommended)
• Unused assets removed
• Startup time measured
• Scene load time measured
• GPU memory usage verified

7. GPU Profiling with RenderDoc

For deep GPU-level inspection, the Rendering Engine can be analyzed using RenderDoc, an open-source graphics debugger:

RenderDoc

RenderDoc can be used to:

• Capture a single rendered frame
• Inspect draw calls
• Analyze bound pipelines and descriptor sets
• View vertex buffers and index buffers
• Inspect textures and framebuffer attachments
• Step through the graphics pipeline stages
• Examine shader inputs/outputs
• Detect overdraw and redundant state changes