Comprehensive Technical Documentation Generation

CRITICAL REQUIREMENTS - FORENSIC ACCURACY MANDATE

Zero-Assumption Policy

Documentation Mission & Scope

  1. Create comprehensive technical documentation for godot-cpp’s internal mechanisms, focusing exclusively on:
    • Internal implementation details rarely documented elsewhere
    • Complex type system and marshalling mechanisms
    • ClassDB internals and template metaprogramming
    • Memory management boundaries and ownership rules
    • Binary communication between GDExtension libraries and Godot Engine
    • All error conditions (internal and user-facing)
  2. Maintain a very detailed progress tracker to track progress as well as being able to refer to when determining if the task is complete

Target Audience Profile

Documentation Depth Requirements

  1. Internal Mechanisms Priority
    • Document ALL internal utilities, structures, and mechanisms including:
      • Private/protected class members and their purposes
      • Internal-only macros and their expansion patterns
      • Hidden utility functions and their use cases
      • Template metaprogramming techniques
      • Undocumented helper structures
      • Implementation-detail namespaces
  2. Technical Focus Only
    • EXCLUDE high-level topics covered in official documentation:
      • Getting started guides
      • Basic Godot concepts
      • Historical evolution (GDNative to GDExtension)
      • General engine overview
    • INCLUDE technical implementation details:
      • Binary interface mechanics
      • Function pointer resolution
      • Type erasure implementation
      • Memory layout specifications
      • ABI compatibility mechanisms
  3. Platform-Specific Technical Content
    • Document platform-specific details when they contain:
      • Technical workarounds for platform limitations
      • Platform-exclusive build requirements
      • Edge cases unique to specific platforms
      • Conditional compilation patterns
      • Platform-specific memory alignment requirements
      • Toolchain-specific optimizations or issues
  4. Code Examples Structure
    • Inline Snippets: Focused code demonstrating specific concepts
    • Complete Projects (3 total):
      1. Simple: Basic extension demonstrating core concepts
      2. Advanced: Complex patterns and optimization techniques
      3. Integration: Third-party library integration patterns
  5. Comprehensive Error Documentation
    • Document EVERY error condition:
      • Internal assertions and their triggers
      • User-facing error messages and causes
      • Silent failures and their detection
      • Memory corruption scenarios
      • Thread safety violations
      • ABI mismatch conditions
      • Include error macros: ERR_FAIL_, CRASH_, DEV_ASSERT, etc.
  6. Godot Engine Interface Documentation
    • Document ONLY engine aspects required for understanding godot-cpp:
      • GDExtension interface contract
      • Object ownership boundaries
      • Memory allocation responsibilities
      • Call conventions and marshalling
      • Thread safety guarantees
      • Version compatibility mechanisms

Required Documentation Sections with Detail Level

Part I: Foundation & Architecture

  1. Core Architecture (15-20 pages equivalent)
    • Binary communication mechanisms
    • Function pointer tables and resolution
    • Interface versioning and negotiation
    • Memory barriers between binaries
    • ABI stability guarantees
  2. Memory Model (10-15 pages)
    • Custom allocator implementation details
    • Alignment requirements and calculations
    • Reference counting implementation
    • Object lifecycle state machines
    • Memory ownership transfer rules
  3. Initialization Pipeline (8-10 pages)
    • Complete startup sequence with code references
    • Interface function loading order
    • Failure modes and recovery
    • Platform-specific initialization differences

Part II: Type System Internals

  1. Variant Implementation (20-25 pages)
    • 24-byte opaque storage layout diagrams
    • Type discrimination mechanisms
    • Conversion matrices for all 40+ types
    • Copy-on-write optimizations
    • String encoding conversions
    • Performance characteristics
  2. ClassDB Internals (25-30 pages)
    • ClassInfo structure detailed breakdown
    • MethodBind creation and storage
    • Template metaprogramming for method binding
    • Virtual method table construction
    • Property getter/setter mechanisms
    • Signal connection internals
    • GDCLASS macro expansion analysis
  3. Template Specializations (15-20 pages)
    • Type traits for object classification
    • SFINAE patterns for method resolution
    • Template-based marshalling code
    • Compile-time type safety mechanisms
    • Cross-binary type identification

Part III: Code Generation System

  1. Binding Generator Deep Dive (20-25 pages)
    • extension_api.json complete schema documentation
    • Template generation patterns with examples
    • Special case handling (operators, constructors)
    • Error handling in generated code
    • Performance optimizations in generation
  2. Generated Code Patterns (10-15 pages)
    • Method wrapper generation
    • Argument marshalling patterns
    • Return value handling
    • Default parameter implementation
    • Virtual method trampolines

Part IV: Build System Internals

  1. Build System Architecture (15-20 pages)
    • SCons configuration deep dive
    • Platform detection mechanisms
    • Compiler flag derivation logic
    • Link-time optimization settings
    • Dynamic source generation timing
  2. Platform-Specific Implementation (10-15 pages)
    • Windows: MSVC vs MinGW differences, DLL handling
    • Linux: Symbol visibility, RPATH handling
    • macOS/iOS: Framework generation, universal binaries
    • Android: NDK integration, JNI boundaries
    • Web: Emscripten specifics, WASM limitations

Part V: Advanced Implementation Patterns

  1. Complex Patterns (15-20 pages)
    • Thread-safe singleton implementation
    • Custom server creation
    • Performance-critical code patterns
    • Memory pool implementations
    • Lock-free data structures
  2. Error Handling & Debugging (10-15 pages)
    • Error propagation across binary boundaries
    • Stack trace preservation
    • Debug symbol management
    • Memory leak detection patterns
    • Thread sanitizer compatibility

Documentation Format Requirements

Markdown Requirements

Special Focus Areas

ClassDB Functionality Deep Dive

Document the complete ClassDB pipeline including:

Template Specialization & Type Traits

Document the template-based type system including:

Research & Validation Requirements

Primary Source Analysis (MANDATORY)

Must examine and document from:

Code Verification Process

For each documented feature:

  1. Locate primary implementation
  2. Trace complete execution path
  3. Identify all error conditions
  4. Find platform-specific variations
  5. Verify with test code if available
  6. Document actual vs expected behavior

Quality Metrics

Documentation must achieve:

Deliverable Requirements

Begin with:

  1. Detailed outline of each document with section headers and estimated content
  2. Critical code paths identified for deep analysis
  3. Complex systems requiring extensive investigation
  4. Questions about any ambiguous technical requirements

After approval:

Priority Order

  1. Highest Priority: ClassDB internals, Type system, Template specializations
  2. High Priority: Memory model, Initialization, Error handling
  3. Medium Priority: Code generation, Build system
  4. Lower Priority: Complete example projects (after inline examples)

This documentation will serve as the definitive technical reference for godot-cpp internals, providing the deep technical understanding required for advanced native extension development.

Quality Assurance

Verification Requirements

Completeness Checklist

Execution Strategy

Initial Setup

Batching Approach

Progress Tracking

Critical Notes