Architecture: locate implementation and trace defects

Use this section when reading engine implementation, investigating a defect or preparing a C++ extension. For a first game project, start with entities, levels and prefabs.

Choose a task

• Subsystem map: Entity, Resource, servers, core and startup
• Objects, signals, deferred calls and lifetime
• Class inheritance and registered-type lookup
• Variant and typed value exchange
• C++ containers, strings and core types
• C++ utility methods and macros
• Rendering internals
• 2D coordinate transforms
• Engine unit tests

Trace a defect

1. Find the public type and method in the C# reference. Check argument types, resource ownership and call timing.
2. For Entity behavior, start in Source/scene/; for a server operation, use the relevant subsystem in Source/servers/. A class and a server can represent the same game object at different levels.
3. For type registration, Variant and lifetime, start in Source/core/. Look in Source/platform/ for platform differences and also in Source/drivers/ and Source/modules/ for backend implementations.
4. For startup order, physics stepping and frame synchronization, open Source/main/main.cpp. A method name alone does not establish thread ordering.

Reproduce the issue in a separate minimal project first. Running a C# example on the installed runtime does not validate a modified C++ build or another platform. This page routes you through the current code; consult the corresponding guides for build settings and tools.