Collision Detection

Gondwana’s collision system is scene-oriented and AABB-based.

Each Scene owns collision groups, and each SceneLayer exposes a collider registry and a collision resolver.

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Resolution model

The current resolver is intentionally simple and practical:

• broad-phase query against the registry
• overlap detection in world pixel space
• trigger overlaps reported without push-out
• solid-vs-solid collisions resolved by minimum-axis push-out
• blocked velocity components are canceled so motion can slide on the free axis

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Why this fits the engine

Gondwana is a 2.5D rendering engine with strong tile/sprite assumptions. AABB collision is a good match for that style of game logic and keeps the runtime behavior understandable.

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Important detail

Collision resolution runs after movement in the engine cycle. That means movers advance first, then get corrected if they overlap.

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Mental model

Movement produces a proposed position.

Collision resolution decides whether that position is legal.

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Where to read next

• Gondwana/Collisions/CollisionResolver.cs
• Gondwana/Collisions/
• Gondwana/Scenes/SceneLayer.cs