Coordinate Spaces

Gondwana uses several coordinate spaces on purpose, and understanding them early will save you a lot of confusion.

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Coordinate Space types

1. Grid space

Grid space is tile-relative. A position like (4, 7) means “column 4, row 7” on a given SceneLayer.

This is useful for:

• tile addressing
• map logic
• spawn placement
• coordinate-system-aware movement

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2. World pixel space

World space is Gondwana’s primary simulation space.

Most core engine logic happens here:

• camera position
• dirty rectangles
• sprite placement
• collision bounds
• layer origins
• view transforms

This is the engine’s real “source of truth.”

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3. Screen space

Screen space is render-surface space. These are the pixel coordinates on the destination surface after camera, parallax, viewport placement, and zoom have been applied.

This is where:

• the backbuffer is actually drawn
• dirty presentation regions are tracked
• view overlays live

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4. Layer-local projection space

Each SceneLayer has a coordinate system implementation that converts grid positions to world pixels. Orthogonal, isometric, and hex variants are handled at this layer.

That means grid-to-world math is layer-specific, not global.

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Key insight

Gameplay logic should usually think in world or grid space. Rendering code is where world becomes screen.

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Mental model

Grid -> World -> Screen

That pipeline is everywhere in Gondwana.

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Where to read next

• Gondwana/Scenes/SceneLayer.cs
• Gondwana/Rendering/Views/View.cs
• coordinate classes under Gondwana/Drawing/Coordinates/