# 0002. Half-scale voxel grid

- **Status:** Accepted
- **Date:** 2026-06-27

## Context

The world is entirely built from voxels. The physical edge length we choose for a voxel directly impacts nearly every system: collision resolution, mesh chunking, level-of-detail thresholds, network bandwidth, and in-memory data layout all scale directly with voxel density. While a finer grid allows for much more expressive terrain and building, it comes at a steep cost in total voxel count per unit volume.

Compared to a conventional coarse voxel grid with a 1-meter edge, halving the edge to 0.5 meters doubles the linear resolution but multiplies the voxel count per unit volume by roughly 8x.

## Decision

We are setting the voxel edge to exactly **0.5 meters**. Inside the engine, the base world unit is the block itself (**1 unit = 1 block**). We count in blocks rather than meters. Because of this, a standard player occupies **3 units tall by 2 units wide** (3 blocks by 2 blocks).

## Consequences

- The density is roughly 8x that of a 1-meter grid world per unit volume. We absolutely must design chunk dimensions and voxel data layouts with this multiplier in mind; a data layout that feels comfortable on a coarse grid might be completely unviable here.
- Collision, meshing, LOD selection, and network bandwidth budgets all inherit this 8x factor and have to be designed against it from day one.
- The motivating benefit is that we can support much finer terrain and construction detail.
- This is a load-bearing choice that will be incredibly expensive to revisit later, mainly because persisted worlds and save formats fundamentally encode the block scale.