uv_rasterizer

UV-space scan-line triangle rasteriser for the lightmap bakers. Walks every triangle of an entity's mesh, projects it into UV pixel space, and for each covered texel writes the barycentric-interpolated world-space position and normal. Output is two flat vec4-strided float arrays ready for compute upload.

Exports

• Rast.rasteriseEntity(entityId: string, resolution: number?) -> RasterizeResult — rasterise one entity into per-texel position + normal buffers.

Types:

• FloatArray = { number }
• RasterizeResult = { positions: FloatArray, normals: FloatArray, texelCount: number, validCount: number }

Usage

local Rast = require("@builtin::systems.globalIllumination.uv_rasterizer")

local rast = Rast.rasteriseEntity(entityId, 64)
-- rast.positions: buffer, 64*64 texels x 4 f32 — (x, y, z, valid) per texel
-- rast.normals:   buffer, 64*64 texels x 4 f32 — (nx, ny, nz, pad) per texel

Notes

• Texels with no triangle coverage have positions[i*4+4] == 0. Bakers honour this w flag to skip empty texels; the lightmap shader uses it as a bilinear-filter weight to mask seams.
• Triangle coverage is determined via the standard edge-function test with a 1e-6 epsilon to keep adjacent triangles from leaving cracks along shared edges.
• Default resolution is 64 when the caller passes nil or a value less than 1.
• Output is in world space — vertex positions are transformed by the entity's world matrix (Baking.entityWorldMatrix) before being written; normals get the 3x3 portion of the same matrix.