Struct MeshRow 

pub(super) struct MeshRow<'a> {

    pub express_id: u32,
    pub ifc_type: &'a str,
    pub v_start: u32,
    pub vert_count: u32,
    pub i_start: u32,
    pub index_count: u32,
    pub color: [f32; 4],
    pub origin: [f64; 3],
    pub geometry_class: u8,
    pub geometry_item_id: Option<u32>,
    pub material_id: Option<u32>,
    pub finish: [f32; 2],
    pub rotation: [f32; 9],
}

One mesh’s row across the three tables, in the order mesh_schema() lists.

A struct, not the 11-element tuple this was. That tuple was POSITIONAL and several slots share a type – the four u32 offsets/counts, and the two Option<u32> source ids. Measured BEFORE this branch grew its tests: swapping the two ids compiled and left 202/202 green, writing every representation-item id into the material column and back.

It is caught now – mesh_table_carries_both_source_ids_on_the_right_columns fails on that swap. Named fields make it unreachable at the construction site as well, which is belt and braces, not a reason to drop the test: the RecordBatch arrays are still positional against the schema.

Fields

express_id: u32

ifc_type: &'a str

v_start: u32

vert_count: u32

i_start: u32

index_count: u32

color: [f32; 4]

origin: [f64; 3]

In the SAME Y-up frame as the emitted positions. The swap is linear, so swap(origin + position) = swap(origin) + swap(position); see services::axis for the one definition.

geometry_class: u8

geometry_item_id: Option<u32>

material_id: Option<u32>

finish: [f32; 2]

[metallic, roughness], NaN where unauthored (#5984).

rotation: [f32; 9]

Row-major 3x3, Y-up, placing the SHARED block this row points at: world = origin + R * p. Identity for a row that owns its geometry.

Implementations

impl<'a> MeshRow<'a>

pub fn new(mesh: &'a MeshData, placement: RowPlacement) -> Self

Build one row from an occurrence and the placement of the shape block it draws.

Here rather than at the call site so the field order is stated once, next to the schema whose column order it feeds. On every unshared row, which is every row of a -parquet-v8 payload, the block is mesh’s own.