Function build_vector_batch 

pub fn build_vector_batch(
    device: &Device,
    mesh: &VectorMeshData,
    camera_origin: DVec3,
) -> Option<VectorBatchEntry>

Build a vector batch entry from engine-tessellated mesh data.

Returns None if the mesh has no indices (nothing to draw).

Arguments

• device – WGPU device for buffer allocation.
• mesh – Tessellated vector geometry from the engine.
• camera_origin – Subtracted from positions for camera-relative f32.

Panics (debug only)

Debug-asserts that positions.len() == colors.len(). A mismatch would cause the zip to silently truncate vertices while indices still reference the original (larger) range, producing GPU-side out-of-bounds reads.