osmWorkflow/.trellis/tasks/archive/2026-08/08-04-add-osm-turn-lane-arrows/research/lane-icons.md

lane-icons research

Source: https://github.com/openstreetmap/lane-icons, inspected 2026-08-04.

Provenance

• Owner: openstreetmap GitHub organization.
• Repository tree revision: db3cab321da93a757c2cf3cdb4f1f1db6b1a091c (master).
• License: LICENSE.md is CC0 1.0 Universal. Keep that text adjacent to any vendored source assets.

Relevant Contents

• docs/through.svg
• docs/left.svg
• docs/left-through.svg
• docs/slight_left.svg
• docs/slight_left-through.svg
• docs/sharp_left.svg
• docs/sharp_left-through.svg
• docs/reverse_left.svg
• docs/reverse_left-through.svg
• docs/reverse_left-left-slight_left-through.svg
• docs/left-slight_left-through.svg

Design Rules

DESIGN.md bases arrows on the MUTCD Standard Arrow. It specifies a shared shaft for compound arrows, smooth curves, aligned arrow bottoms, and reduced arrowhead scale as the number of directions grows. The upstream SVGs are single-color and stroke-free; our existing render layer supplies the project fill and outline treatment.

Adoption Decision

Vendor all listed arrow SVGs with provenance and CC0 license text. The production mapping is initially restricted to through, left, right, through;left, and through;right. Right-side variants are deterministic mirrors of upstream left-side assets. Every other vendored arrow remains explicitly untested and unavailable to the production mapper.