RIVERS FONT — DATA AND THIRD-PARTY ATTRIBUTION

River geometry: HydroRIVERS v1.0, https://www.hydrosheds.org/products/hydrorivers
Lehner, B., and Grill, G. (2013): Global river hydrography and network routing: baseline data and new approaches to study the world's large river systems. Hydrological Processes, 27(15), 2171–2186. https://doi.org/10.1002/hyp.9740

This product Rivers Font incorporates data from the HydroSHEDS version 1 database which is © World Wildlife Fund, Inc. (2006-2022) and has been used herein under license. WWF has not evaluated the data as altered and incorporated within Rivers Font, and therefore gives no warranty regarding its accuracy, completeness, currency or suitability for any particular purpose. Portions of the HydroSHEDS v1 database incorporate data which are the intellectual property rights of © USGS (2006-2008), NASA (2000-2005), ESRI (1992-1998), CIAT (2004-2006), UNEP-WCMC (1993), WWF (2004), Commonwealth of Australia (2007), and Her Royal Majesty and the British Crown and are used under license. The HydroSHEDS v1 database and more information are available at https://www.hydrosheds.org.

Lehner, B., Verdin, K., Jarvis, A. (2008): New global hydrography derived from spaceborne elevation data. Eos, Transactions, AGU, 89(10): 93-94.
License: https://data.hydrosheds.org/file/technical-documentation/HydroSHEDS_TechDoc_v1_4.pdf

AMAZON (WATER EDITION) — SURFACE WATER
Amazon glyphs are traced from the JRC Global Surface Water dataset, v1.4 (1984–2021), occurrence layer, 30 m.
Pekel, J.-F., Cottam, A., Gorelick, N., Belward, A. S. (2016): High-resolution mapping of global surface water and its long-term changes. Nature 540, 418–422. https://doi.org/10.1038/nature20584
Source: EC JRC / Google, https://global-surface-water.appspot.com — licensed CC BY 4.0. Altered: thresholded at 50% occurrence, limited to the Amazon basin, traced, rotated, uniformly scaled, and (for confluence glyphs) 2–3 real pieces joined.

METHOD
All glyph paths originate in HydroRIVERS source geometry: individual reaches, connected downstream reaches, or geographic network crops. Paths are simplified at 0.1% of their span to remove redundant vertices, then rotated and uniformly scaled. No hand-drawn or constructed letter is substituted. Letter assignments are automatic, experimental, and unreviewed. They are not a certified legible alphabet. TTF/WOFF2 font outlines buffer the source linework to give it visible stroke width; they use the default candidate mapping.

Hershey matching templates (used only for scoring, not glyph artwork):
The Hershey Fonts were originally created by Dr. A. V. Hershey while working at the U.S. National Bureau of Standards. The format of the Font data in this distribution was originally created by James Hurt, Cognition, Inc., 900 Technology Park Drive, Billerica, MA 01821 (mit-eddie!ci-dandelion!hurt).
Converted JSON source: https://github.com/techninja/hersheytextjs
Conversion code copyright (c) 2014 James T, MIT License. Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the Software), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to inclusion of this copyright and permission notice. THE SOFTWARE IS PROVIDED AS IS, WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

UI FONTS
DM Sans, DM Mono, Instrument Serif. Distributed under the SIL Open Font License 1.1. Full notices are in fonts/ui/*-OFL.txt. These interface fonts are never used as substitute river glyphs.

REFERENCE ONLY
Igaratype / Amazônia: https://igaratipo.visiteamazonia.com.br/en/
FutureBrand and João Generoso. Used for independent visual comparison and interaction research. No Igaratype glyph artwork, font, or code is included. Rivers Font is independent and is not endorsed by the referenced organizations.

River and state names on the letter cards: © OpenStreetMap contributors, available under the Open Database License (ODbL), https://www.openstreetmap.org/copyright. Looked up via the Overpass API and Nominatim.