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merging your prs

Tom MacWright tmcw

merging your prs
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tmcw /
Created December 28, 2022 17:00
PMTiles to SVG

Request a single tile from PMTiles, use the vector-tiles module to read it, the d3-geo tools to turn it into a string. d3-geo is probably unnecessary.

This approach feels limited:

Requires restitching tiles if more than one. Limited attributes. Any tile-based solution is going to make compromises in favor of responsiveness and lightweight data. What this wants is completeness and non-sliced data.

View webfinger.ts
import { Context } from "";
const DOMAIN = "";
const USERS = new Map([
subject: `acct:photos@${DOMAIN}`,
aliases: [],
View progress.tsx
import { Portal } from "@radix-ui/react-portal";
import clsx from "clsx";
import { useAtom } from "jotai";
import { atomWithMachine } from "jotai/xstate";
import { useRouter } from "next/router";
import { useEffect } from "react";
import { assign, createMachine } from "xstate";
import clamp from "lodash/clamp";
View use_map_keybindings.ts
export function useMapKeybindings() {
const rep = usePersistence();
const historyControl = rep.useHistoryControl();
const transact = rep.useTransact();
"Command+z, Ctrl+z",
(e) => {
View persistence.ts
import { createContext, useContext } from "react";
import type { IPersistence } from "app/lib/persistence/ipersistence";
const notInContext = {} as IPersistence;
export const PersistenceContext = createContext<IPersistence>(notInContext);
export function usePersistence() {
return useContext(PersistenceContext);
View ipersistence.ts
export interface MomentInput {
note?: string;
putFeatures: IWrappedFeatureInput[];
deleteFeatures: IWrappedFeature["id"][];
putFolders: IFolderInput[];
deleteFolders: IFolder["id"][];
export interface IPersistence {
useHistoryControl(): (direction: "undo" | "redo") => Promise<void>;
View example.js
// User ID
"id": 1,
"type": "Feature",
"properties": {
// System ID
"@id": "d13b47c0-23fb-11ed-a50b-8b6722c6e6fe"
"geometry": {
"type": "Point",
View example.js
import { wktToGeoJSON, geoJSONToWkt } from "betterknown";
import proj4 from "proj4";
// Converting & reprojecting an EWKT string
wktToGeoJSON(`SRID=3857;POINT(-400004.3 60000.1)`, {
proj: proj4,
// Converting GeoJSON to WKT

A faster format in Placemark

Placemark uses GeoJSON, and JSON, everywhere. In the database, features are GeoJSON. When we're sending features into Mapbox GL, it's GeoJSON getting sent with postMessage.

GeoJSON, of course, has its issues:

  • Sending GeoJSON features across to the WebWorker that cuts tiles for Mapbox GL JS is a major bottleneck for the core editing experience.
  • GeoJSON in resident memory is bigger than it needs to be. GeoJSON's coordinate arrays, especially, are an issue - flat arrays would be much more compact.
  • Mapbox GL JS itself has to cut GeoJSON into tiles, which requires some transformation - it creates another flat representation of geometry coordinates.
tmcw / states-income-data.csv
Created July 29, 2022 19:18
Example files to join
View states-income-data.csv
State HouseholdIncome
Maryland 84805
New Jersey 82545
Hawaii 81275
Massachusetts 81215
Connecticut 78444
Alaska 77640
New Hampshire 76768
California 75235
Virginia 74222