TerraDraw adapter for MapGL JS API
TerraDraw adapter for MapGL JS API or just a simple drawing tool.
Install library
``bash`
npm install @2gis/mapgl-terra-draw
Use ui-helper createTerraDrawWithUI and not forget to plug css:
`ts
import { load } from '@2gis/mapgl';
import { createTerraDrawWithUI } from '@2gis/mapgl-terra-draw';
import '@2gis/mapgl-terra-draw/dist/mapgl-terra-draw.css';
load().then((mapgl) => {
const map = new mapgl.Map('map', {
center: [55.31878, 25.23584],
zoom: 13,
key: 'Your MapGL JS API key',
enableTrackResize: true,
});
map.on('styleload', () => {
createTerraDrawWithUI({
map,
mapgl: mapgl as any,
controls: ['color', 'select', 'point', 'polygon', 'circle', 'download', 'clear'],
});
});
});
`
Or directly in HTML via unpkg CDN
`html`
If advanced cases (use your custom drawing mode, customize a very flexible TerraDraw selection behaviour, design a fancy UI, e.g.) you can use TerraDrawMapGlAdapter class directly.
This gives you much more flexibility, but puts a some bunch of work on your side. Here is a simple example:
`ts
import { load } from '@2gis/mapgl';
import {
TerraDraw,
TerraDrawPointMode,
TerraDrawPolygonMode,
TerraDrawSelectMode,
} from 'terra-draw';
import { TerraDrawMapGlAdapter } from '@2gis/mapgl-terra-draw';
load().then((mapgl) => {
const map = new mapgl.Map('map', {
center: [55.31878, 25.23584],
zoom: 13,
key: 'Your MapGL JS API key',
enableTrackResize: true,
});
map.on('styleload', () => {
const draw = new TerraDraw({
adapter: new TerraDrawMapGlAdapter({
map,
mapgl,
coordinatePrecision: 9,
}),
modes: [
new TerraDrawSelectMode(),
new TerraDrawPointMode(),
new TerraDrawPolygonMode(),
],
});
const buttons = document.createElement('div');
buttons.style.display = 'flex';
buttons.style.flexDirection = 'column';
buttons.style.gap = '8px';
new mapgl.Control(map, buttons, { position: 'centerLeft' });
const selectButton = document.createElement('button');
selectButton.innerText = 'select';
selectButton.addEventListener('click', () => {
draw.setMode('select');
});
buttons.appendChild(selectButton);
const pointButton = document.createElement('button');
pointButton.innerText = 'point';
pointButton.addEventListener('click', () => {
draw.setMode('point');
});
buttons.appendChild(pointButton);
const polygonButton = document.createElement('button');
polygonButton.innerText = 'polygon';
polygonButton.addEventListener('click', () => {
draw.setMode('polygon');
});
buttons.appendChild(polygonButton);
const clearButton = document.createElement('button');
clearButton.innerText = 'clear';
clearButton.addEventListener('click', () => {
draw.clear();
});
buttons.appendChild(clearButton);
draw.start();
});
});
`
To get drawing data with styling use this code snippet:
`js
const adapter = new TerraDrawMapGlAdapter({
...
});
const { draw } = createTerraDrawWithUI({
adapter,
...
});
const features = draw.getSnapshot();
const { icons, layers } = adapter.addStyling(features);
const featureCollection = {
type: 'FeatureCollection',
icons,
layers,
features,
};
`
Here we obtain a standart GeoJSON FeatureCollection and put icons and layers props in the root (which is permitted by GeoJSON specification).
To display this data, you should add icons and layers to your MapGL map, and add GeoJSON via GeoJsonSource
`js`
for (const icon in featureCollection.icons) {
map.addIcon(icon, { url: featureCollection.icons[icon] });
}
for (const layer of featureCollection.layers) {
map.addLayer(layer);
}
const source = new mapgl.GeoJsonSource(map, {
data: featureCollection,
attributes: {
name: 'terra-draw-output',
},
});
You can use demo on codepen for reference.
If you want just geojson shapes of drawed feature use a .getSnapshot() method of a TerraDraw.
`ts
const { draw } = createTerraDrawWithUI({
...
});
...
draw.getSnapshot();
`
UI relies on Material Icons font to display icons. So you should include following link to your HTML head.
`html`
`
npm run build
npm publish --access=public
MIT