Display a graticule on a Map.

Color
100% © U.S. Geological Survey

The Map can display a fully configurable graticule.

index.js
import colormap from 'colormap';
import { Color } from 'three';
import { MapControls } from 'three/examples/jsm/controls/MapControls.js';
import XYZ from 'ol/source/XYZ.js';

import Extent from '@giro3d/giro3d/core/geographic/Extent.js';
import Instance from '@giro3d/giro3d/core/Instance.js';
import ElevationLayer from '@giro3d/giro3d/core/layer/ElevationLayer.js';
import TiledImageSource from '@giro3d/giro3d/sources/TiledImageSource.js';
import Map from '@giro3d/giro3d/entities/Map.js';
import Inspector from '@giro3d/giro3d/gui/Inspector.js';
import Interpretation from '@giro3d/giro3d/core/layer/Interpretation.js';
import GeoTIFFFormat from '@giro3d/giro3d/formats/GeoTIFFFormat.js';
import ColorMap, { ColorMapMode } from '@giro3d/giro3d/core/layer/ColorMap.js';



const x = -13602000;
const y = 5812000;
const halfWidth = 25000;

// Defines geographic extent: CRS, min/max X, min/max Y
const extent = new Extent('EPSG:3857', x - halfWidth, x + halfWidth, y - halfWidth, y + halfWidth);

// `viewerDiv` will contain Giro3D' rendering area (the canvas element)
const viewerDiv = document.getElementById('viewerDiv');

// Creates a Giro3D instance
const instance = new Instance(viewerDiv, {
    crs: extent.crs(),
    renderer: {
        clearColor: 0x0a3b59,
    },
});

// Creates a map that will contain the layer
const map = new Map('planar', {
    extent,
    hillshading: true,
    discardNoData: true,
    doubleSided: true,
    backgroundColor: 'white',
    graticule: {
        enabled: true,
        color: new Color('white'),
        xStep: 500,
        yStep: 500,
        xOffset: 0,
        yOffset: 0,
        opacity: 1,
        thickness: 20,
    },
});

instance.add(map);

const source = new TiledImageSource({
    source: new XYZ({
        minZoom: 10,
        maxZoom: 16,
        url: 'https://3d.oslandia.com/dem/MtStHelens-tiles/{z}/{x}/{y}.tif',
    }),
    format: new GeoTIFFFormat(),
});

const floor = 1100;
const ceiling = 2500;

const values = colormap({ colormap: 'viridis', nshades: 256 });
const colors = values.map(v => new Color(v));

const dem = new ElevationLayer({
    name: 'dem',
    extent,
    interpretation: Interpretation.Raw,
    source,
    colorMap: new ColorMap(colors, floor, ceiling, ColorMapMode.Elevation),
});

map.addLayer(dem);

instance.camera.camera3D.position.set(-13600394, 5818579, 11832);

// Instanciates controls
const controls = new MapControls(instance.camera.camera3D, instance.domElement);

controls.target.set(-13603000, 5811000, 0);

instance.useTHREEControls(controls);

// GUI
function bindSlider(id, callback) {
    const slider = document.getElementById(id);
    slider.oninput = function oninput() {
        callback(slider.value);
        instance.notifyChange(map);
    };
}

function bindToggle(id, callback) {
    const toggle = document.getElementById(id);

    toggle.oninput = function oninput() {
        callback(toggle.checked);
        instance.notifyChange(map);
    };
}

function bindDropdown(id, callback) {
    document.getElementById(id).addEventListener('change', e => {
        callback(e.target.value);
        instance.notifyChange(map);
    });
}

bindToggle('toggle-graticule', v => (map.materialOptions.graticule.enabled = v));

bindSlider('x-step', v => (map.materialOptions.graticule.xStep = v));
bindSlider('y-step', v => (map.materialOptions.graticule.yStep = v));
bindSlider('x-offset', v => (map.materialOptions.graticule.xOffset = v));
bindSlider('y-offset', v => (map.materialOptions.graticule.yOffset = v));
bindSlider('opacity', v => (map.materialOptions.graticule.opacity = v));
bindSlider('thickness', v => (map.materialOptions.graticule.thickness = v));

bindDropdown('color', v => (map.materialOptions.graticule.color = new Color(v)));

Inspector.attach(document.getElementById('panelDiv'), instance);
index.html
<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="UTF-8">
  <title>Giro3D - Graticule</title>
  <link href="https://cdn.jsdelivr.net/npm/bootstrap@5.3.2/dist/css/bootstrap.min.css" rel="stylesheet" integrity="sha384-T3c6CoIi6uLrA9TneNEoa7RxnatzjcDSCmG1MXxSR1GAsXEV/Dwwykc2MPK8M2HN" crossorigin="anonymous">
  <link rel="stylesheet" href="https://cdn.jsdelivr.net/npm/bootstrap-icons@1.11.3/font/bootstrap-icons.min.css">
  <script src="https://cdn.jsdelivr.net/npm/bootstrap@5.3.2/dist/js/bootstrap.bundle.min.js" integrity="sha384-C6RzsynM9kWDrMNeT87bh95OGNyZPhcTNXj1NW7RuBCsyN/o0jlpcV8Qyq46cDfL" crossorigin="anonymous"></script>
  <style>
    body {
      padding: 0;
      margin: 0;
      width: 100vw;
      height: 100vh;
    }

    #viewerDiv {
      width: 100%;
      height: 100%;
    }

    #panelDiv {
      position: absolute;
      top: 0;
      left: 0;
    }
    
  </style>
</head>

<body>
  <div id="viewerDiv"></div>
  <div id="panelDiv"></div>
  <div class="m-2 position-absolute top-0 end-0">
    <div class="card">
        <div class="card-body">
            <!-- Show/Hide graticule -->
            <div class="form-check form-switch">
                <input
                    class="form-check-input"
                    type="checkbox"
                    checked="true"
                    role="switch"
                    id="toggle-graticule"
                    autocomplete="off"
                />
                <label class="form-check-label" for="toggle-graticule">Show graticule</label>
            </div>

            <div class="my-2"></div>

            <!-- X step -->
            <label for="x-step" class="form-label">X-axis step</label>
            <div class="input-group">
                <input
                    type="range"
                    min="100"
                    max="3000"
                    value="1000"
                    step="100"
                    class="form-range"
                    id="x-step"
                    autocomplete="off"
                />
            </div>

            <div class="my-2"></div>

            <!-- Y step -->
            <label for="y-step" class="form-label">Y-axis step</label>
            <div class="input-group">
                <input
                    type="range"
                    min="100"
                    max="3000"
                    value="1000"
                    step="100"
                    class="form-range"
                    id="y-step"
                    autocomplete="off"
                />
            </div>

            <div class="my-2"></div>

            <!-- X offset -->
            <label for="x-offset" class="form-label">X-axis offset</label>
            <div class="input-group">
                <input
                    type="range"
                    min="100"
                    max="3000"
                    value="200"
                    step="100"
                    class="form-range"
                    id="x-offset"
                    autocomplete="off"
                />
            </div>

            <div class="my-2"></div>

            <!-- Y offset -->
            <label for="y-offset" class="form-label">Y-axis offset</label>
            <div class="input-group">
                <input
                    type="range"
                    min="100"
                    max="3000"
                    value="200"
                    step="100"
                    class="form-range"
                    id="y-offset"
                    autocomplete="off"
                />
            </div>

            <div class="my-2"></div>

            <!-- Opacity -->
            <label for="opacity" class="form-label">Opacity</label>
            <div class="input-group">
                <input
                    type="range"
                    min="0"
                    max="1"
                    value="1"
                    step="0.01"
                    class="form-range"
                    id="opacity"
                    autocomplete="off"
                />
            </div>

            <!-- Thickness -->
            <label for="thickness" class="form-label">Thickness</label>
            <div class="input-group">
                <input
                    type="range"
                    min="1"
                    max="100"
                    value="20"
                    step="1"
                    class="form-range"
                    id="thickness"
                    autocomplete="off"
                />
            </div>

            <div class="my-2"></div>

            <!-- Color dropdown -->
            <div class="input-group">
                <span class="input-group-text flex-grow-1">Color</span>
                <select class="btn btn-outline-primary btn-sm" id="color" autocomplete="off">
                    <option selected value="white">White</option>
                    <option value="black">Black</option>
                    <option value="yellow">Yellow</option>
                    <option value="red">Red</option>
                </select>
            </div>
        </div>
    </div>
</div>

  <script type="module" src="index.js"></script>
  <script>
    /* activate popovers */
    const popoverTriggerList = [].slice.call(document.querySelectorAll('[data-bs-toggle="popover"]'));
    popoverTriggerList.map(
      // bootstrap is used as script in the template, disable warning about undef
      // eslint-disable-next-line no-undef
      popoverTriggerEl => new bootstrap.Popover(popoverTriggerEl, {
        trigger: 'hover',
        placement: 'left',
        content: document.getElementById(popoverTriggerEl.getAttribute('data-bs-content')).innerHTML,
        html: true,
      }),
    );
  </script>
</body>

</html>
package.json
{
  "name": "graticule",
  "dependencies": {
    "@giro3d/giro3d": "0.36.0",
    "colormap": "^2.3.2",
    "@turf/turf": "^6.5.0"
  },
  "devDependencies": {
    "vite": "^3.2.3"
  },
  "scripts": {
    "start": "vite",
    "build": "vite build"
  }
}