Files
openlayers/test/rendering/cases/webgl-tile-range/main.js
2021-12-23 17:50:49 -07:00

68 lines
1.5 KiB
JavaScript

import DataTile from '../../../../src/ol/source/DataTile.js';
import Map from '../../../../src/ol/Map.js';
import TileLayer from '../../../../src/ol/layer/WebGLTile.js';
import View from '../../../../src/ol/View.js';
import {Projection} from '../../../../src/ol/proj.js';
const size = 256;
const data = new Uint8Array(size * size * 4);
for (let row = 0; row < size; ++row) {
for (let col = 0; col < size; ++col) {
const index = (row * size + col) * 4;
data[index] = 0;
data[index + 1] = 255;
data[index + 2] = 0;
data[index + 3] = 255;
}
}
const canvas = document.createElement('canvas');
canvas.width = size;
canvas.height = size;
const context = canvas.getContext('2d');
context.strokeStyle = 'black';
function getLabels(z, x, y) {
context.clearRect(0, 0, size, size);
context.strokeRect(0, 0, size, size);
const data = context.getImageData(0, 0, size, size).data;
return new Uint8Array(data.buffer);
}
document.getElementById('map').style.background = 'red';
const projection = new Projection({
code: 'pixels',
units: 'pixels',
extent: [0, 0, 256, 256],
});
new Map({
target: 'map',
layers: [
new TileLayer({
source: new DataTile({
projection: projection,
maxZoom: 1,
tileSize: size,
loader: () => data,
}),
}),
new TileLayer({
source: new DataTile({
projection: projection,
loader: getLabels,
transition: 0,
}),
}),
],
view: new View({
projection: projection,
center: [127.7, 128.3],
zoom: 8,
}),
});
render();