To boldly geo where no-one has geo'd before
Public
Edited
Feb 6, 2024
1 star
horseland = getImage([106791.4,527778.4],250)
//ahnurl = "https://ahp-research.storage.googleapis.com/rasters/bodemdaling/ahn_diff.tif" //'https://ahn_data.storage.googleapis.com/M_25EN1_cog.TIF'
ahn3url = "https://ahp-research.storage.googleapis.com/rasters/ahn4_05m_dtm_cog.tiff"
ahn2url = "https://ahp-research.storage.googleapis.com/rasters/ahn3_05m_dtm_cog.tiff"
ahn4_vrt = "https://storage.googleapis.com/ahp-research/rasters/ahn4_dtm_05m_4326/ahn4_05m_dtm_cogs/ahn4_05m_dtm_4326.vrt"
async function getImage(center, radius, mapnr){
let extent = [
center[0] - radius,
center[1] - radius,
center[0] + radius,
center[1] + radius
];
let data1 = await getDiffImage(extent);
let data2 = await getLufo(extent,'2016_ortho25');
let data3 = await getLufo(extent,'2020_ortho25');
return drawtriplet(data1.bitmap,data2,data3,data1.rasters);
}
getImageTest = getImage([123757.3,483865.8],100)
async function getDiffImage(extent){
const data2 = await getData(ahn2url, extent);
const data3 = await getData(ahn3url, extent);
let retraster = new Float32Array(data2[0].length);
for (let i=0;i<data2[0].length;i++){
retraster[i] = data3[0][i] - data2[0][i];
}
let { width, height } = data2;
const data = new Uint8ClampedArray(width * height * 4);
let colorextent = d3.extent(retraster.filter(d=>d<1000 && d>-1000));
for (let i = 0; i < retraster.length; i++) {
let color = d3.color(getColor(retraster[i],colorextent));
data[i * 4 + 0] = color.r;
data[i * 4 + 1] = color.g;
data[i * 4 + 2] = color.b;
data[i * 4 + 3] = retraster[i] > 3000 ? 0 : 255;
}
let imgdata = new ImageData(data, width, height);
let bitmap = await createImageBitmap(imgdata);
return {bitmap,retraster};
}
getAHNTest = getDiffImage([123757.3-100,483865.8-100,123757.3+100,483865.8+100])
async function getData(url, extent){
const cog = await geotiff.fromUrl(url);
const img = await cog.getImage(0);
const bbox = img.getBoundingBox();
const scale = 2;
const window = [
~~(extent[0] - bbox[0]) * scale,
~~(bbox[3] - extent[3]) * scale,
~~(extent[2] - bbox[0]) * scale,
~~(bbox[3] - extent[1]) * scale
];
const rasters = await img.readRasters({
pool,
window: window,
width: size,
height: size,
resampleMethod: 'bilinear'
});
return rasters;
}
getDataTest = getData(ahn2url, [123757.3-100,483865.8-100, 123757.3+100,483865.8+100])
d3.extent(getAHNTest.retraster.filter(d=>d<1000 && d>-1000))
function getColor(value, extent){
let colorscale = d3.scaleDivergingSymlog()
.domain([extent[1],0,extent[0]])
.interpolator(d3.interpolateBrBG);
return colorscale(value);
}
async function getLufo(extent,layername){
let img = new Image();
img.crossOrigin = '*';
let params = wmsurl.searchParams;
params.set('layers',layername)
params.set('width',size)
params.set('height',size)
params.set('bbox',extent.join(','))
img.src = wmsurl.toString();
await new Promise(resolve => img.addEventListener('load', resolve));
return img;
}
function drawtriplet(data1, data2,data3,rasters){
let c = DOM.context2d((size+5) * 3, size, 1);
c.drawImage(data1, 0, 0, size, size);
c.drawImage(data2,size + 5,0,size,size);
c.drawImage(data3,2*(size + 5),0,size,size);
c.canvas.addEventListener('mousemove', function(e) {
c.drawImage(data1, 0, 0);
var pos = findPos(this);
var x = e.pageX - pos.x;
var y = e.pageY - pos.y;
if (x <= size) {
let value = rasters[0][x+(size*y)];
if (value < 1000){
let displaytext = Math.round(value*1000,2)/1000;
c.font = 'small-caps bolder 10px serif';
c.strokeStyle = '#FFFFFF';
c.strokeText(displaytext, x+10, y-5);
c.fillStyle = '#550000';
c.textBaseline = 'top';
c.fillText ( displaytext, x+10, y-5);
}
}
});
return c.canvas;
}
geotiff = require('geotiff@2.0.4/dist-browser/geotiff.js')
parseGeoRaster = require("georaster")
pool = new geotiff.Pool();
d3 = require("d3@6", "d3-geo-projection@3")
tween = require('tween.js')
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