@deck.gl/layers
Version:
deck.gl core layers
47 lines (46 loc) • 1.74 kB
JavaScript
// This module implement some utility functions to work with
// the geojson-binary format defined at loaders.gl:
// https://github.com/visgl/loaders.gl/blob/master/modules/gis/docs/api-reference/geojson-to-binary.md
/**
* Return the feature for an accesor
*/
export function binaryToFeatureForAccesor(data, index) {
if (!data) {
return null;
}
const featureIndex = 'startIndices' in data ? data.startIndices[index] : index;
const geometryIndex = data.featureIds.value[featureIndex];
if (featureIndex !== -1) {
return getPropertiesForIndex(data, geometryIndex, featureIndex);
}
return null;
}
function getPropertiesForIndex(data, propertiesIndex, numericPropsIndex) {
const feature = {
properties: { ...data.properties[propertiesIndex] }
};
for (const prop in data.numericProps) {
feature.properties[prop] = data.numericProps[prop].value[numericPropsIndex];
}
return feature;
}
// Custom picking color to keep binary indexes
export function calculatePickingColors(geojsonBinary, encodePickingColor) {
const pickingColors = {
points: null,
lines: null,
polygons: null
};
for (const key in pickingColors) {
const featureIds = geojsonBinary[key].globalFeatureIds.value;
pickingColors[key] = new Uint8ClampedArray(featureIds.length * 3);
const pickingColor = [];
for (let i = 0; i < featureIds.length; i++) {
encodePickingColor(featureIds[i], pickingColor);
pickingColors[key][i * 3 + 0] = pickingColor[0];
pickingColors[key][i * 3 + 1] = pickingColor[1];
pickingColors[key][i * 3 + 2] = pickingColor[2];
}
}
return pickingColors;
}