Class: Aggregation

import {Aggregation} from '@int/geotoolkit/map/features/templates/Aggregation';
import {DefaultColorProvider} from '@int/geotoolkit/util/DefaultColorProvider';
const template = new Aggregation({
...
// change shape size dynamically:
'size': {
// size is based on the sum of aggregated features' population:
'field': 'population',
// size is changing from 25px to 60px:
'range': [25, 60]
},
'color': {
// no 'field' provided i.e. color is based on amount of aggregated features
// color 'range' can be either a color provider or an array:
'range': new DefaultColorProvider({
// use first color for 2 aggregated points, second for 50 and third for 500
// (linear interpolation):
'values': [2, 50, 500],
'colors': ['rgba(0, 0, 255, 0.5)', 'rgba(0, 0, 127, 0.5)', 'rgba(0, 0, 0, 0.5)']
})
}
});

const template = new Aggregation({
...
// change shape size dynamically:
'size': {
// 'field' can be a function, here's a callback to calculate the average 'age' of aggregated features:
'field': (feature) => {
let sum = 0, count = 0;
feature.getAggregation().forEach((element) => {
sum += +element.getAttributes()['age']; // add 'age' value
count++; // count the processed elements
});
return sum / count; // return average 'age' value
},
// now size is based on the average 'age' value:
'range': [25, 60]
},
'color': {
// color is based on the sum of aggregated features' priority:
'field': 'priority',
// color 'range' can be either a color provider or an array:
// color changes from white to black basing on priority:
'range': ['white', 'black']
}
});