itowns/lib/Converter/textureConverter.js

A JS/WebGL framework for 3D geospatial data visualization

import * as THREE from 'three';
import Feature2Texture from "./Feature2Texture.js";
import { Extent } from '@itowns/geographic';
const extentTexture = new Extent('EPSG:4326');
const textureLayer = (texture, layer) => {
  texture.generateMipmaps = false;
  texture.magFilter = layer.magFilter || THREE.LinearFilter;
  texture.minFilter = layer.minFilter || THREE.LinearFilter;
  return texture;
};
function textureColorLayer(texture, layer) {
  texture.anisotropy = 16;
  texture.premultiplyAlpha = layer.transparent;
  return textureLayer(texture, layer);
}
export default {
  convert(data, destinationTile, layer) {
    let texture;
    if (data.isFeatureCollection) {
      const backgroundLayer = layer.source.backgroundLayer;
      const backgroundColor = backgroundLayer && backgroundLayer.paint ? new THREE.Color(backgroundLayer.paint['background-color']) : undefined;
      destinationTile.toExtent(layer.crs, extentTexture);
      texture = Feature2Texture.createTextureFromFeature(data, extentTexture, layer.subdivisionThreshold, layer.style, backgroundColor);
      texture.features = data;
      texture.extent = destinationTile;
    } else if (data.isTexture) {
      texture = data;
    } else {
      throw new Error('Data type is not supported to convert into texture');
    }
    if (layer.isColorLayer) {
      return textureColorLayer(texture, layer);
    } else if (layer.isElevationLayer) {
      if (texture.flipY) {
        // DataTexture default to false, so make sure other Texture types
        // do the same (eg image texture)
        // See UV construction for more details
        texture.flipY = false;
      }
      return textureLayer(texture, layer);
    }
  }
};