@loaders.gl/tiles
Version:
Common components for different tiles loaders.
52 lines (51 loc) • 2.12 kB
JavaScript
// loaders.gl
// SPDX-License-Identifier: MIT
// Copyright (c) vis.gl contributors
import { Ellipsoid } from '@math.gl/geospatial';
import { Matrix4, Vector3 } from '@math.gl/core';
import { assert } from '@loaders.gl/loader-utils';
export function calculateTransformProps(tileHeader, tile) {
assert(tileHeader);
assert(tile);
const { rtcCenter, gltfUpAxis } = tile;
const { computedTransform, boundingVolume: { center } } = tileHeader;
let modelMatrix = new Matrix4(computedTransform);
// Translate if appropriate
if (rtcCenter) {
modelMatrix.translate(rtcCenter);
}
// glTF models need to be rotated from Y to Z up
// https://github.com/AnalyticalGraphicsInc/3d-tiles/tree/master/specification#y-up-to-z-up
switch (gltfUpAxis) {
case 'Z':
break;
case 'Y':
const rotationY = new Matrix4().rotateX(Math.PI / 2);
modelMatrix = modelMatrix.multiplyRight(rotationY);
break;
case 'X':
const rotationX = new Matrix4().rotateY(-Math.PI / 2);
modelMatrix = modelMatrix.multiplyRight(rotationX);
break;
default:
break;
}
// Scale/offset positions if normalized integers
if (tile.isQuantized) {
modelMatrix.translate(tile.quantizedVolumeOffset).scale(tile.quantizedVolumeScale);
}
// Option 1: Cartesian matrix and origin
const cartesianOrigin = new Vector3(center);
tile.cartesianModelMatrix = modelMatrix;
tile.cartesianOrigin = cartesianOrigin;
// Option 2: Cartographic matrix and origin
const cartographicOrigin = Ellipsoid.WGS84.cartesianToCartographic(cartesianOrigin, new Vector3());
const fromFixedFrameMatrix = Ellipsoid.WGS84.eastNorthUpToFixedFrame(cartesianOrigin);
const toFixedFrameMatrix = fromFixedFrameMatrix.invert();
tile.cartographicModelMatrix = toFixedFrameMatrix.multiplyRight(modelMatrix);
tile.cartographicOrigin = cartographicOrigin;
// Deprecated, drop
if (!tile.coordinateSystem) {
tile.modelMatrix = tile.cartographicModelMatrix;
}
}