import when from '../ThirdParty/when.js';
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import Cartesian2 from './Cartesian2.js';
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import defined from './defined.js';
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import DeveloperError from './DeveloperError.js';
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import sampleTerrain from './sampleTerrain.js';
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var scratchCartesian2 = new Cartesian2();
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/**
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* Initiates a sampleTerrain() request at the maximum available tile level for a terrain dataset.
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*
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* @exports sampleTerrainMostDetailed
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*
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* @param {TerrainProvider} terrainProvider The terrain provider from which to query heights.
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* @param {Cartographic[]} positions The positions to update with terrain heights.
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* @returns {Promise.<Cartographic[]>} A promise that resolves to the provided list of positions when terrain the query has completed. This
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* promise will reject if the terrain provider's `availability` property is undefined.
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*
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* @example
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* // Query the terrain height of two Cartographic positions
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* var terrainProvider = Cesium.createWorldTerrain();
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* var positions = [
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* Cesium.Cartographic.fromDegrees(86.925145, 27.988257),
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* Cesium.Cartographic.fromDegrees(87.0, 28.0)
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* ];
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* var promise = Cesium.sampleTerrainMostDetailed(terrainProvider, positions);
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* Cesium.when(promise, function(updatedPositions) {
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* // positions[0].height and positions[1].height have been updated.
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* // updatedPositions is just a reference to positions.
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* });
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*/
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function sampleTerrainMostDetailed(terrainProvider, positions) {
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//>>includeStart('debug', pragmas.debug);
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if (!defined(terrainProvider)) {
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throw new DeveloperError('terrainProvider is required.');
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}
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if (!defined(positions)) {
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throw new DeveloperError('positions is required.');
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}
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//>>includeEnd('debug');
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return terrainProvider.readyPromise
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.then(function() {
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var byLevel = [];
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var maxLevels = [];
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var availability = terrainProvider.availability;
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//>>includeStart('debug', pragmas.debug);
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if (!defined(availability)) {
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throw new DeveloperError('sampleTerrainMostDetailed requires a terrain provider that has tile availability.');
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}
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//>>includeEnd('debug');
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var promises = [];
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for (var i = 0; i < positions.length; ++i) {
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var position = positions[i];
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var maxLevel = availability.computeMaximumLevelAtPosition(position);
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maxLevels[i] = maxLevel;
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if (maxLevel === 0) {
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// This is a special case where we have a parent terrain and we are requesting
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// heights from an area that isn't covered by the top level terrain at all.
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// This will essentially trigger the loading of the parent terrains root tile
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terrainProvider.tilingScheme.positionToTileXY(position, 1, scratchCartesian2);
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var promise = terrainProvider.loadTileDataAvailability(scratchCartesian2.x, scratchCartesian2.y, 1);
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if (defined(promise)) {
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promises.push(promise);
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}
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}
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var atLevel = byLevel[maxLevel];
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if (!defined(atLevel)) {
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byLevel[maxLevel] = atLevel = [];
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}
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atLevel.push(position);
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}
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return when.all(promises)
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.then(function() {
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return when.all(byLevel.map(function(positionsAtLevel, index) {
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if (defined(positionsAtLevel)) {
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return sampleTerrain(terrainProvider, index, positionsAtLevel);
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}
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}));
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})
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.then(function() {
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var changedPositions = [];
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for (var i = 0; i < positions.length; ++i) {
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var position = positions[i];
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var maxLevel = availability.computeMaximumLevelAtPosition(position);
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if (maxLevel !== maxLevels[i]) {
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// Now that we loaded the max availability, a higher level has become available
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changedPositions.push(position);
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}
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}
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if (changedPositions.length > 0) {
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return sampleTerrainMostDetailed(terrainProvider, changedPositions);
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}
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})
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.then(function() {
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return positions;
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});
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});
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}
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export default sampleTerrainMostDetailed;
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