Merge pull request #10094 from ahocevar/immediate-hitdetection

New Layer#getFeatures method with fast hit detection

examples/hitdetect-vector.html

@@ -0,0 +1,15 @@
+---
+layout: example.html
+title: Vector Layer Hit Detection
+shortdesc: Example of hit detection on a countries vector layer with country information.
+docs: >
+  The countries are loaded from a GeoJSON file. Information about countries is
+  on hover and click is retrieved using the layer's `getFeatures()` method. For
+  vector layers, this function resolves with an array of only the topmost
+  feature. It uses a very efficient hit detection algorithm, at the cost of
+  accuracy. For pixel exact hit detection, when performance is not a concern,
+  use the map's `getFeaturesAtPixel()` or `forEachFeatureAtPixel()` methods.
+tags: "vector, geojson, click, hover, hit detection"
+---
+<div id="map" class="map"></div>
+<div id="info">&nbsp;</div>

examples/hitdetect-vector.js

@@ -0,0 +1,113 @@
+import Map from '../src/ol/Map.js';
+import View from '../src/ol/View.js';
+import GeoJSON from '../src/ol/format/GeoJSON.js';
+import VectorLayer from '../src/ol/layer/Vector.js';
+import VectorSource from '../src/ol/source/Vector.js';
+import {Fill, Stroke, Style, Text} from '../src/ol/style.js';
+
+
+const style = new Style({
+  fill: new Fill({
+    color: 'rgba(255, 255, 255, 0.6)'
+  }),
+  stroke: new Stroke({
+    color: '#319FD3',
+    width: 1
+  }),
+  text: new Text({
+    font: '12px Calibri,sans-serif',
+    fill: new Fill({
+      color: '#000'
+    }),
+    stroke: new Stroke({
+      color: '#fff',
+      width: 3
+    })
+  })
+});
+
+const vectorLayer = new VectorLayer({
+  source: new VectorSource({
+    url: 'data/geojson/countries.geojson',
+    format: new GeoJSON()
+  }),
+  style: function(feature) {
+    style.getText().setText(feature.get('name'));
+    return style;
+  }
+});
+
+const map = new Map({
+  layers: [vectorLayer],
+  target: 'map',
+  view: new View({
+    center: [0, 0],
+    zoom: 1
+  })
+});
+
+const highlightStyle = new Style({
+  stroke: new Stroke({
+    color: '#f00',
+    width: 1
+  }),
+  fill: new Fill({
+    color: 'rgba(255,0,0,0.1)'
+  }),
+  text: new Text({
+    font: '12px Calibri,sans-serif',
+    fill: new Fill({
+      color: '#000'
+    }),
+    stroke: new Stroke({
+      color: '#f00',
+      width: 3
+    })
+  })
+});
+
+const featureOverlay = new VectorLayer({
+  source: new VectorSource(),
+  map: map,
+  style: function(feature) {
+    highlightStyle.getText().setText(feature.get('name'));
+    return highlightStyle;
+  }
+});
+
+let highlight;
+const displayFeatureInfo = function(pixel) {
+
+  vectorLayer.getFeatures(pixel).then(function(features) {
+    const feature = features.length ? features[0] : undefined;
+    const info = document.getElementById('info');
+    if (features.length) {
+      info.innerHTML = feature.getId() + ': ' + feature.get('name');
+    } else {
+      info.innerHTML = ' ';
+    }
+
+    if (feature !== highlight) {
+      if (highlight) {
+        featureOverlay.getSource().removeFeature(highlight);
+      }
+      if (feature) {
+        featureOverlay.getSource().addFeature(feature);
+      }
+      highlight = feature;
+    }
+  });
+
+};
+
+map.on('pointermove', function(evt) {
+  if (evt.dragging) {
+    return;
+  }
+  const pixel = map.getEventPixel(evt.originalEvent);
+  displayFeatureInfo(pixel);
+});
+
+map.on('click', function(evt) {
+  displayFeatureInfo(evt.pixel);
+});

examples/vector-tile-selection.js

@@ -45,26 +45,27 @@ const map = new Map({
 const selectElement = document.getElementById('type');
 
 map.on('click', function(event) {
-  const features = map.getFeaturesAtPixel(event.pixel);
-  if (!features) {
-    selection = {};
+  vtLayer.getFeatures(event.pixel).then(function(features) {
+    if (!features.length) {
+      selection = {};
+      // force redraw of layer style
+      vtLayer.setStyle(vtLayer.getStyle());
+      return;
+    }
+    const feature = features[0];
+    if (!feature) {
+      return;
+    }
+    const fid = feature.get(idProp);
+
+    if (selectElement.value === 'singleselect') {
+      selection = {};
+    }
+    // add selected feature to lookup
+    selection[fid] = feature;
+
     // force redraw of layer style
     vtLayer.setStyle(vtLayer.getStyle());
-    return;
-  }
-  const feature = features[0];
-  if (!feature) {
-    return;
-  }
+  });
 
-  const fid = feature.get(idProp);
-
-  if (selectElement.value === 'singleselect') {
-    selection = {};
-  }
-  // add selected feature to lookup
-  selection[fid] = feature;
-
-  // force redraw of layer style
-  vtLayer.setStyle(vtLayer.getStyle());
 });

src/ol/Tile.js

@@ -87,6 +87,11 @@ class Tile extends EventTarget {
 
     const options = opt_options ? opt_options : {};
 
+    /**
+     * @type {ImageData}
+     */
+    this.hitDetectionImageData = null;
+
     /**
      * @type {import("./tilecoord.js").TileCoord}
      */

src/ol/layer/BaseVector.js

@@ -135,6 +135,24 @@ class BaseVectorLayer extends Layer {
     return this.declutter_;
   }
 
+  /**
+   * Get the topmost feature that intersects the given pixel on the viewport. Returns a promise
+   * that resolves with an array of features. The array will either contain the topmost feature
+   * when a hit was detected, or it will be empty.
+   *
+   * The hit detection algorithm used for this method is optimized for performance, but is less
+   * accurate than the one used in {@link import("../PluggableMap.js").default#getFeaturesAtPixel}: Text
+   * is not considered, and icons are only represented by their bounding box instead of the exact
+   * image.
+   *
+   * @param {import("../pixel.js").Pixel} pixel Pixel.
+   * @return {Promise<Array<import("../Feature").default>>} Promise that resolves with an array of features.
+   * @api
+   */
+  getFeatures(pixel) {
+    return super.getFeatures(pixel);
+  }
+
   /**
    * @return {number|undefined} Render buffer.
    */

src/ol/layer/Layer.js

@@ -192,6 +192,15 @@ class Layer extends BaseLayer {
     this.changed();
   }
 
+  /**
+   * @param {import("../pixel").Pixel} pixel Pixel.
+   * @return {Promise<Array<import("../Feature").default>>} Promise that resolves with
+   * an array of features.
+   */
+  getFeatures(pixel) {
+    return this.renderer_.getFeatures(pixel);
+  }
+
   /**
    * In charge to manage the rendering of the layer. One layer type is
    * bounded with one layer renderer.

src/ol/layer/VectorTile.js

@@ -116,6 +116,24 @@ class VectorTileLayer extends BaseVectorLayer {
     return new CanvasVectorTileLayerRenderer(this);
   }
 
+  /**
+   * Get the topmost feature that intersects the given pixel on the viewport. Returns a promise
+   * that resolves with an array of features. The array will either contain the topmost feature
+   * when a hit was detected, or it will be empty.
+   *
+   * The hit detection algorithm used for this method is optimized for performance, but is less
+   * accurate than the one used in {@link import("../PluggableMap.js").default#getFeaturesAtPixel}: Text
+   * is not considered, and icons are only represented by their bounding box instead of the exact
+   * image.
+   *
+   * @param {import("../pixel.js").Pixel} pixel Pixel.
+   * @return {Promise<Array<import("../Feature").default>>} Promise that resolves with an array of features.
+   * @api
+   */
+  getFeatures(pixel) {
+    return super.getFeatures(pixel);
+  }
+
   /**
    * @return {VectorTileRenderType} The render mode.
    */

src/ol/render/canvas/Immediate.js

@@ -15,6 +15,7 @@ import VectorContext from '../VectorContext.js';
 import {defaultTextAlign, defaultFillStyle, defaultLineCap, defaultLineDash, defaultLineDashOffset, defaultLineJoin, defaultLineWidth, defaultMiterLimit, defaultStrokeStyle, defaultTextBaseline, defaultFont} from '../canvas.js';
 import {create as createTransform, compose as composeTransform} from '../../transform.js';
 
+
 /**
  * @classdesc
  * A concrete subclass of {@link module:ol/render/VectorContext} that implements
@@ -438,6 +439,13 @@ class CanvasImmediateRenderer extends VectorContext {
     this.setTextStyle(style.getText());
   }
 
+  /**
+   * @param {import("../../transform.js").Transform} transform Transform.
+   */
+  setTransform(transform) {
+    this.transform_ = transform;
+  }
+
   /**
    * Render a geometry into the canvas.  Call
    * {@link module:ol/render/canvas/Immediate#setStyle} first to set the rendering style.

src/ol/render/canvas/hitdetect.js

@@ -0,0 +1,146 @@
+/**
+ * @module ol/render/canvas/hitdetet
+ */
+
+import CanvasImmediateRenderer from './Immediate.js';
+import {createCanvasContext2D} from '../../dom.js';
+import {Icon} from '../../style.js';
+import IconAnchorUnits from '../../style/IconAnchorUnits.js';
+import GeometryType from '../../geom/GeometryType.js';
+import {intersects} from '../../extent.js';
+import {numberSafeCompareFunction} from '../../array.js';
+
+/**
+ * @param {import("../../size.js").Size} size Canvas size in css pixels.
+ * @param {Array<import("../../transform.js").Transform>} transforms Transforms
+ * for rendering features to all worlds of the viewport, from coordinates to css
+ * pixels.
+ * @param {Array<import("../../Feature.js").FeatureLike>} features
+ * Features to consider for hit detection.
+ * @param {import("../../style/Style.js").StyleFunction|undefined} styleFunction
+ * Layer style function.
+ * @param {import("../../extent.js").Extent} extent Extent.
+ * @param {number} resolution Resolution.
+ * @param {number} rotation Rotation.
+ * @return {ImageData} Hit detection image data.
+ */
+export function createHitDetectionImageData(size, transforms, features, styleFunction, extent, resolution, rotation) {
+  const width = size[0] / 2;
+  const height = size[1] / 2;
+  const context = createCanvasContext2D(width, height);
+  context.imageSmoothingEnabled = false;
+  const canvas = context.canvas;
+  const renderer = new CanvasImmediateRenderer(context, 0.5, extent, null, rotation);
+  const featureCount = features.length;
+  // Stretch hit detection index to use the whole available color range
+  const indexFactor = Math.ceil((256 * 256 * 256) / featureCount);
+  const featuresByZIndex = {};
+  for (let i = 0; i < featureCount; ++i) {
+    const feature = features[i];
+    const featureStyleFunction = feature.getStyleFunction() || styleFunction;
+    if (!styleFunction) {
+      continue;
+    }
+    let styles = featureStyleFunction(feature, resolution);
+    if (!Array.isArray(styles)) {
+      styles = [styles];
+    }
+    const index = i * indexFactor;
+    const color = '#' + ('000000' + index.toString(16)).slice(-6);
+    for (let j = 0, jj = styles.length; j < jj; ++j) {
+      const originalStyle = styles[j];
+      const style = originalStyle.clone();
+      const fill = style.getFill();
+      if (fill) {
+        fill.setColor(color);
+      }
+      const stroke = style.getStroke();
+      if (stroke) {
+        stroke.setColor(color);
+      }
+      style.setText(undefined);
+      const image = originalStyle.getImage();
+      if (image) {
+        const imgSize = image.getImageSize();
+        const imgContext = createCanvasContext2D(imgSize[0], imgSize[1]);
+        imgContext.fillStyle = color;
+        const img = imgContext.canvas;
+        imgContext.fillRect(0, 0, img.width, img.height);
+        const width = imgSize ? imgSize[0] : img.width;
+        const height = imgSize ? imgSize[1] : img.height;
+        const iconContext = createCanvasContext2D(width, height);
+        iconContext.drawImage(img, 0, 0);
+        style.setImage(new Icon({
+          img: img,
+          imgSize: imgSize,
+          anchor: image.getAnchor(),
+          anchorXUnits: IconAnchorUnits.PIXELS,
+          anchorYUnits: IconAnchorUnits.PIXELS,
+          offset: image.getOrigin(),
+          size: image.getSize(),
+          opacity: image.getOpacity(),
+          scale: image.getScale(),
+          rotation: image.getRotation(),
+          rotateWithView: image.getRotateWithView()
+        }));
+      }
+      const zIndex = Number(style.getZIndex());
+      let byGeometryType = featuresByZIndex[zIndex];
+      if (!byGeometryType) {
+        byGeometryType = featuresByZIndex[zIndex] = {};
+        byGeometryType[GeometryType.POLYGON] = [];
+        byGeometryType[GeometryType.CIRCLE] = [];
+        byGeometryType[GeometryType.LINE_STRING] = [];
+        byGeometryType[GeometryType.POINT] = [];
+      }
+      const geometry = style.getGeometryFunction()(feature);
+      if (geometry && intersects(extent, geometry.getExtent())) {
+        byGeometryType[geometry.getType().replace('Multi', '')].push(geometry, style);
+      }
+    }
+  }
+
+  const zIndexKeys = Object.keys(featuresByZIndex).map(Number).sort(numberSafeCompareFunction);
+  for (let i = 0, ii = zIndexKeys.length; i < ii; ++i) {
+    const byGeometryType = featuresByZIndex[zIndexKeys[i]];
+    for (const type in byGeometryType) {
+      const geomAndStyle = byGeometryType[type];
+      for (let j = 0, jj = geomAndStyle.length; j < jj; j += 2) {
+        renderer.setStyle(geomAndStyle[j + 1]);
+        for (let k = 0, kk = transforms.length; k < kk; ++k) {
+          renderer.setTransform(transforms[k]);
+          renderer.drawGeometry(geomAndStyle[j]);
+        }
+      }
+    }
+  }
+  return context.getImageData(0, 0, canvas.width, canvas.height);
+}
+
+/**
+ * @param {import("../../pixel").Pixel} pixel Pixel coordinate on the hit
+ * detection canvas in css pixels.
+ * @param {Array<import("../../Feature").FeatureLike>} features Features. Has to
+ * match the `features` array that was passed to `createHitDetectionImageData()`.
+ * @param {ImageData} imageData Hit detection image data generated by
+ * `createHitDetectionImageData()`.
+ * @return {Array<import("../../Feature").FeatureLike>} features Features.
+ */
+export function hitDetect(pixel, features, imageData) {
+  const resultFeatures = [];
+  if (imageData) {
+    const index = (Math.round(pixel[0] / 2) + Math.round(pixel[1] / 2) * imageData.width) * 4;
+    const r = imageData.data[index];
+    const g = imageData.data[index + 1];
+    const b = imageData.data[index + 2];
+    const a = imageData.data[index + 3];
+    if (a === 255) {
+      const i = b + (256 * (g + (256 * r)));
+      const indexFactor = Math.ceil((256 * 256 * 256) / features.length);
+      if (i % indexFactor === 0) {
+        resultFeatures.push(features[i / indexFactor]);
+      }
+    }
+  }
+  return resultFeatures;
+}

src/ol/renderer/Layer.js

@@ -30,6 +30,16 @@ class LayerRenderer extends Observable {
 
   }
 
+  /**
+   * Asynchronous layer level hit detection.
+   * @param {import("../pixel.js").Pixel} pixel Pixel.
+   * @return {Promise<Array<import("../Feature").default>>} Promise that resolves with
+   * an array of features.
+   */
+  getFeatures(pixel) {
+    return abstract();
+  }
+
   /**
    * Determine whether render should be called.
    * @abstract

src/ol/renderer/canvas/Layer.js

@@ -214,23 +214,24 @@ class CanvasLayerRenderer extends LayerRenderer {
 
   /**
    * Creates a transform for rendering to an element that will be rotated after rendering.
-   * @param {import("../../PluggableMap.js").FrameState} frameState Frame state.
+   * @param {import("../../coordinate.js").Coordinate} center Center.
+   * @param {number} resolution Resolution.
+   * @param {number} rotation Rotation.
+   * @param {number} pixelRatio Pixel ratio.
    * @param {number} width Width of the rendered element (in pixels).
    * @param {number} height Height of the rendered element (in pixels).
    * @param {number} offsetX Offset on the x-axis in view coordinates.
    * @protected
    * @return {!import("../../transform.js").Transform} Transform.
    */
-  getRenderTransform(frameState, width, height, offsetX) {
-    const viewState = frameState.viewState;
-    const pixelRatio = frameState.pixelRatio;
+  getRenderTransform(center, resolution, rotation, pixelRatio, width, height, offsetX) {
     const dx1 = width / 2;
     const dy1 = height / 2;
-    const sx = pixelRatio / viewState.resolution;
+    const sx = pixelRatio / resolution;
     const sy = -sx;
-    const dx2 = -viewState.center[0] + offsetX;
-    const dy2 = -viewState.center[1];
-    return composeTransform(this.tempTransform_, dx1, dy1, sx, sy, -viewState.rotation, dx2, dy2);
+    const dx2 = -center[0] + offsetX;
+    const dy2 = -center[1];
+    return composeTransform(this.tempTransform_, dx1, dy1, sx, sy, -rotation, dx2, dy2);
   }
 
   /**

src/ol/renderer/canvas/TileLayer.js

@@ -35,6 +35,18 @@ class CanvasTileLayerRenderer extends CanvasLayerRenderer {
      */
     this.renderedExtent_ = null;
 
+    /**
+     * @protected
+     * @type {number}
+     */
+    this.renderedPixelRatio;
+
+    /**
+     * @protected
+     * @type {import("../../proj/Projection.js").default}
+     */
+    this.renderedProjection = null;
+
     /**
      * @protected
      * @type {number}
@@ -342,6 +354,8 @@ class CanvasTileLayerRenderer extends CanvasLayerRenderer {
     this.renderedResolution = tileResolution;
     this.extentChanged = !this.renderedExtent_ || !equals(this.renderedExtent_, canvasExtent);
     this.renderedExtent_ = canvasExtent;
+    this.renderedPixelRatio = pixelRatio;
+    this.renderedProjection = projection;
 
     this.manageTilePyramid(frameState, tileSource, tileGrid, pixelRatio,
       projection, extent, z, tileLayer.getPreload());

src/ol/renderer/canvas/VectorLayer.js

@@ -9,7 +9,8 @@ import CanvasBuilderGroup from '../../render/canvas/BuilderGroup.js';
 import ExecutorGroup, {replayDeclutter} from '../../render/canvas/ExecutorGroup.js';
 import CanvasLayerRenderer from './Layer.js';
 import {defaultOrder as defaultRenderOrder, getTolerance as getRenderTolerance, getSquaredTolerance as getSquaredRenderTolerance, renderFeature} from '../vector.js';
-import {toString as transformToString, makeScale, makeInverse} from '../../transform.js';
+import {toString as transformToString, makeScale, makeInverse, apply} from '../../transform.js';
+import {createHitDetectionImageData, hitDetect} from '../../render/canvas/hitdetect.js';
 
 /**
  * @classdesc
@@ -28,6 +29,10 @@ class CanvasVectorLayerRenderer extends CanvasLayerRenderer {
     /** @private */
     this.boundHandleStyleImageChange_ = this.handleStyleImageChange_.bind(this);
 
+    /**
+     * @type {boolean}
+     */
+    this.animatingOrInteracting_;
 
     /**
      * @private
@@ -35,6 +40,16 @@ class CanvasVectorLayerRenderer extends CanvasLayerRenderer {
      */
     this.dirty_ = false;
 
+    /**
+     * @type {ImageData}
+     */
+    this.hitDetectionImageData_ = null;
+
+    /**
+     * @type {Array<import("../../Feature.js").default>}
+     */
+    this.renderedFeatures_ = null;
+
     /**
      * @private
      * @type {number}
@@ -53,6 +68,24 @@ class CanvasVectorLayerRenderer extends CanvasLayerRenderer {
      */
     this.renderedExtent_ = createEmpty();
 
+    /**
+     * @private
+     * @type {number}
+     */
+    this.renderedRotation_;
+
+    /**
+     * @private
+     * @type {import("../../coordinate").Coordinate}
+     */
+    this.renderedCenter_ = null;
+
+    /**
+     * @private
+     * @type {import("../../proj/Projection").default}
+     */
+    this.renderedProjection_ = null;
+
     /**
      * @private
      * @type {function(import("../../Feature.js").default, import("../../Feature.js").default): number|null}
@@ -124,6 +157,8 @@ class CanvasVectorLayerRenderer extends CanvasLayerRenderer {
 
     const extent = frameState.extent;
     const viewState = frameState.viewState;
+    const center = viewState.center;
+    const resolution = viewState.resolution;
     const projection = viewState.projection;
     const rotation = viewState.rotation;
     const projectionExtent = projection.getExtent();
@@ -143,7 +178,7 @@ class CanvasVectorLayerRenderer extends CanvasLayerRenderer {
     const viewHints = frameState.viewHints;
     const snapToPixel = !(viewHints[ViewHint.ANIMATING] || viewHints[ViewHint.INTERACTING]);
 
-    const transform = this.getRenderTransform(frameState, width, height, 0);
+    const transform = this.getRenderTransform(center, resolution, rotation, pixelRatio, width, height, 0);
     const declutterReplays = this.getLayer().getDeclutter() ? {} : null;
     replayGroup.execute(context, transform, rotation, snapToPixel, undefined, declutterReplays);
 
@@ -155,7 +190,7 @@ class CanvasVectorLayerRenderer extends CanvasLayerRenderer {
       while (startX < projectionExtent[0]) {
         --world;
         offsetX = worldWidth * world;
-        const transform = this.getRenderTransform(frameState, width, height, offsetX);
+        const transform = this.getRenderTransform(center, resolution, rotation, pixelRatio, width, height, offsetX);
         replayGroup.execute(context, transform, rotation, snapToPixel, undefined, declutterReplays);
         startX += worldWidth;
       }
@@ -164,7 +199,7 @@ class CanvasVectorLayerRenderer extends CanvasLayerRenderer {
       while (startX > projectionExtent[2]) {
         ++world;
         offsetX = worldWidth * world;
-        const transform = this.getRenderTransform(frameState, width, height, offsetX);
+        const transform = this.getRenderTransform(center, resolution, rotation, pixelRatio, width, height, offsetX);
         replayGroup.execute(context, transform, rotation, snapToPixel, undefined, declutterReplays);
         startX -= worldWidth;
       }
@@ -190,6 +225,58 @@ class CanvasVectorLayerRenderer extends CanvasLayerRenderer {
     return this.container;
   }
 
+  /**
+   * @inheritDoc
+   */
+  getFeatures(pixel) {
+    return new Promise(function(resolve, reject) {
+      if (!this.hitDetectionImageData_ && !this.animatingOrInteracting_) {
+        requestAnimationFrame(function() {
+          const size = [this.context.canvas.width, this.context.canvas.height];
+          apply(this.pixelTransform, size);
+          const center = this.renderedCenter_;
+          const resolution = this.renderedResolution_;
+          const rotation = this.renderedRotation_;
+          const projection = this.renderedProjection_;
+          const extent = this.renderedExtent_;
+          const layer = this.getLayer();
+          const transforms = [];
+          const width = size[0] / 2;
+          const height = size[1] / 2;
+          transforms.push(this.getRenderTransform(center, resolution, rotation, 0.5, width, height, 0).slice());
+          const source = layer.getSource();
+          const projectionExtent = projection.getExtent();
+          if (source.getWrapX() && projection.canWrapX() && !containsExtent(projectionExtent, extent)) {
+            let startX = extent[0];
+            const worldWidth = getWidth(projectionExtent);
+            let world = 0;
+            let offsetX;
+            while (startX < projectionExtent[0]) {
+              --world;
+              offsetX = worldWidth * world;
+              transforms.push(this.getRenderTransform(center, resolution, rotation, 0.5, width, height, offsetX).slice());
+              startX += worldWidth;
+            }
+            world = 0;
+            startX = extent[2];
+            while (startX > projectionExtent[2]) {
+              ++world;
+              offsetX = worldWidth * world;
+              transforms.push(this.getRenderTransform(center, resolution, rotation, 0.5, width, height, offsetX).slice());
+              startX -= worldWidth;
+            }
+          }
+
+          this.hitDetectionImageData_ = createHitDetectionImageData(size, transforms,
+            this.renderedFeatures_, layer.getStyleFunction(), extent, resolution, rotation);
+          resolve(hitDetect(pixel, this.renderedFeatures_, this.hitDetectionImageData_));
+        }.bind(this));
+      } else {
+        resolve(hitDetect(pixel, this.renderedFeatures_, this.hitDetectionImageData_));
+      }
+    }.bind(this));
+  }
+
   /**
    * @inheritDoc
    */
@@ -253,8 +340,10 @@ class CanvasVectorLayerRenderer extends CanvasLayerRenderer {
 
     if (!this.dirty_ && (!updateWhileAnimating && animating) ||
         (!updateWhileInteracting && interacting)) {
+      this.animatingOrInteracting_ = true;
       return true;
     }
+    this.animatingOrInteracting_ = false;
 
     const frameStateExtent = frameState.extent;
     const viewState = frameState.viewState;
@@ -269,6 +358,7 @@ class CanvasVectorLayerRenderer extends CanvasLayerRenderer {
       vectorLayerRenderOrder = defaultRenderOrder;
     }
 
+    const center = viewState.center.slice();
     const extent = buffer(frameStateExtent,
       vectorLayerRenderBuffer * resolution);
     const projectionExtent = viewState.projection.getExtent();
@@ -284,6 +374,8 @@ class CanvasVectorLayerRenderer extends CanvasLayerRenderer {
       const gutter = Math.max(getWidth(extent) / 2, worldWidth);
       extent[0] = projectionExtent[0] - gutter;
       extent[2] = projectionExtent[2] + gutter;
+      const worldsAway = Math.floor((center[0] - projectionExtent[0]) / worldWidth);
+      center[0] -= (worldsAway * worldWidth);
     }
 
     if (!this.dirty_ &&
@@ -334,23 +426,15 @@ class CanvasVectorLayerRenderer extends CanvasLayerRenderer {
     }.bind(this);
 
     const userExtent = toUserExtent(extent, projection);
+    /** @type {Array<import("../../Feature.js").default>} */
+    const features = vectorSource.getFeaturesInExtent(userExtent);
     if (vectorLayerRenderOrder) {
-      /** @type {Array<import("../../Feature.js").default>} */
-      const features = [];
-      vectorSource.forEachFeatureInExtent(userExtent,
-        /**
-         * @param {import("../../Feature.js").default} feature Feature.
-         */
-        function(feature) {
-          features.push(feature);
-        });
       features.sort(vectorLayerRenderOrder);
-      for (let i = 0, ii = features.length; i < ii; ++i) {
-        render(features[i]);
-      }
-    } else {
-      vectorSource.forEachFeatureInExtent(userExtent, render);
     }
+    for (let i = 0, ii = features.length; i < ii; ++i) {
+      render(features[i]);
+    }
+    this.renderedFeatures_ = features;
 
     const replayGroupInstructions = replayGroup.finish();
     const executorGroup = new ExecutorGroup(extent, resolution,
@@ -361,7 +445,11 @@ class CanvasVectorLayerRenderer extends CanvasLayerRenderer {
     this.renderedRevision_ = vectorLayerRevision;
     this.renderedRenderOrder_ = vectorLayerRenderOrder;
     this.renderedExtent_ = extent;
+    this.renderedRotation_ = viewState.rotation;
+    this.renderedCenter_ = center;
+    this.renderedProjection_ = projection;
     this.replayGroup_ = executorGroup;
+    this.hitDetectionImageData_ = null;
 
     this.replayGroupChanged = true;
     return true;

src/ol/renderer/canvas/VectorTileLayer.js

@@ -7,11 +7,12 @@ import TileState from '../../TileState.js';
 import ViewHint from '../../ViewHint.js';
 import {listen, unlistenByKey} from '../../events.js';
 import EventType from '../../events/EventType.js';
-import {buffer, containsCoordinate, equals, getIntersection, intersects} from '../../extent.js';
+import {buffer, containsCoordinate, equals, getIntersection, intersects, containsExtent, getWidth, getTopLeft} from '../../extent.js';
 import VectorTileRenderType from '../../layer/VectorTileRenderType.js';
 import ReplayType from '../../render/canvas/BuilderType.js';
 import CanvasBuilderGroup from '../../render/canvas/BuilderGroup.js';
 import CanvasTileLayerRenderer from './TileLayer.js';
+import {toSize} from '../../size.js';
 import {getSquaredTolerance as getSquaredRenderTolerance, renderFeature} from '../vector.js';
 import {
   apply as applyTransform,
@@ -25,6 +26,7 @@ import {
 } from '../../transform.js';
 import CanvasExecutorGroup, {replayDeclutter} from '../../render/canvas/ExecutorGroup.js';
 import {clear} from '../../obj.js';
+import {createHitDetectionImageData, hitDetect} from '../../render/canvas/hitdetect.js';
 
 
 /**
@@ -99,6 +101,18 @@ class CanvasVectorTileLayerRenderer extends CanvasTileLayerRenderer {
      */
     this.renderedLayerRevision_;
 
+    /**
+     * @private
+     * @type {import("../../transform").Transform}
+     */
+    this.renderedPixelToCoordinateTransform_ = null;
+
+    /**
+     * @private
+     * @type {number}
+     */
+    this.renderedRotation_;
+
     /**
      * @private
      * @type {!Object<string, import("../../VectorRenderTile.js").default>}
@@ -304,6 +318,7 @@ class CanvasVectorTileLayerRenderer extends CanvasTileLayerRenderer {
       if (renderOrder && renderOrder !== builderState.renderedRenderOrder) {
         features.sort(renderOrder);
       }
+      sourceTile.hitDetectionImageData = null;
       for (let i = 0, ii = features.length; i < ii; ++i) {
         const feature = features[i];
         if (!bufferedExtent || intersects(bufferedExtent, feature.getGeometry().getExtent())) {
@@ -380,6 +395,73 @@ class CanvasVectorTileLayerRenderer extends CanvasTileLayerRenderer {
     return found;
   }
 
+  /**
+   * @inheritDoc
+   */
+  getFeatures(pixel) {
+    return new Promise(function(resolve, reject) {
+      const layer = /** @type {import("../../layer/VectorTile.js").default} */ (this.getLayer());
+      const source = layer.getSource();
+      const projection = this.renderedProjection;
+      const projectionExtent = projection.getExtent();
+      const resolution = this.renderedResolution;
+      const pixelRatio = this.renderedPixelRatio;
+      const tileGrid = source.getTileGridForProjection(projection);
+      const sourceTileGrid = source.getTileGrid();
+      const coordinate = applyTransform(this.renderedPixelToCoordinateTransform_, pixel.slice());
+      const tileCoord = tileGrid.getTileCoordForCoordAndResolution(coordinate, resolution);
+      let sourceTile;
+      for (let i = 0, ii = this.renderedTiles.length; i < ii; ++i) {
+        if (tileCoord.toString() === this.renderedTiles[i].tileCoord.toString()) {
+          const tile = this.renderedTiles[i];
+          if (tile.getState() === TileState.LOADED && tile.hifi) {
+            const extent = tileGrid.getTileCoordExtent(tileCoord);
+            if (source.getWrapX() && projection.canWrapX() && !containsExtent(projectionExtent, extent)) {
+              const worldWidth = getWidth(projectionExtent);
+              const worldsAway = Math.floor((coordinate[0] - projectionExtent[0]) / worldWidth);
+              coordinate[0] -= (worldsAway * worldWidth);
+            }
+            const sourceTiles = source.getSourceTiles(pixelRatio, projection, tile);
+            const sourceTileCoord = sourceTileGrid.getTileCoordForCoordAndResolution(coordinate, resolution);
+            for (let j = 0, jj = sourceTiles.length; j < jj; ++j) {
+              if (sourceTileCoord.toString() === sourceTiles[j].tileCoord.toString()) {
+                sourceTile = sourceTiles[j];
+                break;
+              }
+            }
+          }
+          break;
+        }
+      }
+      if (!sourceTile) {
+        resolve([]);
+        return;
+      }
+      const corner = getTopLeft(tileGrid.getTileCoordExtent(sourceTile.tileCoord));
+      const tilePixel = [
+        (coordinate[0] - corner[0]) / resolution,
+        (corner[1] - coordinate[1]) / resolution
+      ];
+      if (!sourceTile.hitDetectionImageData) {
+        const tileSize = toSize(sourceTileGrid.getTileSize(sourceTileGrid.getZForResolution(resolution)));
+        const size = [tileSize[0] / 2, tileSize[1] / 2];
+        const rotation = this.renderedRotation_;
+        const transforms = [
+          this.getRenderTransform(tileGrid.getTileCoordCenter(sourceTile.tileCoord),
+            resolution, 0, 0.5, size[0], size[1], 0)
+        ];
+        requestAnimationFrame(function() {
+          sourceTile.hitDetectionImageData = createHitDetectionImageData(tileSize, transforms,
+            sourceTile.getFeatures(), layer.getStyleFunction(),
+            tileGrid.getTileCoordExtent(sourceTile.tileCoord), resolution, rotation);
+          resolve(hitDetect(tilePixel, sourceTile.getFeatures(), sourceTile.hitDetectionImageData));
+        });
+      } else {
+        resolve(hitDetect(tilePixel, sourceTile.getFeatures(), sourceTile.hitDetectionImageData));
+      }
+    }.bind(this));
+  }
+
   /**
    * @inheritDoc
    */
@@ -409,6 +491,9 @@ class CanvasVectorTileLayerRenderer extends CanvasTileLayerRenderer {
     this.renderQueuedTileImages_(hifi, frameState);
 
     super.renderFrame(frameState, target);
+    this.renderedPixelToCoordinateTransform_ = frameState.pixelToCoordinateTransform.slice();
+    this.renderedRotation_ = frameState.viewState.rotation;
+
 
     const layer = /** @type {import("../../layer/VectorTile.js").default} */ (this.getLayer());
     const renderMode = layer.getRenderMode();
@@ -429,7 +514,10 @@ class CanvasVectorTileLayerRenderer extends CanvasTileLayerRenderer {
     const declutterReplays = layer.getDeclutter() ? {} : null;
     const replayTypes = VECTOR_REPLAYS[renderMode];
     const pixelRatio = frameState.pixelRatio;
-    const rotation = frameState.viewState.rotation;
+    const viewState = frameState.viewState;
+    const center = viewState.center;
+    const resolution = viewState.resolution;
+    const rotation = viewState.rotation;
     const size = frameState.size;
 
     // set forward and inverse pixel transforms
@@ -463,7 +551,7 @@ class CanvasVectorTileLayerRenderer extends CanvasTileLayerRenderer {
       const tileCoord = tile.tileCoord;
       const tileExtent = tileGrid.getTileCoordExtent(tile.wrappedTileCoord);
       const worldOffset = tileGrid.getTileCoordExtent(tileCoord, this.tmpExtent)[0] - tileExtent[0];
-      const transform = this.getRenderTransform(frameState, width, height, worldOffset);
+      const transform = this.getRenderTransform(center, resolution, rotation, pixelRatio, width, height, worldOffset);
       const executorGroups = tile.executorGroups[getUid(layer)];
       let clipped = false;
       for (let t = 0, tt = executorGroups.length; t < tt; ++t) {

src/ol/source/Vector.js

@@ -675,14 +675,21 @@ class VectorSource extends Source {
    * all features intersecting the given extent in random order (so it may include
    * features whose geometries do not intersect the extent).
    *
-   * This method is not available when the source is configured with
-   * `useSpatialIndex` set to `false`.
+   * When `useSpatialIndex` is set to false, this method will return all
+   * features.
+   *
    * @param {import("../extent.js").Extent} extent Extent.
    * @return {Array<import("../Feature.js").default<Geometry>>} Features.
    * @api
    */
   getFeaturesInExtent(extent) {
-    return this.featuresRtree_.getInExtent(extent);
+    if (this.featuresRtree_) {
+      return this.featuresRtree_.getInExtent(extent);
+    } else if (this.featuresCollection_) {
+      return this.featuresCollection_.getArray();
+    } else {
+      return [];
+    }
   }
 
 

test/spec/ol/layer/vector.test.js

@@ -2,6 +2,10 @@ import Layer from '../../../../src/ol/layer/Layer.js';
 import VectorLayer from '../../../../src/ol/layer/Vector.js';
 import VectorSource from '../../../../src/ol/source/Vector.js';
 import Style, {createDefaultStyle} from '../../../../src/ol/style/Style.js';
+import Feature from '../../../../src/ol/Feature.js';
+import Point from '../../../../src/ol/geom/Point.js';
+import Map from '../../../../src/ol/Map.js';
+import View from '../../../../src/ol/View.js';
 
 
 describe('ol.layer.Vector', function() {
@@ -123,4 +127,55 @@ describe('ol.layer.Vector', function() {
 
   });
 
+  describe('#getFeatures()', function() {
+
+    let map, layer;
+
+    beforeEach(function() {
+      layer = new VectorLayer({
+        source: new VectorSource({
+          features: [
+            new Feature({
+              geometry: new Point([-1000000, 0]),
+              name: 'feature1'
+            }),
+            new Feature({
+              geometry: new Point([1000000, 0]),
+              name: 'feture2'
+            })
+          ]
+        })
+      });
+      const container = document.createElement('div');
+      container.style.width = '256px';
+      container.style.height = '256px';
+      document.body.appendChild(container);
+      map = new Map({
+        target: container,
+        layers: [
+          layer
+        ],
+        view: new View({
+          zoom: 2,
+          center: [0, 0]
+        })
+      });
+    });
+
+    afterEach(function() {
+      document.body.removeChild(map.getTargetElement());
+      map.setTarget(null);
+    });
+
+    it('detects features properly', function(done) {
+      map.renderSync();
+      const pixel = map.getPixelFromCoordinate([-1000000, 0]);
+      layer.getFeatures(pixel).then(function(features) {
+        expect(features[0].get('name')).to.be('feature1');
+        done();
+      });
+    });
+
+  });
+
 });

test/spec/ol/layer/vectortile.test.js

@@ -1,5 +1,9 @@
 import VectorTileLayer from '../../../../src/ol/layer/VectorTile.js';
 import VectorTileSource from '../../../../src/ol/source/VectorTile.js';
+import GeoJSON from '../../../../src/ol/format/GeoJSON.js';
+import View from '../../../../src/ol/View.js';
+import Map from '../../../../src/ol/Map.js';
+import {fromLonLat} from '../../../../src/ol/proj.js';
 
 
 describe('ol.layer.VectorTile', function() {
@@ -57,4 +61,74 @@ describe('ol.layer.VectorTile', function() {
     });
   });
 
+  describe('#getFeatures()', function() {
+
+    let map, layer;
+
+    beforeEach(function() {
+      layer = new VectorTileLayer({
+        source: new VectorTileSource({
+          format: new GeoJSON(),
+          url: `data:application/json;charset=utf-8,
+            {
+              "type": "FeatureCollection",
+              "features": [
+                {
+                  "type": "Feature",
+                  "geometry": {
+                    "type": "Point",
+                    "coordinates": [-36, 0]
+                  },
+                  "properties": {
+                    "name": "feature1"
+                  }
+                },
+                {
+                  "type": "Feature",
+                  "geometry": {
+                    "type": "Point",
+                    "coordinates": [36, 0]
+                  },
+                  "properties": {
+                    "name": "feature2"
+                  }
+                }
+              ]
+            }
+          `
+        })
+      });
+      const container = document.createElement('div');
+      container.style.width = '256px';
+      container.style.height = '256px';
+      document.body.appendChild(container);
+      map = new Map({
+        target: container,
+        layers: [
+          layer
+        ],
+        view: new View({
+          zoom: 0,
+          center: [0, 0]
+        })
+      });
+    });
+
+    afterEach(function() {
+      document.body.removeChild(map.getTargetElement());
+      map.setTarget(null);
+    });
+
+    it('detects features properly', function(done) {
+      map.once('rendercomplete', function() {
+        const pixel = map.getPixelFromCoordinate(fromLonLat([-36, 0]));
+        layer.getFeatures(pixel).then(function(features) {
+          expect(features[0].get('name')).to.be('feature1');
+          done();
+        });
+      });
+    });
+
+  });
+
 });

test/spec/ol/renderer/canvas/vectorimage.test.js

@@ -40,6 +40,7 @@ describe('ol/renderer/canvas/VectorImageLayer', function() {
         extent: extent,
         viewHints: [],
         viewState: {
+          center: [0, 0],
           projection: projection,
           resolution: 1,
           rotation: 0

test/spec/ol/renderer/canvas/vectorlayer.test.js

@@ -208,6 +208,7 @@ describe('ol.renderer.canvas.VectorLayer', function() {
       const frameState = {
         layerStatesArray: [{}],
         viewState: {
+          center: [0, 0],
           resolution: 1,
           rotation: 0
         }
@@ -234,6 +235,7 @@ describe('ol.renderer.canvas.VectorLayer', function() {
       frameState = {
         viewHints: [],
         viewState: {
+          center: [0, 0],
           projection: projection,
           resolution: 1,
           rotation: 0

test/spec/ol/renderer/canvas/vectortilelayer.test.js

@@ -22,6 +22,7 @@ import VectorTileRenderType from '../../../../../src/ol/layer/VectorTileRenderTy
 import {getUid} from '../../../../../src/ol/util.js';
 import TileLayer from '../../../../../src/ol/layer/Tile.js';
 import XYZ from '../../../../../src/ol/source/XYZ.js';
+import {create} from '../../../../../src/ol/transform.js';
 
 
 describe('ol.renderer.canvas.VectorTileLayer', function() {
@@ -262,6 +263,7 @@ describe('ol.renderer.canvas.VectorTileLayer', function() {
         layerIndex: 0,
         extent: proj.getExtent(),
         pixelRatio: 1,
+        pixelToCoordinateTransform: create(),
         time: Date.now(),
         viewHints: [],
         viewState: {