Merge pull request #1381 from twpayne/vector-api-feature-style-function

[vector-api] Per-feature styleFunction

src/ol/feature.js

@@ -5,16 +5,24 @@ goog.require('goog.events');
 goog.require('goog.events.EventType');
 goog.require('ol.Object');
 goog.require('ol.geom.Geometry');
+goog.require('ol.style.Style');
 
 
 /**
  * @enum {string}
  */
 ol.FeatureProperty = {
-  GEOMETRY: 'geometry'
+  GEOMETRY: 'geometry',
+  STYLE_FUNCTION: 'styleFunction'
 };
 
 
+/**
+ * @typedef {function(this: ol.Feature, number): Array.<ol.style.Style>}
+ */
+ol.FeatureStyleFunction;
+
+
 
 /**
  * @constructor
@@ -47,6 +55,9 @@ ol.Feature = function(opt_geometryOrValues) {
   goog.events.listen(
       this, ol.Object.getChangeEventType(ol.FeatureProperty.GEOMETRY),
       this.handleGeometryChanged_, false, this);
+  goog.events.listen(
+      this, ol.Object.getChangeEventType(ol.FeatureProperty.STYLE_FUNCTION),
+      this.handleStyleFunctionChange_, false, this);
 
   if (goog.isDefAndNotNull(opt_geometryOrValues)) {
     if (opt_geometryOrValues instanceof ol.geom.Geometry) {
@@ -102,6 +113,19 @@ ol.Feature.prototype.getRevision = function() {
 };
 
 
+/**
+ * @return {ol.FeatureStyleFunction|undefined} Style function.
+ */
+ol.Feature.prototype.getStyleFunction = function() {
+  return /** @type {ol.FeatureStyleFunction|undefined} */ (
+      this.get(ol.FeatureProperty.STYLE_FUNCTION));
+};
+goog.exportProperty(
+    ol.Feature.prototype,
+    'getStyleFunction',
+    ol.Feature.prototype.getStyleFunction);
+
+
 /**
  * @private
  */
@@ -127,6 +151,14 @@ ol.Feature.prototype.handleGeometryChanged_ = function() {
 };
 
 
+/**
+ * @private
+ */
+ol.Feature.prototype.handleStyleFunctionChange_ = function() {
+  this.dispatchChangeEvent();
+};
+
+
 /**
  * @param {ol.geom.Geometry|undefined} geometry Geometry.
  */
@@ -139,6 +171,18 @@ goog.exportProperty(
     ol.Feature.prototype.setGeometry);
 
 
+/**
+ * @param {ol.FeatureStyleFunction|undefined} styleFunction Style function.
+ */
+ol.Feature.prototype.setStyleFunction = function(styleFunction) {
+  this.set(ol.FeatureProperty.STYLE_FUNCTION, styleFunction);
+};
+goog.exportProperty(
+    ol.Feature.prototype,
+    'setStyleFunction',
+    ol.Feature.prototype.setStyleFunction);
+
+
 /**
  * @param {number|string|undefined} id Id.
  */

src/ol/layer/vectorlayer.js

@@ -35,6 +35,21 @@ ol.layer.Vector = function(opt_options) {
 goog.inherits(ol.layer.Vector, ol.layer.Layer);
 
 
+/**
+ * @param {ol.Feature} feature Feature.
+ * @param {number} resolution Resolution.
+ * @return {Array.<ol.style.Style>} Styles.
+ */
+ol.layer.Vector.defaultStyleFunction = function(feature, resolution) {
+  var featureStyleFunction = feature.getStyleFunction();
+  if (goog.isDef(featureStyleFunction)) {
+    return featureStyleFunction.call(feature, resolution);
+  } else {
+    return null;
+  }
+};
+
+
 /**
  * @return {function(ol.geom.Geometry): boolean|undefined} Render geometry
  *     function.

src/ol/renderer/canvas/canvasvectorlayerrenderer.js

@@ -6,6 +6,7 @@ goog.require('goog.events.EventType');
 goog.require('goog.functions');
 goog.require('ol.ViewHint');
 goog.require('ol.extent');
+goog.require('ol.layer.Vector');
 goog.require('ol.render.canvas.ReplayGroup');
 goog.require('ol.renderer.canvas.Layer');
 goog.require('ol.renderer.vector');
@@ -194,6 +195,9 @@ ol.renderer.canvas.VectorLayer.prototype.prepareFrame =
   this.dirty_ = false;
 
   var styleFunction = vectorLayer.getStyleFunction();
+  if (!goog.isDef(styleFunction)) {
+    styleFunction = ol.layer.Vector.defaultStyleFunction;
+  }
   var replayGroup = new ol.render.canvas.ReplayGroup();
   vectorSource.forEachFeatureInExtent(extent,
       /**
@@ -227,6 +231,10 @@ ol.renderer.canvas.VectorLayer.prototype.renderFeature =
     function(feature, resolution, styleFunction, replayGroup) {
   var loading = false;
   var styles = styleFunction(feature, resolution);
+  // FIXME if styles is null, should we use the default style?
+  if (!goog.isDefAndNotNull(styles)) {
+    return false;
+  }
   // simplify to a tolerance of half a CSS pixel
   var squaredTolerance = resolution * resolution / 4;
   var i, ii, style, imageStyle, imageState;

src/ol/style/fillstyle.js

@@ -6,9 +6,11 @@ goog.require('ol.color');
 
 /**
  * @constructor
- * @param {olx.style.FillOptions} options Options.
+ * @param {olx.style.FillOptions=} opt_options Options.
  */
-ol.style.Fill = function(options) {
+ol.style.Fill = function(opt_options) {
+
+  var options = goog.isDef(opt_options) ? opt_options : {};
 
   /**
    * @type {ol.Color|string}

src/ol/style/imagestyle.js

@@ -24,10 +24,12 @@ ol.style.ImageState = {
 
 /**
  * @constructor
- * @param {olx.style.ImageOptions} options Options.
+ * @param {olx.style.ImageOptions=} opt_options Options.
  * @extends {goog.events.EventTarget}
  */
-ol.style.Image = function(options) {
+ol.style.Image = function(opt_options) {
+
+  var options = goog.isDef(opt_options) ? opt_options : {};
 
   goog.base(this);
 

src/ol/style/strokestyle.js

@@ -6,9 +6,11 @@ goog.require('ol.color');
 
 /**
  * @constructor
- * @param {olx.style.StrokeOptions} options Options.
+ * @param {olx.style.StrokeOptions=} opt_options Options.
  */
-ol.style.Stroke = function(options) {
+ol.style.Stroke = function(opt_options) {
+
+  var options = goog.isDef(opt_options) ? opt_options : {};
 
   /**
    * @type {ol.Color|string}

src/ol/style/style.js

@@ -8,10 +8,12 @@ goog.require('ol.style.Image');
 
 /**
  * @constructor
- * @param {olx.style.StyleOptions} options Style options.
+ * @param {olx.style.StyleOptions=} opt_options Style options.
  * @todo stability experimental
  */
-ol.style.Style = function(options) {
+ol.style.Style = function(opt_options) {
+
+  var options = goog.isDef(opt_options) ? opt_options : {};
 
   /**
    * @type {ol.style.Fill}

src/ol/style/textstyle.js

@@ -4,9 +4,11 @@ goog.provide('ol.style.Text');
 
 /**
  * @constructor
- * @param {olx.style.TextOptions} options Options.
+ * @param {olx.style.TextOptions=} opt_options Options.
  */
-ol.style.Text = function(options) {
+ol.style.Text = function(opt_options) {
+
+  var options = goog.isDef(opt_options) ? opt_options : {};
 
   /**
    * @type {string|undefined}