From 8722acb9dc0a93d12f64ba41ed11524331304e2b Mon Sep 17 00:00:00 2001
From: "arnaud.morvan@camptocamp.com" <arnaud.morvan@camptocamp.com>
Date: Wed, 15 Jan 2020 10:35:50 +0100
Subject: [PATCH] Add cache for styles in getStyleFunction

---
 c2cgeoform/static/src/styles.js | 48 ++++++++++++++++++---------------
 1 file changed, 26 insertions(+), 22 deletions(-)

diff --git a/c2cgeoform/static/src/styles.js b/c2cgeoform/static/src/styles.js
index 81c45ad0..cfa9d55f 100644
--- a/c2cgeoform/static/src/styles.js
+++ b/c2cgeoform/static/src/styles.js
@@ -3,41 +3,45 @@ import { Circle, Fill, Stroke, Style, Icon } from 'ol/style.js'
 const defaultIconUrl =
   'data:image/png;base64,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'
 
-export function getDefaultStyle() {
-  return new Style({
+export const defaultStyle = new Style({
+  stroke: new Stroke({
+    color: 'blue',
+    width: 3,
+  }),
+  fill: new Fill({
+    color: 'rgba(0, 0, 255, 0.1)',
+  }),
+  image: new Circle({
+    radius: 6,
     stroke: new Stroke({
-      color: 'blue',
-      width: 3,
+      width: 1.5,
+      color: 'rgba(0, 0, 255, 1)',
     }),
     fill: new Fill({
-      color: 'rgba(0, 0, 255, 0.1)',
+      color: 'rgba(0, 0, 255, 0.4)',
     }),
-    image: new Circle({
-      radius: 6,
-      stroke: new Stroke({
-        width: 1.5,
-        color: 'rgba(0, 0, 255, 1)',
-      }),
-      fill: new Fill({
-        color: 'rgba(0, 0, 255, 0.4)',
-      }),
-    }),
-  })
-}
+  }),
+})
 
 export function getStyleFunction(options) {
+  const cache = {}
   return feature => {
     if (feature.getGeometry().getType() == 'Point') {
-      return new Style({
+      return defaultStyle
+    }
+    const src = feature.get('icon') || options.icon || defaultIconUrl
+    const opacity = feature == options.context?.feature ? 1 : options.opacity
+    const key = `${src}:${opacity}`
+    if (cache[key] === undefined) {
+      cache[key] = new Style({
         image: new Icon({
           anchorXUnits: 'fraction',
           anchorYUnits: 'pixels',
-          src: feature.get('icon') || options.icon || defaultIconUrl,
-          opacity: feature == options.context?.feature ? 1 : options.opacity,
+          src: src,
+          opacity: opacity,
         }),
       })
-    } else {
-      return getDefaultStyle()
     }
+    return cache[key]
   }
 }