Docs/Add sample for centered point labels

docs/.vuepress/config.js

@@ -164,6 +164,7 @@ module.exports = {
             'other-charts/pie',
             'other-charts/multi-series-pie',
             'other-charts/polar-area',
+            'other-charts/polar-area-center-labels',
             'other-charts/radar',
             'other-charts/radar-skip-points',
             'other-charts/combo-bar-line',

docs/samples/other-charts/polar-area-center-labels.md

@@ -0,0 +1,102 @@
+# Polar area centered point labels
+
+```js chart-editor
+// <block:actions:2>
+const actions = [
+  {
+    name: 'Randomize',
+    handler(chart) {
+      chart.data.datasets.forEach(dataset => {
+        dataset.data = Utils.numbers({count: chart.data.labels.length, min: 0, max: 100});
+      });
+      chart.update();
+    }
+  },
+  {
+    name: 'Add Data',
+    handler(chart) {
+      const data = chart.data;
+      if (data.datasets.length > 0) {
+        data.labels.push('data #' + (data.labels.length + 1));
+
+        for (let index = 0; index < data.datasets.length; ++index) {
+          data.datasets[index].data.push(Utils.rand(0, 100));
+        }
+
+        chart.update();
+      }
+    }
+  },
+  {
+    name: 'Remove Data',
+    handler(chart) {
+      chart.data.labels.splice(-1, 1); // remove the label first
+
+      chart.data.datasets.forEach(dataset => {
+        dataset.data.pop();
+      });
+
+      chart.update();
+    }
+  }
+];
+// </block:actions>
+
+// <block:setup:1>
+const DATA_COUNT = 5;
+const NUMBER_CFG = {count: DATA_COUNT, min: 0, max: 100};
+
+const labels = ['Red', 'Orange', 'Yellow', 'Green', 'Blue'];
+const data = {
+  labels: labels,
+  datasets: [
+    {
+      label: 'Dataset 1',
+      data: Utils.numbers(NUMBER_CFG),
+      backgroundColor: [
+        Utils.transparentize(Utils.CHART_COLORS.red, 0.5),
+        Utils.transparentize(Utils.CHART_COLORS.orange, 0.5),
+        Utils.transparentize(Utils.CHART_COLORS.yellow, 0.5),
+        Utils.transparentize(Utils.CHART_COLORS.green, 0.5),
+        Utils.transparentize(Utils.CHART_COLORS.blue, 0.5),
+      ]
+    }
+  ]
+};
+// </block:setup>
+
+// <block:config:0>
+const config = {
+  type: 'polarArea',
+  data: data,
+  options: {
+    responsive: true,
+    scales: {
+      r: {
+        pointLabels: {
+          display: true,
+          centerPointLabels: true,
+          font: {
+            size: 18
+          }
+        }
+      }
+    },
+    plugins: {
+      legend: {
+        position: 'top',
+      },
+      title: {
+        display: true,
+        text: 'Chart.js Polar Area Chart With Centered Point Labels'
+      }
+    }
+  },
+};
+// </block:config>
+
+module.exports = {
+  actions: actions,
+  config: config,
+};
+```