From a2d83f5358936096d82e5d4e4d66923a47484395 Mon Sep 17 00:00:00 2001
From: Olivier Guyot <olivier.guyot@camptocamp.com>
Date: Tue, 14 May 2019 10:42:54 +0200
Subject: [PATCH] WebGL points / add minimal tests

---
 .../ol/renderer/webgl/pointslayer.test.js     | 108 ++++++++++++++++++
 1 file changed, 108 insertions(+)
 create mode 100644 test/spec/ol/renderer/webgl/pointslayer.test.js

diff --git a/test/spec/ol/renderer/webgl/pointslayer.test.js b/test/spec/ol/renderer/webgl/pointslayer.test.js
new file mode 100644
index 0000000000..4afa629605
--- /dev/null
+++ b/test/spec/ol/renderer/webgl/pointslayer.test.js
@@ -0,0 +1,108 @@
+import Feature from '../../../../../src/ol/Feature.js';
+import Point from '../../../../../src/ol/geom/Point.js';
+import LineString from '../../../../../src/ol/geom/LineString.js';
+import VectorLayer from '../../../../../src/ol/layer/Vector.js';
+import VectorSource from '../../../../../src/ol/source/Vector.js';
+import WebGLPointsLayerRenderer from '../../../../../src/ol/renderer/webgl/PointsLayer';
+import {get as getProjection} from '../../../../../src/ol/proj';
+import Polygon from '../../../../../src/ol/geom/Polygon';
+
+
+describe('ol.renderer.webgl.PointsLayer', function() {
+
+  describe('constructor', function() {
+
+    let target;
+
+    beforeEach(function () {
+      target = document.createElement('div');
+      target.style.width = '256px';
+      target.style.height = '256px';
+      document.body.appendChild(target);
+    });
+
+    afterEach(function () {
+      document.body.removeChild(target);
+    });
+
+    it('creates a new instance', function () {
+      const layer = new VectorLayer({
+        source: new VectorSource()
+      });
+      const renderer = new WebGLPointsLayerRenderer(layer);
+      expect(renderer).to.be.a(WebGLPointsLayerRenderer);
+    });
+
+  });
+
+  describe('#prepareFrame', function() {
+    let layer, renderer, frameState;
+
+    beforeEach(function() {
+      layer = new VectorLayer({
+        source: new VectorSource()
+      });
+      renderer = new WebGLPointsLayerRenderer(layer);
+      const projection = getProjection('EPSG:3857');
+      frameState = {
+        skippedFeatureUids: {},
+        viewHints: [],
+        viewState: {
+          projection: projection,
+          resolution: 1,
+          rotation: 0,
+          center: [10, 10]
+        },
+        size: [256, 256]
+      };
+    });
+
+    it('calls WebGlHelper#prepareDraw', function() {
+      const spy = sinon.spy(renderer.helper_, 'prepareDraw');
+      renderer.prepareFrame(frameState);
+      expect(spy.called).to.be(true);
+    });
+
+    it('fills up a buffer with 2 triangles per point', function() {
+      layer.getSource().addFeature(new Feature({
+        geometry: new Point([10, 20])
+      }));
+      renderer.prepareFrame(frameState);
+
+      const attributePerVertex = 12;
+      expect(renderer.verticesBuffer_.getArray().length).to.eql(4 * attributePerVertex);
+      expect(renderer.indicesBuffer_.getArray().length).to.eql(6);
+    });
+
+    it('ignores geometries other than points', function() {
+      layer.getSource().addFeature(new Feature({
+        geometry: new LineString([[10, 20], [30, 20]])
+      }));
+      layer.getSource().addFeature(new Feature({
+        geometry: new Polygon([[10, 20], [30, 20], [30, 10], [10, 20]])
+      }));
+      renderer.prepareFrame(frameState);
+
+      expect(renderer.verticesBuffer_.getArray().length).to.eql(0);
+      expect(renderer.indicesBuffer_.getArray().length).to.eql(0);
+    });
+
+    it('clears the buffers when the features are gone', function() {
+      const source = layer.getSource();
+      source.addFeature(new Feature({
+        geometry: new Point([10, 20])
+      }));
+      source.removeFeature(source.getFeatures()[0]);
+      source.addFeature(new Feature({
+        geometry: new Point([10, 20])
+      }));
+      renderer.prepareFrame(frameState);
+
+      const attributePerVertex = 12;
+      expect(renderer.verticesBuffer_.getArray().length).to.eql(4 * attributePerVertex);
+      expect(renderer.indicesBuffer_.getArray().length).to.eql(6);
+    });
+
+  });
+
+});