docs: Add a test for hardware picking with many cells

Sources/Rendering/Core/HardwareSelector/test/testHardwareSelectorManyCells.js

@@ -0,0 +1,83 @@
+import test from 'tape';
+import testUtils from 'vtk.js/Sources/Testing/testUtils';
+
+import 'vtk.js/Sources/Rendering/OpenGL/RenderWindow';
+import 'vtk.js/Sources/Rendering/OpenGL/Camera';
+import 'vtk.js/Sources/Rendering/OpenGL/Renderer';
+import 'vtk.js/Sources/Rendering/OpenGL/Actor';
+import 'vtk.js/Sources/Rendering/OpenGL/PolyDataMapper';
+
+import vtkRenderWindow from 'vtk.js/Sources/Rendering/Core/RenderWindow';
+import vtkRenderer from 'vtk.js/Sources/Rendering/Core/Renderer';
+import vtkActor from 'vtk.js/Sources/Rendering/Core/Actor';
+import vtkMapper from 'vtk.js/Sources/Rendering/Core/Mapper';
+import vtkPolyData from 'vtk.js/Sources/Common/DataModel/PolyData';
+import { FieldAssociations } from 'vtk.js/Sources/Common/DataModel/DataSet/Constants';
+
+test('Test HardwareSelector', (tapeContext) => {
+  const gc = testUtils.createGarbageCollector(tapeContext);
+  tapeContext.ok('rendering', 'vtkHardwareSelector TestHardwareSelector');
+
+  // Create some control UI
+  const container = document.querySelector('body');
+  const renderWindowContainer = gc.registerDOMElement(
+    document.createElement('div')
+  );
+  container.appendChild(renderWindowContainer);
+
+  // Create a polydata with many cells to force high24 pass
+  // 17 million vert cells and one poly cell (a triangle)
+  const bigPolydata = gc.registerResource(vtkPolyData.newInstance());
+  const numberOfVerts = 17_000_000;
+  // Points of the triangle
+  const pointsData = Float32Array.from([
+    ...[0, 0, 0],
+    ...[1, 0, 0], // This point will be also for verts
+    ...[0.5, 0.7, 0],
+  ]);
+  bigPolydata.getPoints().setData(pointsData, 3);
+  // The triangle cell
+  const polysData = Uint32Array.from([3, 0, 1, 2]);
+  bigPolydata.getPolys().setData(polysData, 1);
+  // The vert cells, all using the point of index 1
+  const vertsData = new Uint32Array(2 * numberOfVerts);
+  vertsData.fill(1);
+  bigPolydata.getVerts().setData(vertsData, 1);
+
+  // Setup the rest of the rendering pipeline, from mapper to OpenGL render window
+  const mapper = gc.registerResource(vtkMapper.newInstance());
+  mapper.setInputData(bigPolydata);
+
+  const actor = gc.registerResource(vtkActor.newInstance());
+  actor.setMapper(mapper);
+
+  const renderer = gc.registerResource(vtkRenderer.newInstance());
+  renderer.setBackground(0.32, 0.34, 0.43);
+  renderer.addActor(actor);
+
+  const renderWindow = gc.registerResource(vtkRenderWindow.newInstance());
+  renderWindow.addRenderer(renderer);
+
+  const glwindow = gc.registerResource(renderWindow.newAPISpecificView());
+  glwindow.setContainer(renderWindowContainer);
+  glwindow.setSize(400, 400);
+  renderWindow.addView(glwindow);
+
+  // Render to make set up the rendering pipeline
+  renderWindow.render();
+
+  // Selector
+  const selector = glwindow.getSelector();
+  selector.setFieldAssociation(FieldAssociations.FIELD_ASSOCIATION_CELLS);
+  selector.setCaptureZValues(false);
+  selector.attach(glwindow, renderer);
+  selector.setArea(200, 200, 200, 200);
+
+  const bufferCaptured = selector.captureBuffers();
+  tapeContext.ok(bufferCaptured, 'Selector captured buffer');
+
+  const info = selector.getPixelInformation([200, 200], 0, [0, 0]);
+  tapeContext.equal(info?.attributeID, numberOfVerts, 'Last triangle picked');
+
+  gc.releaseResources();
+});