openlayers/test/spec/ol/render/canvas/textbuilder.test.js

import Circle from '../../../../../src/ol/geom/Circle.js';
import Executor from '../../../../../src/ol/render/canvas/Executor.js';
import Feature from '../../../../../src/ol/Feature.js';
import LineString from '../../../../../src/ol/geom/LineString.js';
import MultiLineString from '../../../../../src/ol/geom/MultiLineString.js';
import MultiPoint from '../../../../../src/ol/geom/MultiPoint.js';
import MultiPolygon from '../../../../../src/ol/geom/MultiPolygon.js';
import Point from '../../../../../src/ol/geom/Point.js';
import Polygon from '../../../../../src/ol/geom/Polygon.js';
import Text from '../../../../../src/ol/style/Text.js';
import TextBuilder from '../../../../../src/ol/render/canvas/TextBuilder.js';
import {create as createTransform} from '../../../../../src/ol/transform.js';

function createBuilder() {
  return new TextBuilder(1, [-180, -90, 180, 90], 0.02, 1, true);
}

function createContext() {
  return {
    fill: function () {},
    stroke: function () {},
    beginPath: function () {},
    clip: function () {},
    moveTo: function () {},
    lineTo: function () {},
    closePath: function () {},
    setLineDash: function () {},
    save: function () {},
    restore: function () {},
  };
}

function executeInstructions(
  builder,
  expectedDrawTextImageCalls,
  expectedBuilderImageCalls
) {
  const transform = createTransform();
  const context = createContext();
  const executor = new Executor(0.02, 1, false, builder.finish());
  sinon.spy(executor, 'drawLabelWithPointPlacement_');
  const replayImageOrLabelStub = sinon.stub(executor, 'replayImageOrLabel_');
  executor.execute(context, 1, transform);
  expect(executor.drawLabelWithPointPlacement_.callCount).to.be(
    expectedDrawTextImageCalls
  );
  expect(replayImageOrLabelStub.callCount).to.be(expectedBuilderImageCalls);
}

describe('ol.render.canvas.TextBuilder', function () {
  it('builds correct coordinates array with a stride of 2 for geometries with 2 dimensions', function () {
    const builder = createBuilder();
    const features = [
      new Feature(new Point([0, 0])),
      new Feature(new Point([1, 1])),
      new Feature(
        new MultiLineString([
          new LineString([
            [1, 1],
            [3, 3],
          ]),
          new LineString([
            [2, 2],
            [4, 4],
          ]),
        ])
      ),
      new Feature(
        new LineString([
          [3, 3],
          [5, 5],
        ])
      ),
      new Feature(new Circle([5, 5, 7], 4)),
      new Feature(
        new MultiPoint([
          [6, 6],
          [7, 7],
        ])
      ),
      new Feature(
        new Polygon([
          [
            [7, 7],
            [7, 9],
            [9, 9],
            [9, 7],
            [7, 7],
          ],
        ])
      ),
      new Feature(
        new MultiPolygon([
          new Polygon([
            [
              [8, 8],
              [8, 10],
              [10, 10],
              [10, 8],
              [8, 8],
            ],
          ]),
          new Polygon([
            [
              [9, 9],
              [9, 11],
              [11, 11],
              [11, 9],
              [9, 9],
            ],
          ]),
        ])
      ),
    ];
    builder.setTextStyle(
      new Text({
        text: 'Text',
      })
    );
    features.forEach(function (feature) {
      builder.drawText(feature.getGeometry(), feature);
    });
    expect(builder.coordinates).to.eql([
      0,
      0,
      1,
      1,
      2,
      2,
      3,
      3,
      4,
      4,
      5,
      5,
      6,
      6,
      7,
      7,
      8,
      8,
      9,
      9,
      10,
      10,
    ]);
  });

  it('builds correct coordinates array with a stride of 2 for geometries with 3 dimensions', function () {
    const builder = createBuilder();
    const features = [
      new Feature(new Point([0, 0, 1])),
      new Feature(new Point([1, 1, 2])),
      new Feature(
        new MultiLineString([
          new LineString([
            [1, 1, 1],
            [3, 3, 2],
          ]),
          new LineString([
            [2, 2, 3],
            [4, 4, 4],
          ]),
        ])
      ),
      new Feature(
        new LineString([
          [3, 3, 5],
          [5, 5, 6],
        ])
      ),
      new Feature(new Circle([5, 5, 7], 4)),
      new Feature(
        new MultiPoint([
          [6, 6, 8],
          [7, 7, 9],
        ])
      ),
      new Feature(
        new Polygon([
          [
            [7, 7, 1],
            [7, 9, 2],
            [9, 9, 3],
            [9, 7, 4],
            [7, 7, 5],
          ],
        ])
      ),
      new Feature(
        new MultiPolygon([
          new Polygon([
            [
              [8, 8, 1],
              [8, 10, 2],
              [10, 10, 3],
              [10, 8, 4],
              [8, 8, 1],
            ],
          ]),
          new Polygon([
            [
              [9, 9, 5],
              [9, 11, 6],
              [11, 11, 7],
              [11, 9, 8],
              [9, 9, 5],
            ],
          ]),
        ])
      ),
    ];
    builder.setTextStyle(
      new Text({
        text: 'Text',
      })
    );
    features.forEach(function (feature) {
      builder.drawText(feature.getGeometry(), feature);
    });
    expect(builder.coordinates).to.eql([
      0,
      0,
      1,
      1,
      2,
      2,
      3,
      3,
      4,
      4,
      5,
      5,
      6,
      6,
      7,
      7,
      8,
      8,
      9,
      9,
      10,
      10,
    ]);
  });

  it('renders polygon labels only when they fit', function () {
    let builder = createBuilder();
    const geometry = new Polygon([
      [
        [0, 0],
        [0, 1],
        [1, 1],
        [1, 0],
        [0, 0],
      ],
    ]);
    const feature = new Feature(geometry);

    builder.setTextStyle(
      new Text({
        text: 'This is a long text',
      })
    );
    builder.drawText(geometry, feature);
    expect(builder.instructions.length).to.be(3);
    executeInstructions(builder, 1, 0);

    builder = createBuilder();
    builder.setTextStyle(
      new Text({
        text: 'short',
      })
    );
    builder.drawText(geometry, feature);
    expect(builder.instructions.length).to.be(3);
    executeInstructions(builder, 1, 1);
  });

  it('renders multipolygon labels only when they fit', function () {
    const geometry = new MultiPolygon([
      [
        [
          [0, 0],
          [0, 1],
          [1, 1],
          [1, 0],
          [0, 0],
        ],
      ],
      [
        [
          [1, 1],
          [1, 2],
          [2, 2],
          [2, 1],
          [1, 1],
        ],
      ],
    ]);
    const feature = new Feature(geometry);

    let builder = createBuilder();
    builder.setTextStyle(
      new Text({
        text: 'This is a long text',
      })
    );
    builder.drawText(geometry, feature);
    expect(builder.instructions.length).to.be(3);
    executeInstructions(builder, 1, 0);

    builder = createBuilder();
    builder.setTextStyle(
      new Text({
        text: 'short',
      })
    );
    builder.drawText(geometry, feature);
    expect(builder.instructions.length).to.be(3);
    executeInstructions(builder, 1, 2);
  });

  it('generates a matching geometry widths array for multipolygons', function () {
    const feature = new Feature(
      new MultiPolygon([
        [
          [
            [-180, -90],
            [-180, 90],
            [-50, 90],
            [-50, -90],
            [-180, -90],
          ],
        ],
        [
          [
            [-50, -90],
            [-50, 90],
            [70, 90],
            [70, -90],
            [-50, -90],
          ],
        ],
        [
          [
            [70, -90],
            [70, 90],
            [180, 90],
            [180, -90],
            [70, -90],
          ],
        ],
      ])
    );
    const builder = new TextBuilder(1, [-50, -90, 70, 90], 1, 1);
    builder.setTextStyle(
      new Text({
        text: 'text',
      })
    );
    builder.drawText(feature.getGeometry(), feature);
    expect(builder.coordinates).to.have.length(2);
    expect(builder.instructions).to.have.length(3);
    const geometryWidths = builder.instructions[1][24];
    expect(geometryWidths).to.have.length(1);
    expect(geometryWidths[0]).to.be(120);
  });
});