SAMPLE_SHADERS = () => ({
  builder: new ShaderBuilder()
    .setFillColorExpression('vec4(1.0)')
    .setStrokeColorExpression('vec4(1.0)')
    .setSymbolColorExpression('vec4(1.0)'),
  attributes: {
    prop_attr1: {
      callback: (feature) => feature.get('test'),
    },
    prop_attr2: {callback: () => [10, 20, 30], size: 3},
  },
  uniforms: {
    custom: () => 1234,
  },
})
@type {import('../../../../../../src/ol/render/webgl/VectorStyleRenderer.js').AsShaders}