vega-lite/src/compile/mark/line.ts

Vega-Lite is a concise high-level language for interactive visualization.

import {UnitModel} from '../unit.js';
import {MarkCompiler} from './base.js';
import * as encode from './encode/index.js';

export const line: MarkCompiler = {
  vgMark: 'line',
  encodeEntry: (model: UnitModel) => {
    return {
      ...encode.baseEncodeEntry(model, {
        align: 'ignore',
        baseline: 'ignore',
        color: 'include',
        size: 'ignore',
        orient: 'ignore',
        theta: 'ignore',
      }),
      ...encode.pointPosition('x', model, {defaultPos: 'mid'}),
      ...encode.pointPosition('y', model, {defaultPos: 'mid'}),
      ...encode.nonPosition('size', model, {
        vgChannel: 'strokeWidth', // VL's line size is strokeWidth
      }),
      ...encode.defined(model),
    };
  },
};

export const trail: MarkCompiler = {
  vgMark: 'trail',
  encodeEntry: (model: UnitModel) => {
    return {
      ...encode.baseEncodeEntry(model, {
        align: 'ignore',
        baseline: 'ignore',
        color: 'include',
        size: 'include',
        orient: 'ignore',
        theta: 'ignore',
      }),
      ...encode.pointPosition('x', model, {defaultPos: 'mid'}),
      ...encode.pointPosition('y', model, {defaultPos: 'mid'}),
      ...encode.nonPosition('size', model),
      ...encode.defined(model),
    };
  },
};