animation-timeline-control

npm

Animation timeline is a TypeScript, no-dependency, canvas component designed to visualize and manipulate animation keyframes.

Features:

• Fast and customizable, rendered on a canvas.
• Snap, Zoom, Pan mode, multiple keyframes selection.
• Keyboard support.
• Drag multiple keyframes, drag keyframe ranges.
• Area virtualization - only visible canvas area is rendered.
• Native browser scrollbars are used.
• Horizontal scale with the automatically adjusted ticks.

Live Demo

• Live demo
• Run unittests

Usage

npm i animation-timeline-js

HTML/JavaScript

<div id="timeline"></div>
<script type="text/javascript">
   let rows = [
      {
        keyframes: [
          {
            val: 40,
          },
          {
            val: 3000
          }
        ]
      }];

    let timeline = new timelineModule.Timeline({id:'timeline'})

    timeline.setModel({ rows: rows });
</script>

Angular

import {
  Timeline,
  TimelineRow,
  TimelineModel,
  TimelineOptions,
} from "animation-timeline-js";

const model = { rows: [] as Array<TimelineRow> } as TimelineModel;
const options = {
  id: "timeline",
  rowsStyle: {
    height: 35,
  } as TimelineRowStyle,
} as TimelineOptions;

const timeline = new Timeline(options, model);

React

import React, { useEffect, useRef, useState } from "react";
import { Timeline, TimelineModel } from "animation-timeline-js";
type Props = {
  time?: number;
  model: TimelineModel;
};

function TimelineComponent(props: Props) {
  const { model, time } = props;
  const timelineElRef = useRef<HTMLDivElement>(null);
  const [timeline, setTimeline] = useState<Timeline>();

  useEffect(() => {
    let newTimeline: Timeline | null = null;
    // On component init
    if (timelineElRef.current) {
      newTimeline = new Timeline({ id: timelineElRef.current });
      // Here you can subscribe on timeline component events
      setTimeline(newTimeline);
    }

    // cleanup on component unmounted.
    return () => newTimeline?.dispose();
    // eslint-disable-next-line react-hooks/exhaustive-deps
  }, [timelineElRef.current]);

  // Example to subscribe and pass model or time update:
  useEffect(() => {
    timeline?.setModel(model);
  }, [model, timeline]);

  // Example to subscribe and pass model or time update:
  useEffect(() => {
    if (time || time === 0) {
      timeline?.setTime(time);
    }
  }, [time, timeline]);

  return <div style={{ width: "100%", minHeight: 300 }} ref={timelineElRef} />;
}
export default TimelineComponent;

// Usage: 
<TimelineComponent
  time={0}
  model={{
    rows: [
      {
        keyframes: [
          {
            val: 40,
          },
          {
            val: 3000,
          },
        ],
      },
    ],
  }}
></TimelineComponent>

Svelte

<script lang="ts">
  import { Timeline } from "animation-timeline-js";
  import type { TimelineModel } from "animation-timeline-js";
  import { onMount } from "svelte";

  export let time: number = 0;
  export let model: TimelineModel;

  let timelineEl!: HTMLDivElement;
  let timeline: Timeline | null = null;

  // Equivalent to componentDidMount and componentWillUnmount
  onMount(() => {
    let newTimeline: Timeline | null = null;
    if (timelineEl) {
      newTimeline = new Timeline({ id: timelineEl });
    }
    timeline = newTimeline;
    // Cleanup
    return () => {
      if (newTimeline) {
        newTimeline.dispose();
      }
    };
  });
  $: if (model) {
    // Reactive statements for model and time
    timeline?.setModel(model);
  }
  $: if (time || time === 0) {
    timeline?.setTime(time);
  }
</script>

<div bind:this={timelineEl} class="editor"></div>

<style>
  .editor {
    width: 100%;
    min-height: 300px;
  }
</style>

// Usage: 
<TimelineComponent
  time={0}
  model={{
    rows: [
      {
        keyframes: [
          {
            val: 40,
          },
          {
            val: 3000,
          },
        ],
      },
    ],
  }}
></TimelineComponent>

FAQ

• Can I have a tree view or list on the left/right? Answer: The outline/tree view has to be implemented separately. This gives additional control over the styling.
• Can I have separately connected groups of keyframes per row? Answer: Yes, multiple groups can be created per row. See <demo/demo.js> for details.
• Can I override the format of the gauge? Answer: Yes, the text can be changed. Just override the method _formatUnitsText.
• Can I have an individual style per row/keyframe/group? Answer: Yes, every instance can be styled separately if needed.
• Can I style individual keyframes? Answer: Yes, you have to override _renderKeyframe. See <demo/demo.js> for details.

Outline list

Outline list\tree can implemented as a separate HTML component and scrolling needs to be synchronized with the timeline. See the live demo

Tree View implementation

Next steps has to be followed to synchronize custom tree view html with the timeline component:

• Tree node that should have the same height as row model for the animation timeline.
• When some of the tree node entries are collapsed than corresponding animation timeline rows should become hidden.
• scrolling position has to be synchronized, this can be found here: live demo

Model

Keyframes model is used to pass keyframes and rows to be visualized. Component is using passed model for the visualization purpose and has no method to manage tracks or keyframes. It also means that any attached metadata can be passed and it will be preserved (Use case: you can attach additional data for each keyframe).

Read only and defined by the interfaces:

• TimelineModel
• TimelineRow
• TimelineKeyframe

Example on how to add a keyframe to existing model:

    const existingModel = timeline.getModel();
    existingModel.rows[0].keyframes.append({ val: 20 });
    timeline.setModel(existingModel);

Events/Methods and options

Events can be prevented by calling args.preventDefault()

Events subscription is performed in the JavaScript (not a DOM events):

this.timeline.onDragStarted((args: TimelineDragEvent) => {
    if (args) {
    }
});

Methods

Options

Options can be passed when timeline is created or by calling setOptions method. See all options in the TimelineOptions interface.

Keyboard shortcuts

Selection Mode

• Click - select single keyframe.
• Ctrl + Click - add new keyframe, toggle existing keyframe.

Keyframes can be marked as selectable = false to prevent interaction.

Zoom Mode

• Ctrl - reverse zoom in/zoom out.
• Ctrl + Mouse wheel - zoom to the current active cursor. (Same logic for the pan mode)

Interaction Modes

Selection - allow to select one or group of the keyframes.

• selection - Keyframe selection tool selecting single or group of keyframes.
• pan - Pan tool with the possibility to select keyframes.
• nonInteractivePan - Allow only pan without any keyframes interaction. Timeline still can be moved and controlled by option 'timelineDraggable'.
• zoom - zoom tool
• none - No iteraction, except moving a timeline. Timeline still can be moved and controlled by option 'timelineDraggable'.

Example:

  timeline.setInteractionMode('none');

For the TypeScript TimelineInteractionMode enum is used.

Timeline units and position

Expected that you have a component or engine that can execute playing a timeline. Ex: SVG has events to run the animations and report current time position. This component is meant only to visualize the position.

Time indicator position can be changed by a method call:

timeline.setTime(1000);

Current time can be fetched by a method call or by an event:

let value = timeline.getTime();

timeline.onTimeChanged((event: TimelineTimeChangedEvent) => {
  if(event.source !== TimelineEventSource.User) {
    value = event.val;
  }
});

Displayed units text can be changed by overriding a method:

timeline._formatUnitsText = (val)=> { return val + ' ms'; };

Styling

The timeline component is rendered as a canvas and has no HTML elements for CSS styling. Styles are applied as a part of the keyframes model and can be applied in a cascade order from bottom to the top:

• Global control setting (See TypeScript interface TimelineStyle)
• row styles (See TypeScript interface TimelineRowStyle)
• Keyframe group styles with the underlying keyframe styles. (TimelineGroupStyle)
• keyframe styles (See TypeScript interface TimelineKeyframeStyle)

Separate global styles for the timeline indicator are used:

• TimelineOptions - global component properties and styles.
  • TimelineStyle timeline indicator styles
  • TimelineCapStyle - cap of the timeline style.

Changes

See Changelog here

Development of the component

Build

run once to install development references:

  npm install

Run next command to pack JavaScript as a bundle:

  npm run build

Debug

VSCode is used as IDE and configuration is included to the project sources.

To debug project you should run command once files are changed:

npm run build

Then navigate to the VsCode debug window and click 'Launch Debug File'. Put breakpoint in any typescript file and trigger function from the browser.

Recommended extensions:

• markdownlint
• ESLint
• esbenp.prettier-vscode

Dev Dependencies

Component has no production dependencies when built. TypeScript Babel + Webpack is used to pack and transpile the library. Mocha and chai are used as test & assertion library.

Run Tests

npm run test

License

MIT