> ## Documentation Index
> Fetch the complete documentation index at: https://rive.app/docs/llms.txt
> Use this file to discover all available pages before exploring further.

# Path Effect Scripts

> Create custom path effects using Rive scripting

export const Demos = ({examples, runtime, columns = 2, children, childrenIndex = 0, learnByExample = false}) => {
  const examplesData = {
    ikConstraint: {
      title: 'IK Constraints',
      description: 'Check out this example to see IK constraints in action.',
      image: "https://static.rive.app/docs/ik-constraint.gif",
      stateMachines: "State Machine 1",
      links: {
        editor: "https://rive.app/community/files/28080-53039-ik-constraint/"
      }
    },
    cachingARiveFile: {
      title: 'Caching a Rive File',
      description: 'Load the .riv into memory once, use it multiple times.',
      riv: 'https://static.rive.app/rivs/rives_animated_emojis.riv',
      stateMachines: "State Machine 1",
      artboard: "Emoji_package",
      links: {
        web: "https://codesandbox.io/p/sandbox/rive-js-caching-a-rive-file-g675my?file=%2Fsrc%2Findex.ts%3A9%2C1",
        react: "https://codesandbox.io/p/sandbox/rive-react-caching-a-rive-file-53gmdf?file=%2Fsrc%2FApp.tsx"
      },
      source: ["https://rive.app/marketplace/24644-46045-caching-a-rive-file-at-runtime/"]
    },
    dataBindingArtboards: {
      title: 'Data Binding Artboards',
      description: 'Swap an artboard with another artboard from the same .riv or one loaded at runtime.',
      image: '/images/runtimes/rive-data-bind-components.webp',
      links: {
        web: 'https://codesandbox.io/p/sandbox/rive-js-data-binding-artboards-jx3pf9?file=%2Fsrc%2Findex.mjs%3A5%2C19',
        react: 'https://codesandbox.io/p/sandbox/rive-react-data-binding-artboards-kmvzh8?file=%2Fsrc%2FApp.tsx',
        flutter: 'https://github.com/rive-app/rive-flutter/blob/master/example/lib/examples/databinding_artboards.dart',
        reactNative: 'https://github.com/rive-app/rive-nitro-react-native/blob/main/example/src/demos/DataBindingArtboardsExample.tsx',
        android: "https://github.com/rive-app/rive-android/blob/master/app/src/main/java/app/rive/runtime/example/ComposeArtboardBindingActivity.kt"
      },
      source: ["https://rive.app/marketplace/24641-46042-data-binding-artboards/", "https://rive.app/marketplace/24642-47536-data-binding-artboards/"]
    },
    dataBindingImages: {
      title: 'Data Binding Images',
      description: 'Replace images at runtime using data binding images with javascript.',
      image: '/images/runtimes/rive-db-images.webp',
      links: {
        web: 'https://codesandbox.io/p/sandbox/objective-cohen-sqwh9q?file=%2Fsrc%2Findex.ts',
        flutter: 'https://github.com/rive-app/rive-flutter/blob/master/example/lib/examples/databinding_images.dart',
        android: "https://github.com/rive-app/rive-android/blob/master/app/src/main/java/app/rive/runtime/example/ComposeImageBindingActivity.kt"
      },
      source: ["https://rive.app/marketplace/25472-47537-data-binding-images/"]
    },
    dataBindingLists: {
      title: 'Data Binding Lists',
      description: 'Add, remove, edit, and swap items in your data binding list.',
      image: '/images/runtimes/rive-db-lists.webp',
      links: {
        web: 'https://codesandbox.io/p/sandbox/suspicious-hertz-2lg4m8?file=%2Fsrc%2Findex.ts',
        react: 'https://codesandbox.io/p/sandbox/rive-react-data-binding-lists-4msh9z?file=%2Fsrc%2FApp.tsx',
        flutter: 'https://github.com/rive-app/rive-flutter/blob/master/example/lib/examples/databinding_lists.dart',
        android: "https://github.com/rive-app/rive-android/blob/master/app/src/main/java/app/rive/runtime/example/ComposeListActivity.kt"
      },
      source: ["https://rive.app/marketplace/25474-47539-data-binding-lists/"]
    },
    dataBindingQuickStart: {
      title: "Data Binding",
      description: "Get started with Data Binding at runtime.",
      image: "/images/runtimes/rewards.gif",
      links: {
        flutter: "https://github.com/rive-app/rive-flutter/blob/master/example/lib/examples/databinding.dart",
        reactNative: "https://github.com/rive-app/rive-react-native/blob/main/example/app/(examples)/DataBinding.tsx",
        unity: "https://github.com/rive-app/rive-unity-examples/blob/main/getting-started/Assets/RewardsController.cs",
        apple: "https://github.com/rive-app/rive-ios/blob/main/Example-iOS/Source/Examples/SwiftUI/RewardsView.swift",
        android: "https://github.com/rive-app/rive-android/blob/master/app/src/main/java/app/rive/runtime/example/ComposeDataBindingActivity.kt"
      },
      source: ["https://rive.app/marketplace/25475-47540-data-binding-demo/"]
    },
    dataBindingSolos: {
      title: "Data Binding Solos",
      description: "Control solos at runtime using strings, numbers, or enums.",
      image: '/images/runtimes/data-binding-solos.gif',
      links: {
        react: "https://codesandbox.io/p/sandbox/rive-react-controlling-solos-at-runtime-ctcnlx?file=%2Fsrc%2FApp.tsx"
      },
      source: ["https://rive.app/marketplace/24643-46044-data-binding-solos/"]
    },
    googleAppAds: {
      title: "Google App Ads",
      description: "How to make an interactive Google App with Rive.",
      image: "/images/runtimes/google-app-ads.png",
      links: {
        mobile: "https://github.com/rive-app/rive-use-cases/tree/main/rive-google-ads"
      }
    },
    layouts: {
      title: "Responsive Layouts",
      description: "Create responsive layouts that adapt to different screen sizes.",
      riv: "https://static.rive.app/rivs/layouts_demo.riv",
      stateMachines: "State Machine 1",
      artboard: "Demo",
      links: {
        web: "https://codesandbox.io/p/devbox/rive-responsive-layout-js-forked-m77nlw",
        react: "https://codesandbox.io/p/devbox/rive-responsive-layouts-react-forked-nmpv39?file=%2Fsrc%2FApp.tsx",
        flutter: "https://github.com/rive-app/rive-flutter/blob/master/example/lib/examples/responsive_layouts.dart",
        reactNative: "https://github.com/rive-app/rive-react-native/blob/main/example/app/(examples)/ResponsiveLayout.tsx",
        android: "https://github.com/rive-app/rive-android/blob/master/app/src/main/java/app/rive/runtime/example/ComposeLayoutActivity.kt"
      },
      source: ["https://rive.app/marketplace/24638-46038-layouts-demo/"]
    },
    fontsHostedCompressed: {
      title: 'Load a Compressed Font for Web',
      description: 'Dynamically load a font asset from a hosted location with compression.',
      image: '/images/runtimes/brotli-compressed-fonts.webp',
      links: {
        react: 'https://codesandbox.io/p/sandbox/prod-sound-6yc5xl?file=%2Fsrc%2FApp.tsx%3A19%2C1'
      },
      source: ["https://rive.app/marketplace/25473-47538-loading-compressed-fonts-web/"]
    },
    quickStart: {
      title: "Data Binding Quick Start",
      image: '/images/runtimes/quick-start.gif',
      description: 'Load and control your Rive (.riv) file.',
      links: {
        web: 'https://codesandbox.io/p/sandbox/rive-quick-start-js-xmwcm6?file=%2Fsrc%2Findex.ts',
        react: 'https://codesandbox.io/p/sandbox/rive-react-quick-start-4xy76h?file=%2Fsrc%2FApp.tsx%3A77%2C14',
        reactJs: 'https://codesandbox.io/p/devbox/rive-react-vanilla-js-quick-start-kz66t4?file=%2Fsrc%2FApp.tsx%3A53%2C7',
        reactNative: 'https://github.com/rive-app/rive-nitro-react-native/blob/main/example/src/demos/QuickStart.tsx',
        unity: '/game-runtimes/unity/tutorials/health-bar'
      },
      source: ["https://rive.app/marketplace/24637-46037-health-bar-data-binding-quick-start/"]
    },
    quickStartReact: {
      title: "Data Binding Quick Start",
      image: '/images/runtimes/quick-start.gif',
      description: 'Load and control your Rive (.riv) file.',
      links: {
        react: 'https://codesandbox.io/p/sandbox/rive-react-quick-start-4xy76h?file=%2Fsrc%2FApp.tsx%3A77%2C14',
        reactJs: 'https://codesandbox.io/p/devbox/rive-react-vanilla-js-quick-start-kz66t4?file=%2Fsrc%2FApp.tsx%3A53%2C7'
      },
      source: ["https://rive.app/marketplace/24637-46037-health-bar-data-binding-quick-start/"]
    },
    scriptingDrawingShapes: {
      title: "Drawing with Scripting",
      image: "https://static.rive.app/docs/drawing-demo.png",
      description: "Draw a squirkle, a star, and an animated wave with scripting.",
      links: {
        editor: "https://rive.app/community/files/25751-48087-drawing-shapes-with-scripting"
      }
    },
    scriptingMasonry: {
      title: "Masonry Layout",
      image: "https://static.rive.app/docs/masonry.png",
      description: "Create a masonry layout using a Layout script.",
      links: {
        editor: "https://rive.app/community/files/25826-masonry-layout/"
      }
    },
    scriptingParticleEmitter: {
      title: "Particle Emitter",
      riv: "https://static.rive.app/rivs/particle-demo.riv",
      artboard: "Demo",
      description: "A small, self contained particle system for Rive node and layout scripts.",
      links: {
        editor: "https://rive.app/community/files/28062-53012-particle-librar/"
      }
    },
    scriptingTippingConverter: {
      title: "Custom Converter",
      image: "https://static.rive.app/docs/tipping-scripting-converter.gif",
      description: "Calculate the bill total using the converter's input value added to data binding values.",
      links: {
        editor: "https://uat.rive.app/community/files/610-1126-custom-converter-with-scripting"
      }
    },
    scriptingUnitTesting: {
      title: "Unit Testing",
      image: "https://static.rive.app/docs/scripting-default-thumb.png",
      description: "This hands-on example demonstrates unit testing rgbToHex and hexToRgb color utilities.",
      links: {
        editor: "https://rive.app/community/files/25752-48088-test-script"
      }
    },
    scriptingSnakeGame: {
      title: "Snake - Complete Game",
      image: "https://static.rive.app/docs/snake-game.png",
      description: "Check out this complete game built entirely with Rive using scripting.",
      links: {
        editor: "https://rive.app/community/files/25748-48110-snake-game/"
      }
    },
    scriptingMultiTouch: {
      title: "Tracking Multi-touch",
      image: "https://static.rive.app/docs/scripting-default-thumb.png",
      description: "Keep track of every finger.",
      links: {
        editor: "https://rive.app/community/files/25754-48090-multi-touch-with-scripting"
      }
    },
    scriptingNestedPointers: {
      title: "Nested Pointer Events",
      image: "https://static.rive.app/docs/scripting-default-thumb.png",
      description: "Pass pointer events from the parent component to the instantiated children.",
      links: {
        editor: "https://rive.app/community/files/25750-48086-scripting-nested-pointer-events/"
      }
    },
    scriptingBoilPathEffect: {
      title: "Boiling Path Effect",
      image: "https://static.rive.app/docs/boiling-effect.gif",
      description: "Apply a boiling effect to any path using scripting.",
      links: {
        editor: "https://rive.app/community/files/25767-48113-scripting-path-effect-boil"
      }
    },
    scriptingTextPathEffect: {
      title: "Text Path Effect",
      image: "https://static.rive.app/docs/text-path-effect.gif",
      description: "Control a text path using scripting.",
      links: {
        editor: "https://rive.app/community/files/25823-text-path-effects/"
      }
    },
    scriptingDrawImages: {
      title: "Render an Image with Scripting",
      image: "https://static.rive.app/docs/render-image-with-scripting.jpg",
      description: "Draw an image, give it transforms, control its mesh, and add clipping all through scripting.",
      links: {
        editor: "https://rive.app/community/files/26406-draw-an-image-with-scripting"
      }
    },
    scriptingSlotMachine: {
      title: "Slot Machine - Complete Game",
      image: "https://static.rive.app/docs/slot-machine.png",
      description: "Build a complete casino game using scripting.",
      links: {
        editor: "https://rive.app/community/files/25759-slot-machine-game-with-scripting/"
      }
    },
    scriptingLists: {
      title: "Scripting Lists",
      image: "/images/runtimes/rive-db-lists.webp",
      description: "Add, remove, edit, and swap items in your data binding list using Rive scripting.",
      links: {
        editor: "https://rive.app/community/files/27098-51051-scripting-lists"
      }
    },
    scriptingPlinko: {
      title: "Plinko - Complete Game",
      image: "https://static.rive.app/docs/scripting-plinko-game.png",
      description: "Build a complete Plinko game using Layout, Node, and Path Effect scripts.",
      links: {
        editor: "https://rive.app/marketplace/25772-blinko-scripted-game/"
      }
    },
    constraints: {
      title: "Constraints",
      image: "https://static.rive.app/docs/constraints.gif",
      description: "Transform, Translate, Scale, and Rotation Constraints.",
      links: {
        editor: "https://rive.app/community/files/28081-53040-constraints/"
      }
    }
  };
  const runtimesInOrder = ['web', 'react', 'reactJs', 'reactNative', 'flutter', 'apple', 'android', 'unity', 'unreal', 'mobile', 'editor'];
  const runtimeTitles = {
    web: 'Web',
    reactJs: 'React (Imperative)',
    react: 'React',
    reactNative: "React Native",
    flutter: 'Flutter',
    apple: 'Apple',
    android: 'Android',
    unity: 'Unity',
    unreal: 'Unreal',
    mobile: 'Mobile',
    editor: 'Try in Rive'
  };
  const riveInstances = useRef([]);
  const initRives = () => {
    const rive = window.rive;
    examples.forEach(example => {
      const {riv, stateMachines = "State Machine 1", artboard} = examplesData[example];
      if (riv) {
        const canvasId = `rive-canvas-${example}`;
        const canvas = document.getElementById(canvasId);
        if (canvas) {
          const r = new rive.Rive({
            src: riv,
            stateMachines,
            canvas,
            artboard,
            autoBind: true,
            autoplay: true,
            Layout: new rive.Layout({
              fit: rive.Fit.Layout
            }),
            onLoad: () => {
              r.resizeDrawingSurfaceToCanvas();
              riveInstances.current.push(r);
            }
          });
        }
      }
    });
  };
  useEffect(() => {
    if (window.rive) {
      initRives();
      return;
    }
    const checkRive = () => {
      if (window.rive) {
        initRives();
        window.removeEventListener("rive-loaded", checkRive);
      }
    };
    const handleResize = () => {
      riveInstances.current.forEach(instance => {
        instance.resizeDrawingSurfaceToCanvas();
      });
    };
    window.addEventListener("rive-loaded", checkRive);
    window.addEventListener("resize", handleResize);
    return () => {
      window.removeEventListener("rive-loaded", checkRive);
      window.removeEventListener("resize", handleResize);
      riveInstances.current.forEach(instance => {
        instance.cleanup();
      });
    };
  }, []);
  const RuntimeLink = ({link, runtime}) => {
    if (!link) return null;
    if (runtime === 'editor') {
      link = `${link}?utm_source=docs&utm_medium=docs_demo_card`;
    }
    return <a href={link} target="_blank" className="cursor-pointer border border-neutral-600 hover:border-white rounded-[4px] text-14 py-1 px-5 mr-[10px] mb-[10px]">
        {runtimeTitles[runtime]}
      </a>;
  };
  const CardContainer = ({children: content}) => {
    return <div className="flex flex-col card block font-normal group relative my-2 ring-2 ring-transparent rounded-2xl bg-white dark:bg-background-dark border border-gray-950/10 dark:border-white/10 overflow-hidden w-full">
        {content}
      </div>;
  };
  const getSrc = imageSrc => {
    if (location.hostname === "localhost" && imageSrc.startsWith("/images/")) {
      return imageSrc;
    } else if (imageSrc.startsWith('https:')) {
      return imageSrc;
    }
    return `https://rive.app/docs${imageSrc}`;
  };
  return <div className={`
        card-group not-prose grid gap-x-4
        grid-cols-1
        ${columns >= 2 && "md:grid-cols-2"}
        ${columns >= 3 && "xl:grid-cols-3 xl:w-[67rem] xl:max-w-[calc(100vw-25rem)]"}
      `}>
      {examples.map((example, index) => {
    const {title, image, links, description, source, riv} = examplesData[example];
    const canvasId = `rive-canvas-${example}`;
    return <>
            {index === childrenIndex && children}
            <CardContainer key={canvasId}>
              <div className="w-full h-0 relative pb-[75%]">
                <div className="absolute inset-0">
                  {image && <img alt={title} className="w-full object-cover object-center" src={getSrc(image)} />}

                  {riv && !image && <canvas id={canvasId} style={{
      width: "100%",
      height: "100%"
    }} />}
                </div>
              </div>
              <div className="flex flex-grow flex-col px-6 py-5 relative" data-component-part="card-content-container">
                <div className="flex flex-col grow">
                  <h2 className="not-prose font-semibold text-base text-gray-800 dark:text-white" data-component-part="card-title">{learnByExample ? "Learn by Example" : title}</h2>

                  <div className="flex flex-col grow prose mt-1 font-normal text-sm leading-6 text-gray-600 dark:text-gray-400" data-component-part="card-content">
                    <div className="grow flex flex-col">
                      {description && !learnByExample && <p>{description}</p>}
                      {source && source.length > 0 && <p className="mt-3">
                            {source.map((item, index) => {
      if (source.length == 1) {
        return <>Open the <a href={item}>Rive file</a>.</>;
      }
      if (index == 0) {
        return <>Open <a href={item}>Rive file 1</a></>;
      }
      return <>, <a href={item}>file {index + 1}</a></>;
    })}
                          </p>}
                    </div>
                    {<div className="mt-6 flex flex-wrap">
                        {runtimesInOrder.map(currentRuntime => {
      if (runtime && currentRuntime !== runtime) return;
      return <RuntimeLink key={currentRuntime} runtime={currentRuntime} link={links[currentRuntime]} />;
    })}
                      </div>}
                  </div>
                </div>
              </div>
            </CardContainer>
          </>;
  })}
    </div>;
};

Path Effects are Rive scripts that modify and transform path geometry in real-time. They give you programmatic control over the shape and structure of paths in your animations, enabling effects like warping, distortion, animation, and procedural modifications.

## Creating a Path Effect

[Create a new script](/scripting/creating-scripts) and select **Path Effect** as the type.

## Examples

<Demos
  examples={[
"scriptingBoilPathEffect",
"scriptingTextPathEffect",
]}
/>

## Anatomy of a Path Effect Script

### Methods

* *init (optional)*
  Called once when the path effect is created. Use this to set up initial state. Returns true if initialization succeeds.
* *update (required)*
  The core method where path transformation happens. Receives the original `PathData` and returns a modified version. This is where you manipulate the path's geometry.
* *advance (optional)*
  Called every frame with elapsed time in seconds. Returns true to continue receiving advance calls. Useful for animated effects that change over time.

## Working with `PathData`

`PathData` provides access to a path's drawing commands (`moveTo`, `lineTo`, `cubicTo`, `quadTo`, `close`). You can:

* Read existing commands using indexing
* Get the command count with `#pathData`
* Create new paths and add commands
* Use measurement tools like `contours()` and `measure()` for advanced operations

```lua theme={null}
type MyPathEffect = {
  context: Context,
}

function init(self: MyPathEffect, context: Context): boolean
  self.context = context
  return true
end

function update(self: MyPathEffect, inPath: PathData): PathData
  local path = Path.new()
  return path
end

function advance(self: MyPathEffect, seconds: number): boolean
  return true
end

-- Return a factory function that Rive uses to build the Path Effect instance.
return function(): PathEffect<MyPathEffect>
  return {
    init = init,
    update = update,
    advance = advance,
    context = late(),
  }
end
```

<Note>
  If a Path Effect script changes over time, call `markNeedsUpdate()` on the effect context from `advance()`. This tells Rive to recalculate the effect on the next frame, even when the source path itself has not changed.

  Without this, the effect may appear to freeze because Rive has no signal that the path output is changing. This is especially important for animated path effects inside nested components, where the source path may remain static while the script continues updating its own internal values.

  ```lua highlight={11} theme={null}
  local function init(self: WaveyEffect, context: Context): boolean
    self.context = context
    self.time = 0.0
    return true
  end

  local function advance(self: WaveyEffect, seconds: number): boolean
    self.time += seconds * math. clamp(self. speed, 0.0, 20.0)

    if self. context then
      self.context: markNeedsUpdate()
    end

    return true
  end
  ```
</Note>

## Add the Scripted Path Effect to a Stroke

Select or add a stroke to a shape:

1. Open the Options menu.
2. Select the Effects Tab and click the '+' to add an effect.
3. Find your effects under the Script Effects menu option.
4. Any inputs you have defined will apepar and can be edited here.

<img src="https://mintcdn.com/rive/7dSyPIbQmOsAVUjI/images/scripting/add-path-effect-to-stroke.png?fit=max&auto=format&n=7dSyPIbQmOsAVUjI&q=85&s=896b962c6f4db04c2d96373376a762cc" alt="Add Path Effect to a Stroke" width="1268" height="914" data-path="images/scripting/add-path-effect-to-stroke.png" />

## Adding Inputs

See [Script Inputs](/scripting/script-inputs).