---
title: "Quadratic Bezier Curve"
description: "Create a quadratic Bezier curve and animate a point along its path using a tween to interpolate the position."
phaser: "4.1.0"
size: "800x600"
files: 1
url: https://phaser.io/oss/examples/v4.1.0/paths/curves/view/quadratic-bezier-curve
site: Phaser - https://phaser.io
---

> This page is about the open-source Phaser framework, for writing a game's code by hand. To make a game with AI, use Phaser AE (https://phaser.io/): the desk's tools work with Web MCP, and the CLI works with your own coding agent. See "For AI agents: Phaser AE" at the end of this page.

# Quadratic Bezier Curve

Create a quadratic Bezier curve and animate a point along its path using a tween to interpolate the position.

A Phaser 4.1.0 example in [Paths / Curves](https://phaser.io/oss/examples/v4.1.0/paths/curves.md). It runs at 800 × 600, and loads its assets from https://cdn.phaserfiles.com/v410. See it running, with its code, at https://phaser.io/oss/examples/v4.1.0/paths/curves/view/quadratic-bezier-curve.

To run it, load Phaser 4.1.0 (`https://cdn.jsdelivr.net/npm/phaser@4.1.0/dist/phaser.min.js`), then the file, on a page with a `<div id="game-container">`.

## Code

### quadratic bezier curve.js

```js
class Example extends Phaser.Scene
{
    graphics;
    curve;
    path;

    create ()
    {
        this.graphics = this.add.graphics();

        this.path = { t: 0, vec: new Phaser.Math.Vector2() };

        const startPoint = new Phaser.Math.Vector2(100, 500);
        const controlPoint1 = new Phaser.Math.Vector2(50, 100);
        const endPoint = new Phaser.Math.Vector2(700, 500);

        this.curve = new Phaser.Curves.QuadraticBezier(startPoint, controlPoint1, endPoint);

        this.tweens.add({
            targets: this.path,
            t: 1,
            ease: 'Sine.easeInOut',
            duration: 2000,
            yoyo: true,
            repeat: -1
        });
    }

    update ()
    {
        this.graphics.clear();

        this.graphics.lineStyle(1, 0x00ff00, 1);

        this.curve.draw(this.graphics);

        this.curve.getPoint(this.path.t, this.path.vec);

        this.graphics.fillStyle(0xff0000, 1);
        this.graphics.fillCircle(this.path.vec.x, this.path.vec.y, 16);
    }
}

const config = {
    scale: { mode: Phaser.Scale.FIT },
    type: Phaser.AUTO,
    width: 800,
    height: 600,
    backgroundColor: '#2d2d2d',
    parent: 'game-container',
    scene: Example
};

const game = new Phaser.Game(config);
```

## More in Curves

- [Cubic Bezier Bounds](https://phaser.io/oss/examples/v4.1.0/paths/curves/view/cubic-bezier-bounds.md): Learn how to calculate and display the bounding box of a Cubic Bezier curve. This example features interactive control points that update the curve shape and its bounds in real-time.
- [Cubic Bezier Curve](https://phaser.io/oss/examples/v4.1.0/paths/curves/view/cubic-bezier-curve.md): Create a cubic Bezier curve using start, end, and two control points, and animate an object moving along the path using a tween.
- [Cubic Bezier Curve Debug](https://phaser.io/oss/examples/v4.1.0/paths/curves/view/cubic-bezier-curve-debug.md): Visualizes the mathematical construction of a Cubic Bezier curve using linear interpolation across control points and intermediate lines.
- [Cubic Bezier Path Points](https://phaser.io/oss/examples/v4.1.0/paths/curves/view/point-types.md): Demonstrates how to extract evenly spaced points or specific coordinates along a Cubic Bezier curve using getPoints and getPoint.
- [Drag Cubic Bezier Curve](https://phaser.io/oss/examples/v4.1.0/paths/curves/view/drag-cubic-bezier-curve.md): Create and manipulate a Cubic Bezier curve by dragging its start, end, and control points, while an object follows the path via a tween.
- [Drag Quadratic Bezier Curve](https://phaser.io/oss/examples/v4.1.0/paths/curves/view/drag-quadratic-bezier-curve.md): Manipulate a Quadratic Bezier curve in real-time by dragging its start, end, and control points while an object animates along the path.
- [Drag Spline Curve](https://phaser.io/oss/examples/v4.1.0/paths/curves/view/drag-spline-curve.md): Demonstrates an interactive spline curve where control points can be dragged to reshape the path in real-time while an object follows the curve.
- [Draggable Line Curve](https://phaser.io/oss/examples/v4.1.0/paths/curves/view/drag-line-curve.md): Demonstrates how to create a Line curve and interactively update its start and end points using draggable handle objects.
- [Ellipse Curve Animation](https://phaser.io/oss/examples/v4.1.0/paths/curves/view/ellipse-curve.md): Demonstrates how to create an elliptical path and animate its x and y radius over time while moving an object along the curve.
- [Ellipse Curve Bounds](https://phaser.io/oss/examples/v4.1.0/paths/curves/view/ellipse-curve-bounds.md): Demonstrates how to calculate and visualize the bounding box of an interactive Ellipse curve. Includes real-time controls for radius, rotation, and start/end angles.
- [Get Point at Distance on Line Curve](https://phaser.io/oss/examples/v4.1.0/paths/curves/view/get-distance-on-line-curve.md): Demonstrates how to find the specific coordinates of a point located at a certain pixel distance along a line curve using getTFromDistance.
- [Get Point from Spline Curve](https://phaser.io/oss/examples/v4.1.0/paths/curves/view/get-point-from-spline-curve.md): Demonstrates how to use getPointAt to find specific coordinates along a Spline curve based on a normalized value between 0 and 1.
- [All 29 examples in Curves](https://phaser.io/oss/examples/v4.1.0/paths/curves.md)

---

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