---
title: "Get Random Point on Ellipse"
description: "Demonstrates how to generate and update random coordinates within the area of a geometric ellipse."
phaser: "4.1.0"
size: "800x600"
files: 1
url: https://phaser.io/oss/examples/v4.1.0/geom/ellipse/view/get-random-point
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.

# Get Random Point on Ellipse

Demonstrates how to generate and update random coordinates within the area of a geometric ellipse.

A Phaser 4.1.0 example in [Geom / Ellipse](https://phaser.io/oss/examples/v4.1.0/geom/ellipse.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/geom/ellipse/view/get-random-point.

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

### get random point.js

```js
class Example extends Phaser.Scene
{
    index = 0;
    points;
    graphics;
    ellipse;

    create ()
    {
        this.ellipse = new Phaser.Geom.Ellipse(400, 300, 400, 250);

        this.graphics = this.add.graphics({ lineStyle: { width: 2, color: 0x00aaaa }, fillStyle: { color: 0xff0000 }});

        this.points = [];

        for (let i = 0; i < 25; i++)
        {
            // if we omit a parameter, new Point instance will be created and returned
            this.points.push(this.ellipse.getRandomPoint());
        }
    }

    update ()
    {
        this.index = ++this.index % 25;

        // we can also supply an instance of Point that will be modified
        this.ellipse.getRandomPoint(this.points[this.index]);

        this.graphics.clear();
        this.graphics.strokeEllipseShape(this.ellipse);

        for (let i = 0; i < 25; i++)
        {
            const p = this.points[i];
            this.graphics.fillRect(p.x - 4, p.y - 4, 8, 8);
        }
    }
}

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

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

## More in Ellipse

- [Adjust Ellipse Size](https://phaser.io/oss/examples/v4.1.0/geom/ellipse/view/adjust-size.md): Demonstrates how to dynamically update the width and height of a geometric ellipse based on pointer movement and redraw it using a Graphics object.
- [Create Ellipse](https://phaser.io/oss/examples/v4.1.0/geom/ellipse/view/create-ellipse.md): Create a geometric ellipse object and draw its outline to the screen using a Graphics object.
- [Ellipse Area](https://phaser.io/oss/examples/v4.1.0/geom/ellipse/view/area.md): Calculate the area of an ellipse and visualize it using a square of equivalent size as the ellipse dimensions change.
- [Ellipse Circumference](https://phaser.io/oss/examples/v4.1.0/geom/ellipse/view/circumference.md): Calculate the circumference of an ellipse and compare it to a square and a circle with the same perimeter length.
- [Ellipse Circumference Point](https://phaser.io/oss/examples/v4.1.0/geom/ellipse/view/circumference-point.md): Demonstrates how to calculate a specific coordinate on the perimeter of an ellipse based on a given angle using the CircumferencePoint method.
- [Ellipse Clone](https://phaser.io/oss/examples/v4.1.0/geom/ellipse/view/clone.md): Create copies of a geometric ellipse using the Clone method to generate a sequence of expanding shapes.
- [Ellipse Contains Point](https://phaser.io/oss/examples/v4.1.0/geom/ellipse/view/contains.md): Demonstrates how to check if a specific coordinate, such as the mouse pointer, is located inside the area of an ellipse.
- [Ellipse Contains Point](https://phaser.io/oss/examples/v4.1.0/geom/ellipse/view/contains-point.md): Demonstrates using the Ellipse.ContainsPoint function to detect if a moving coordinate is located within the bounds of an ellipse shape.
- [Ellipse Contains Rectangle](https://phaser.io/oss/examples/v4.1.0/geom/ellipse/view/contains-rect.md): Demonstrates how to check if a Rectangle shape is entirely contained within the bounds of an Ellipse.
- [Ellipse Copy From](https://phaser.io/oss/examples/v4.1.0/geom/ellipse/view/copy-from.md): Demonstrates using Phaser.Geom.Ellipse.CopyFrom to duplicate the properties of one ellipse geometry object into another.
- [Ellipse Equals](https://phaser.io/oss/examples/v4.1.0/geom/ellipse/view/equals.md): Demonstrates how to use the Ellipse Equals method to determine if two ellipse geometry objects share the exact same position and dimensions.
- [Ellipse Get Bounds](https://phaser.io/oss/examples/v4.1.0/geom/ellipse/view/get-bounds.md): Demonstrates how to calculate and update the axis-aligned bounding rectangle of a geometric ellipse as it moves and changes size.
- [All 26 examples in Ellipse](https://phaser.io/oss/examples/v4.1.0/geom/ellipse.md)

---

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