Class Frustum

A volume bounded by six planes that face inward, most often the volume a camera sees

Each Camera3D has one as Camera3D#frustum. Test against it to skip work for things the camera can't see, or build your own from a matrix or from planes to cull against another volume.

Example

const onScreen = enemies.filter((enemy: Mesh3D) =>
  camera.frustum.intersectsSphere(enemy.boundingSphere),
);

Index

Constructors

constructor

new Frustum(
    p0?: Plane,
    p1?: Plane,
    p2?: Plane,
    p3?: Plane,
    p4?: Plane,
    p5?: Plane,
): Frustum
Creates a new Frustum

A plane left out defaults to new Plane(): normal (1, 0, 0), constant 0.
Parameters
- Optionalp0: Plane
  The first plane
- Optionalp1: Plane
  The second plane
- Optionalp2: Plane
  The third plane
- Optionalp3: Plane
  The fourth plane
- Optionalp4: Plane
  The fifth plane
- Optionalp5: Plane
  The sixth plane
Returns Frustum

Accessors

planesData

get planesData(): Float32Array
Advanced
The six planes as 24 floats, [nx, ny, nz, c] per plane in Frustum#getPlane order

This is the frustum's own storage, not a copy: writing to it changes the frustum. Pass it to your own shader to cull on the GPU.

Returns Float32Array
Example
```
device.queue.writeBuffer(frustumBuffer, 0, camera.frustum.planesData);
```

Methods

clone

clone(): Frustum
Creates a new Frustum with the same planes

Returns Frustum
The new frustum
Example
```
camera.cullFrustum = camera.frustum.clone();
```

containsPoint

containsPoint(point: PointData3D): boolean
Returns true when point lies inside this frustum (boundary is inclusive)
Parameters
- point: PointData3D
  The point to test
Returns boolean
Whether the point is inside this frustum
Example
```
marker.visible = !camera.frustum.containsPoint(objective.position);
```

copyFrom

copyFrom(frustum: Frustum): this
Copies frustum into this frustum
Parameters
- frustum: Frustum
  The frustum to copy from
Returns this
This frustum for chaining
Example
```
frozenFrustum.copyFrom(camera.frustum);
camera.cullFrustum = frozenFrustum;
```

copyTo

copyTo<T extends Frustum>(target: T): T
Copies this frustum into target and returns it
Type Parameters
- T extends Frustum
Parameters
- target: T
  The frustum to copy into
Returns T
The given target
Example
```
camera.frustum.copyTo(debugFrustum);
```

equals

equals(frustum: Frustum): boolean
Returns true when all six planes match frustum exactly, with no tolerance
Parameters
- frustum: Frustum
  The frustum to compare with
Returns boolean
Whether all six planes match
Example
```
if (!camera.frustum.equals(lastFrustum)) {
  lastFrustum.copyFrom(camera.frustum);
  refreshVisibleList();
}
```

getPlane

getPlane(index: number, out?: Plane): Plane
Writes plane index into out and returns it

After Frustum#setFromProjectionMatrix the planes are ordered right, left, bottom, top, far, near.
Parameters
- index: number
  The plane index, 0 to 5
- Optionalout: Plane
  Optional plane to write into; a new Plane when omitted
Returns Plane
The written plane
Example
```
const near = camera.frustum.getPlane(5, new Plane());
const distanceInFront = near.distanceToPoint(pickup.position);
```

intersectsBox

intersectsBox(box: Box): boolean
Returns true when box and this frustum overlap

Like most culling tests it errs towards true: a box just outside a corner of the frustum can pass, but a box that overlaps it never fails.
Parameters
- box: Box
  The box to test
Returns boolean
Whether the box and this frustum overlap
Example
```
building.getLocalBounds(bounds).applyMatrix4(building.worldTransform);
if (camera.frustum.intersectsBox(bounds)) updateWindowLights(building);
```

intersectsSphere

intersectsSphere(sphere: Sphere): boolean
Returns true when sphere and this frustum overlap

Like Frustum#intersectsBox it errs towards true near the frustum's corners. Empty spheres (radius < 0) never intersect.
Parameters
- sphere: Sphere
  The sphere to test
Returns boolean
Whether the sphere and this frustum overlap
Example
```
if (camera.frustum.intersectsSphere(enemy.boundingSphere)) enemy.updateAnimation(dt);
```

set

set(p0: Plane, p1: Plane, p2: Plane, p3: Plane, p4: Plane, p5: Plane): this
Sets the six planes of this frustum

Each plane's normal must be unit length and point into the volume.
Parameters
- p0: Plane
  The first plane
- p1: Plane
  The second plane
- p2: Plane
  The third plane
- p3: Plane
  The fourth plane
- p4: Plane
  The fifth plane
- p5: Plane
  The sixth plane
Returns this
This frustum for chaining
Example
```
camera.cullFrustum = new Frustum().set(
  new Plane(new Vector3(1, 0, 0), 20),
  new Plane(new Vector3(-1, 0, 0), 20),
  new Plane(new Vector3(0, 1, 0), 0),
  new Plane(new Vector3(0, -1, 0), 10),
  new Plane(new Vector3(0, 0, 1), 20),
  new Plane(new Vector3(0, 0, -1), 20),
);
```

setFromProjectionMatrix

setFromProjectionMatrix(matrix: Matrix4): this
Sets the six planes to the volume that matrix maps onto the screen

The planes come out in the space the matrix maps from: world space for a view-projection matrix, view space for a projection matrix alone. They are normalized, so distances to them are in that space's units. The matrix must map depth to [-1, 1], as Matrix4#makePerspective and Matrix4#makeOrthographic do.
Parameters
- matrix: Matrix4
  The matrix to extract clipping planes from
Returns this
This frustum for chaining
Example
```
const spotlightView = new Frustum().setFromProjectionMatrix(securityCamera.viewProjection);
const spotted = spotlightView.containsPoint(player.position);
```

toString

toString(): string
Returns a string representation of this frustum

Returns string
The string [@pixi/3d/math:Frustum]
Example
```
console.log(`${camera.frustum}`);
```

Class Frustum

Example

Index

Constructors

Accessors

Methods

Constructors

constructor

Parameters

Returns Frustum

Accessors

planesData

Returns Float32Array

Example

Methods

clone

Returns Frustum

Example

containsPoint

Parameters

Returns boolean

Example

copyFrom

Parameters

Returns this

Example

copyTo

Type Parameters

Parameters

Returns T

Example

equals

Parameters

Returns boolean

Example

getPlane

Parameters

Returns Plane

Example

intersectsBox

Parameters

Returns boolean

Example

intersectsSphere

Parameters

Returns boolean

Example

set

Parameters

Returns this

Example

setFromProjectionMatrix

Parameters

Returns this

Example

toString

Returns string

Example

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