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OrthographicFrustum

new Cesium.OrthographicFrustum(options)
engine/Source/Core/OrthographicFrustum.js 30

The viewing frustum is defined by 6 planes. Each plane is represented by a Cartesian4 object, where the x, y, and z components define the unit vector normal to the plane, and the w component is the distance of the plane from the origin/camera position.
Name Type Description
options object optional An object with the following properties:
Name Type Default Description
width number optional The width of the frustum in meters.
aspectRatio number optional The aspect ratio of the frustum's width to it's height.
near number 1.0 optional The distance of the near plane.
far number 500000000.0 optional The distance of the far plane.
Example:
const maxRadii = ellipsoid.maximumRadius;

const frustum = new Cesium.OrthographicFrustum();
frustum.near = 0.01 * maxRadii;
frustum.far = 50.0 * maxRadii;

Members

static Cesium.OrthographicFrustum.packedLength : number
engine/Source/Core/OrthographicFrustum.js 72

The number of elements used to pack the object into an array.

aspectRatio : number
engine/Source/Core/OrthographicFrustum.js 48

The aspect ratio of the frustum's width to it's height.
Default Value: undefined

far : number
engine/Source/Core/OrthographicFrustum.js 64

The distance of the far plane.
Default Value: 500000000.0;

near : number
engine/Source/Core/OrthographicFrustum.js 56

The distance of the near plane.
Default Value: 1.0

readonly projectionMatrix : Matrix4
engine/Source/Core/OrthographicFrustum.js 181

Gets the orthographic projection matrix computed from the view frustum.

width : number
engine/Source/Core/OrthographicFrustum.js 40

The horizontal width of the frustum in meters.
Default Value: undefined

Methods

static Cesium.OrthographicFrustum.pack(value, array, startingIndex) → Array.<number>
engine/Source/Core/OrthographicFrustum.js 83

Stores the provided instance into the provided array.
Name Type Default Description
value OrthographicFrustum The value to pack.
array Array.<number> The array to pack into.
startingIndex number 0 optional The index into the array at which to start packing the elements.
Returns:
The array that was packed into

static Cesium.OrthographicFrustum.unpack(array, startingIndex, result) → OrthographicFrustum
engine/Source/Core/OrthographicFrustum.js 107

Retrieves an instance from a packed array.
Name Type Default Description
array Array.<number> The packed array.
startingIndex number 0 optional The starting index of the element to be unpacked.
result OrthographicFrustum optional The object into which to store the result.
Returns:
The modified result parameter or a new OrthographicFrustum instance if one was not provided.

clone(result) → OrthographicFrustum
engine/Source/Core/OrthographicFrustum.js 266

Returns a duplicate of a OrthographicFrustum instance.
Name Type Description
result OrthographicFrustum optional The object onto which to store the result.
Returns:
The modified result parameter or a new OrthographicFrustum instance if one was not provided.

computeCullingVolume(position, direction, up) → CullingVolume
engine/Source/Core/OrthographicFrustum.js 215

Creates a culling volume for this frustum.
Name Type Description
position Cartesian3 The eye position.
direction Cartesian3 The view direction.
up Cartesian3 The up direction.
Returns:
A culling volume at the given position and orientation.
Example:
// Check if a bounding volume intersects the frustum.
const cullingVolume = frustum.computeCullingVolume(cameraPosition, cameraDirection, cameraUp);
const intersect = cullingVolume.computeVisibility(boundingVolume);

equals(other) → boolean
engine/Source/Core/OrthographicFrustum.js 294

Compares the provided OrthographicFrustum componentwise and returns true if they are equal, false otherwise.
Name Type Description
other OrthographicFrustum optional The right hand side OrthographicFrustum.
Returns:
true if they are equal, false otherwise.

equalsEpsilon(other, relativeEpsilon, absoluteEpsilon) → boolean
engine/Source/Core/OrthographicFrustum.js 319

Compares the provided OrthographicFrustum componentwise and returns true if they pass an absolute or relative tolerance test, false otherwise.
Name Type Default Description
other OrthographicFrustum The right hand side OrthographicFrustum.
relativeEpsilon number The relative epsilon tolerance to use for equality testing.
absoluteEpsilon number relativeEpsilon optional The absolute epsilon tolerance to use for equality testing.
Returns:
true if this and other are within the provided epsilon, false otherwise.

getPixelDimensions(drawingBufferWidth, drawingBufferHeight, distance, pixelRatio, result) → Cartesian2
engine/Source/Core/OrthographicFrustum.js 243

Returns the pixel's width and height in meters.
Name Type Description
drawingBufferWidth number The width of the drawing buffer.
drawingBufferHeight number The height of the drawing buffer.
distance number The distance to the near plane in meters.
pixelRatio number The scaling factor from pixel space to coordinate space.
result Cartesian2 The object onto which to store the result.
Returns:
The modified result parameter or a new instance of Cartesian2 with the pixel's width and height in the x and y properties, respectively.
Throws:
Example:
// Example 1
// Get the width and height of a pixel.
const pixelSize = camera.frustum.getPixelDimensions(scene.drawingBufferWidth, scene.drawingBufferHeight, 0.0, scene.pixelRatio, new Cesium.Cartesian2());
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