Billboard

new Billboard

A viewport-aligned image positioned in the 3D scene, that is created and rendered using a BillboardCollection. A billboard is created and its initial properties are set by calling BillboardCollection#add. Any of the billboard's properties can be changed at any time by calling the billboard's corresponding set function, e.g., Billboard#setShow.

Example billboards

Performance:

Calling any get function, e.g., Billboard#getShow, is constant time. Calling a set function, e.g., Billboard#setShow, is constant time but results in CPU to GPU traffic when BillboardCollection#update is called. The per-billboard traffic is the same regardless of how many properties were updated. If most billboards in a collection need to be updated, it may be more efficient to clear the collection with BillboardCollection#removeAll and add new billboards instead of modifying each one.

Demo:

• Cesium Sandcastle Billboard Demo

See:

• BillboardCollection
• BillboardCollection#add
• Label

Source:

• /Source/Scene/Billboard.js

Methods

computeScreenSpacePosition

Computes the screen-space position of the billboard's origin, taking into account eye and pixel offsets. The screen space origin is the bottom, left corner of the canvas; x increases from left to right, and y increases from bottom to top.

Parameters:

Name	Type	Description
context	Context	The context.
frameState	FrameState	The same state object passed to BillboardCollection#update.

Throws:

• DeveloperError : Billboard must be in a collection.
• DeveloperError : context is required.
• DeveloperError : frameState is required.

Returns:

Cartesian2 The screen-space position of the billboard.

Example

console.log(b.computeScreenSpacePosition(scene.getContext(), scene.getFrameState()).toString());

See:

• Billboard#setEyeOffset
• Billboard#setPixelOffset

equals

Determines if this billboard equals another billboard. Billboards are equal if all their properties are equal. Billboards in different collections can be equal.

Parameters:

Name	Type	Description
other	Billboard	The billboard to compare for equality.

Returns:

Boolean true if the billboards are equal; otherwise, false.

getAlignedAxis

Gets the aligned axis in world space. The aligned axis is the unit vector that the billboard up vector points towards. The default is the zero vector, which means the billboard is aligned to the screen up vector.

Returns:

Cartesian3 The aligned axis.

See:

• Billboard#setRotation
• Billboard#getRotation
• Billboard#setAlignedAxis

getColor

Returns the color that is multiplied with the billboard's texture. The red, green, blue, and alpha values are indicated by the returned object's red, green, blue, and alpha properties, which range from 0 (no intensity) to 1.0 (full intensity).

Returns:

Number The color that is multiplied with the billboard's texture.

See:

• Billboard#setColor

getEyeOffset

Returns the 3D Cartesian offset applied to this billboard in eye coordinates.

Returns:

Cartesian3 The 3D Cartesian offset applied to this billboard in eye coordinates.

See:

• Billboard#setEyeOffset

getHeight

Gets the billboards custom height or undefined if the image height is used.

Returns:

Number The billboard's height or undefined.

See:

• Billboard#setHeight
• Billboard#getWidth
• Billboard#setWidth

getHorizontalOrigin

Returns the horizontal origin of this billboard.

Returns:

HorizontalOrigin The horizontal origin of this billboard.

See:

• Billboard#setHorizontalOrigin

getImageIndex

DOC_TBA

See:

• Billboard#setImageIndex
• BillboardCollection#setTextureAtlas

getPixelOffset

Returns the pixel offset from the origin of this billboard.

Returns:

Cartesian2 The pixel offset of this billboard.

See:

• Billboard#setPixelOffset

getPosition

Returns the Cartesian position of this billboard.

Returns:

Cartesian3 The Cartesian position of this billboard.

See:

• Billboard#setPosition

getRotation

Gets the rotation angle in radians.

Returns:

Number The rotation angle in radians.

See:

• Billboard#setRotation
• Billboard#getAlignedAxis
• Billboard#setAlignedAxis

getScale

Returns the uniform scale that is multiplied with the billboard's image size in pixels.

Returns:

Number The scale used to size the billboard.

See:

• Billboard#setScale

getShow

Returns true if this billboard will be shown. Call Billboard#setShow to hide or show a billboard, instead of removing it and re-adding it to the collection.

Returns:

Boolean true if this billboard will be shown; otherwise, false.

See:

• Billboard#setShow

getVerticalOrigin

Returns the vertical origin of this billboard.

Returns:

VerticalOrigin The vertical origin of this billboard.

See:

• Billboard#setVerticalOrigin

getWidth

Gets the billboards custom width or undefined if the image width is used.

Returns:

Number The billboard's width or undefined.

See:

• Billboard#setWidth
• Billboard#getHeight
• Billboard#setHeight

setAlignedAxis

Sets the aligned axis in world space. The aligned axis is the unit vector that the billboard up vector points towards. The default is the zero vector, which means the billboard is aligned to the screen up vector.

Parameters:

Name	Type	Description
value	Cartesian3	The aligned axis.

Throws:

DeveloperError : value is required.

Example

// Example 1.
// Have the billboard up vector point north
billboard.setAlignedAxis(Cartesian3.UNIT_Z);

// Example 2.
// Have the billboard point east.
billboard.setAlignedAxis(Cartesian3.UNIT_Z);
billboard.setRotation(-Cesium.Math.PI_OVER_TWO);

// Example 3.
// Reset the aligned axis
billboard.setAlignedAxis(Cartesian3.ZERO);

See:

• Billboard#setRotation
• Billboard#getRotation
• Billboard#setAlignedAxis

setColor

Sets the color that is multiplied with the billboard's texture. This has two common use cases. First, the same white texture may be used by many different billboards, each with a different color, to create colored billboards. Second, the color's alpha component can be used to make the billboard translucent as shown below. An alpha of 0.0 makes the billboard transparent, and 1.0 makes the billboard opaque.

default

alpha : 0.5

The red, green, blue, and alpha values are indicated by value's red, green, blue, and alpha properties as shown in Example 1. These components range from 0.0 (no intensity) to 1.0 (full intensity).

Parameters:

Name	Type	Description
value	Object	The color's red, green, blue, and alpha components.

Throws:

DeveloperError : value is required.

Example

// Example 1. Assign yellow.
b.setColor({
  red   : 1.0,
  green : 1.0,
  blue  : 0.0,
  alpha : 1.0
});

// Example 2. Make a billboard 50% translucent.
b.setColor({
  red   : 1.0,
  green : 1.0,
  blue  : 1.0,
  alpha : 0.5
});

See:

• Billboard#getColor

setEyeOffset

Sets the 3D Cartesian offset applied to this billboard in eye coordinates. Eye coordinates is a left-handed coordinate system, where x points towards the viewer's right, y points up, and z points into the screen. Eye coordinates use the same scale as world and model coordinates, which is typically meters.

An eye offset is commonly used to arrange multiple billboards or objects at the same position, e.g., to arrange a billboard above its corresponding 3D model.

value can be either a Cartesian3 or an object literal with x, y, and z properties. A copy of value is made, so changing it after calling setEyeOffset does not affect the billboard's eye offset; an explicit call to setEyeOffset is required.

Below, the billboard is positioned at the center of the Earth but an eye offset makes it always appear on top of the Earth regardless of the viewer's or Earth's orientation.

b.setEyeOffset({ x : 0.0, y : 8000000.0, z : 0.0 });

Parameters:

Name	Type	Description
value	Cartesian3	The 3D Cartesian offset in eye coordinates.

Throws:

DeveloperError : value is required.

See:

• Billboard#getEyeOffset

setHeight

Sets a custom height for the billboard. If undefined, the image height will be used.

Parameters:

Name	Type	Description
value	Number	The height of the billboard or undefined to use the image height.

See:

• Billboard#getHeight
• Billboard#getWidth
• Billboard#setWidth

setHorizontalOrigin

Sets the horizontal origin of this billboard, which determines if the billboard is to the left, center, or right of its position.

Parameters:

Name	Type	Description
value	HorizontalOrigin	The horizontal origin.

Throws:

DeveloperError : value is required.

Example

// Use a bottom, left origin
b.setHorizontalOrigin(HorizontalOrigin.LEFT);
b.setVerticalOrigin(VerticalOrigin.BOTTOM);

See:

• Billboard#getHorizontalOrigin
• Billboard#setVerticalOrigin

setImageIndex

DOC_TBA

See:

• Billboard#getImageIndex
• BillboardCollection#setTextureAtlas

setPixelOffset

Sets the pixel offset in screen space from the origin of this billboard. This is commonly used to align multiple billboards and labels at the same position, e.g., an image and text. The screen space origin is the bottom, left corner of the canvas; x increases from left to right, and y increases from bottom to top.

value can be either a Cartesian2 or an object literal with x and y properties. A copy of value is made, so changing it after calling setPixelOffset does not affect the billboard's pixel offset; an explicit call to setPixelOffset is required.

default

b.setPixelOffset({ x : 50, y : -25 });

The billboard's origin is indicated by the yellow point.

Parameters:

Name	Type	Description
value	Cartesian2	The 2D Cartesian pixel offset.

Throws:

DeveloperError : value is required.

See:

• Billboard#getPixelOffset
• Label#setPixelOffset

setPosition

Sets the Cartesian position of this billboard.

As shown in the examples, value can be either a Cartesian3 or an object literal with x, y, and z properties. A copy of value is made, so changing it after calling setPosition does not affect the billboard's position; an explicit call to setPosition is required.

Parameters:

Name	Type	Description
value	Cartesian3	The Cartesian position.

Throws:

DeveloperError : value is required.

Example

// Example 1. Set a billboard's position using a Cartesian3.
b.setPosition(new Cartesian3(1.0, 2.0, 3.0));

// Example 2. Set a billboard's position using an object literal.
b.setPosition({
  x : 1.0,
  y : 2.0,
  z : 3.0
});

See:

• Billboard#getPosition

setRotation

Sets the rotation angle in radians.

Parameters:

Name	Type	Description
value	Number	The rotation angle in radians.

Throws:

DeveloperError : value is required.

See:

• Billboard#getRotation
• Billboard#getAlignedAxis
• Billboard#setAlignedAxis

setScale

Sets the uniform scale that is multiplied with the billboard's image size in pixels. A scale of 1.0 does not change the size of the billboard; a scale greater than 1.0 enlarges the billboard; a positive scale less than 1.0 shrinks the billboard.

From left to right in the above image, the scales are 0.5, 1.0, and 2.0.

Parameters:

Name	Type	Description
value	Number	The scale used to size the billboard.

Throws:

DeveloperError : value is required.

See:

• Billboard#getScale
• Billboard#setImageIndex

setShow

Determines if this billboard will be shown. Call this to hide or show a billboard, instead of removing it and re-adding it to the collection.

Parameters:

Name	Type	Description
value	Boolean	Indicates if this billboard will be shown.

Throws:

DeveloperError : value is required.

See:

• Billboard#getShow

setVerticalOrigin

Sets the vertical origin of this billboard, which determines if the billboard is to the above, below, or at the center of its position.

Parameters:

Name	Type	Description
value	VerticalOrigin	The vertical origin.

Throws:

DeveloperError : value is required.

Example

// Use a bottom, left origin
b.setHorizontalOrigin(HorizontalOrigin.LEFT);
b.setVerticalOrigin(VerticalOrigin.BOTTOM);

See:

• Billboard#getVerticalOrigin
• Billboard#setHorizontalOrigin

setWidth

Sets a custom width for the billboard. If undefined, the image width will be used.

Parameters:

Name	Type	Description
value	Number	The width of the billboard or undefined to use the image width.

See:

• Billboard#getWidth
• Billboard#getHeight
• Billboard#setHeight