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Label

Label

new

A Label draws viewport-aligned text positioned in the 3D scene. This constructor should not be used directly, instead create labels by calling LabelCollection#add.

Throws:
  • DeveloperError : translucencyByDistance.far must be greater than translucencyByDistance.near
  • DeveloperError : pixelOffsetScaleByDistance.far must be greater than pixelOffsetScaleByDistance.near
Demo:
See:
Source:

Members

:Cartesian3

Gest and sets the 3D Cartesian offset applied to this label 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 label or objects at the same position, e.g., to arrange a label above its corresponding 3D model.

Below, the label 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.

l.eyeOffset = new Cartesian3(0.0, 8000000.0, 0.0);

:Color

Gets and sets the fill color of this label.
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:String

Gets and sets the font used to draw this label. Fonts are specified using the same syntax as the CSS 'font' property.
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:HorizontalOrigin

Gets and sets the horizontal origin of this label, which determines if the label is drawn to the left, center, or right of its position.


Example
// Use a top, right origin
l.horizontalOrigin = Cesium.HorizontalOrigin.RIGHT;
l.verticalOrigin = Cesium.VerticalOrigin.TOP;

:Object

Gets or sets the user-defined object returned when the label is picked.

:Color

Gets and sets the outline color of this label.
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:Number

Gets and sets the outline width of this label.
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:Cartesian2

Gets and sets the pixel offset in screen space from the origin of this label. This is commonly used to align multiple labels and billboards 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.

default
 l.pixeloffset = new Cartesian2(25, -75);
The label's origin is indicated by the yellow point.

:NearFarScalar

Gets and sets near and far pixel offset scaling properties of a Label based on the Label's distance from the camera. A label's pixel offset will be scaled between the NearFarScalar#nearValue and NearFarScalar#farValue while the camera distance falls within the upper and lower bounds of the specified NearFarScalar#near and NearFarScalar#far. Outside of these ranges the label's pixel offset scaling remains clamped to the nearest bound. If undefined, pixelOffsetScaleByDistance will be disabled.
Example
// Example 1.
// Set a label's pixel offset scale to 0.0 when the
// camera is 1500 meters from the label and scale pixel offset to 10.0 pixels
// in the y direction the camera distance approaches 8.0e6 meters.
text.pixelOffset = new Cesium.Cartesian2(0.0, 1.0);
text.pixelOffsetScaleByDistance = new Cesium.NearFarScalar(1.5e2, 0.0, 8.0e6, 10.0);

// Example 2.
// disable pixel offset by distance
text.pixelOffsetScaleByDistance = undefined;

:Cartesian3

Gets and sets the Cartesian position of this label.

:Number

Gets and sets the uniform scale that is multiplied with the label's size in pixels. A scale of 1.0 does not change the size of the label; a scale greater than 1.0 enlarges the label; a positive scale less than 1.0 shrinks the label.

Applying a large scale value may pixelate the label. To make text larger without pixelation, use a larger font size when calling Label#font instead.


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

:Boolean

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

:LabelStyle

Gets and sets the style of this label.

:String

Gets and sets the text of this label.

:NearFarScalar

Gets and sets near and far translucency properties of a Label based on the Label's distance from the camera. A label's translucency will interpolate between the NearFarScalar#nearValue and NearFarScalar#farValue while the camera distance falls within the upper and lower bounds of the specified NearFarScalar#near and NearFarScalar#far. Outside of these ranges the label's translucency remains clamped to the nearest bound. If undefined, translucencyByDistance will be disabled.
Example
// Example 1.
// Set a label's translucencyByDistance to 1.0 when the
// camera is 1500 meters from the label and disappear as
// the camera distance approaches 8.0e6 meters.
text.translucencyByDistance = new Cesium.NearFarScalar(1.5e2, 1.0, 8.0e6, 0.0);

// Example 2.
// disable translucency by distance
text.translucencyByDistance = undefined;

:VerticalOrigin

Gets and sets the vertical origin of this label, which determines if the label is to the above, below, or at the center of its position.


Example
// Use a top, right origin
l.horizontalOrigin = Cesium.HorizontalOrigin.RIGHT;
l.verticalOrigin = Cesium.VerticalOrigin.TOP;

Methods

Computes the screen-space position of the label'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 LabelCollection#update.
Returns:
Cartesian2 The screen-space position of the label.
Example
console.log(l.computeScreenSpacePosition(scene).toString());
See:

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

Parameters:
Name Type Description
other Label The label to compare for equality.
Returns:
Boolean true if the labels are equal; otherwise, false.

Returns true if this object was destroyed; otherwise, false.

If this object was destroyed, it should not be used; calling any function other than isDestroyed will result in a DeveloperError exception.

Returns:
Boolean True if this object was destroyed; otherwise, false.