Values and type information for per-instance geometry attributes.
| Name | Type | Description | ||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
options |
object |
Object with the following properties:
|
Throws:
-
DeveloperError : options.componentsPerAttribute must be between 1 and 4.
Example:
const instance = new Cesium.GeometryInstance({
geometry : Cesium.BoxGeometry.fromDimensions({
dimensions : new Cesium.Cartesian3(1000000.0, 1000000.0, 500000.0)
}),
modelMatrix : Cesium.Matrix4.multiplyByTranslation(Cesium.Transforms.eastNorthUpToFixedFrame(
Cesium.Cartesian3.fromDegrees(0.0, 0.0)), new Cesium.Cartesian3(0.0, 0.0, 1000000.0), new Cesium.Matrix4()),
id : 'box',
attributes : {
color : new Cesium.GeometryInstanceAttribute({
componentDatatype : Cesium.ComponentDatatype.UNSIGNED_BYTE,
componentsPerAttribute : 4,
normalize : true,
value : [255, 255, 0, 255]
})
}
});See:
Members
componentDatatype : ComponentDatatype
The datatype of each component in the attribute, e.g., individual elements in
GeometryInstanceAttribute#value.
A number between 1 and 4 that defines the number of components in an attributes.
For example, a position attribute with x, y, and z components would have 3 as
shown in the code example.
Example:
show : new Cesium.GeometryInstanceAttribute({
componentDatatype : Cesium.ComponentDatatype.UNSIGNED_BYTE,
componentsPerAttribute : 1,
normalize : true,
value : [1.0]
})
When
true and componentDatatype is an integer format,
indicate that the components should be mapped to the range [0, 1] (unsigned)
or [-1, 1] (signed) when they are accessed as floating-point for rendering.
This is commonly used when storing colors using ComponentDatatype.UNSIGNED_BYTE.
-
Default Value:
false
Example:
attribute.componentDatatype = Cesium.ComponentDatatype.UNSIGNED_BYTE;
attribute.componentsPerAttribute = 4;
attribute.normalize = true;
attribute.value = [
Cesium.Color.floatToByte(color.red),
Cesium.Color.floatToByte(color.green),
Cesium.Color.floatToByte(color.blue),
Cesium.Color.floatToByte(color.alpha)
];
The values for the attributes stored in a typed array. In the code example,
every three elements in
values defines one attributes since
componentsPerAttribute is 3.
Example:
show : new Cesium.GeometryInstanceAttribute({
componentDatatype : Cesium.ComponentDatatype.UNSIGNED_BYTE,
componentsPerAttribute : 1,
normalize : true,
value : [1.0]
})