Expression
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new Cesium.Expression(expression, defines)
engine/Source/Scene/Expression.js 37

An expression for a style applied to a Cesium3DTileset.

Evaluates an expression defined using the 3D Tiles Styling language.

Implements the StyleExpression interface.

参数名称 类型 描述信息
expression string 可选 The expression defined using the 3D Tiles Styling language.
defines object 可选 Defines in the style.
使用示例s:
const expression = new Cesium.Expression('(regExp("^Chest").test(${County})) && (${YearBuilt} >= 1970)');
expression.evaluate(feature); // returns true or false depending on the feature's properties
const expression = new Cesium.Expression('(${Temperature} > 90) ? color("red") : color("white")');
expression.evaluateColor(feature, result); // returns a Cesium.Color object

成员(属性)

readonly expression : string
engine/Source/Scene/Expression.js 71

Gets the expression defined in the 3D Tiles Styling language.
默认值: undefined

方法

evaluate(feature, result) → boolean|number|string|RegExp|Cartesian2|Cartesian3|Cartesian4|Color
engine/Source/Scene/Expression.js 137

Evaluates the result of an expression, optionally using the provided feature's properties. If the result of the expression in the 3D Tiles Styling language is of type Boolean, Number, or String, the corresponding JavaScript primitive type will be returned. If the result is a RegExp, a Javascript RegExp object will be returned. If the result is a Cartesian2, Cartesian3, or Cartesian4, a Cartesian2, Cartesian3, or Cartesian4 object will be returned. If the result argument is a Color, the Cartesian4 value is converted to a Color and then returned.
参数名称 类型 描述信息
feature Cesium3DTileFeature The feature whose properties may be used as variables in the expression.
result object 可选 The object onto which to store the result.
返回值:
The result of evaluating the expression.

evaluateColor(feature, result) → Color
engine/Source/Scene/Expression.js 163

Evaluates the result of a Color expression, optionally using the provided feature's properties.

This is equivalent to Expression#evaluate but always returns a Color object.

参数名称 类型 描述信息
feature Cesium3DTileFeature The feature whose properties may be used as variables in the expression.
result Color 可选 The object in which to store the result
返回值:
The modified result parameter or a new Color instance if one was not provided.
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