[Home](./index.md) > [@three3d/effect](./effect.md) > [BandGeometry](./effect.bandgeometry.md) ## BandGeometry class 带状几何体 **Signature:** ```typescript export declare class BandGeometry extends PathGeometry ``` **Extends:** [PathGeometry](./effect.pathgeometry.md)<[BandGeometryOptions](./effect.bandgeometryoptions.md)> ## Remarks 可根据曲线、折线点来生成带状几何体； 支持路径追加； 支持设置起始长度 支持起始-终点颜色渐变 支持绘制的指定的长度区间 支持设置宽度 支持设置带状几何体起始位置处的向上方向 ## Constructors | Constructor | Modifiers | Description | | --- | --- | --- | | [(constructor)(options)](./effect.bandgeometry._constructor_.md) | | Constructs a new instance of the BandGeometry class | ## Properties | Property | Modifiers | Type | Description | | --- | --- | --- | --- | | [connectionType](./effect.bandgeometry.connectiontype.md) | | LineConnectionType | 线的衔接类型 | | [drawType](./effect.bandgeometry.drawtype.md) | | [PathDrawType](./effect.pathdrawtype.md) | CurvePath 的绘制类型 | | [fixUp](./effect.bandgeometry.fixup.md) | | boolean | 是否固定 up；保证up不变 | | [frenetFrames](./effect.bandgeometry.frenetframes.md) | | Point\_Length\_FrenetFrames \| null | | | [geometryData](./effect.bandgeometry.geometrydata.md) | readonly | { position: number\[\]; normal: number\[\]; uv: number\[\]; index: number\[\]; color: number\[\]; lineDistance: number\[\]; lengths: number\[\]; points: Vector3\[\]; tangents: Vector3\[\]; normals: Vector3\[\]; binormals: Vector3\[\]; } \| null | 几何体的数据 | | [isBandGeometry](./effect.bandgeometry.isbandgeometry.md) | readonly | (not declared) | | | [openedGeometryData](./effect.bandgeometry.openedgeometrydata.md) | readonly | [BandGeometryData](./effect.bandgeometrydata.md) \| null | 未闭合的几何体的数据 | | [options](./effect.bandgeometry.options.md) | static | [BandGeometryOptions](./effect.bandgeometryoptions.md) | | | [smoothStepAngle](./effect.bandgeometry.smoothstepangle.md) | | number \| undefined | 圆形衔接角的步长角 | | [smoothStepLength](./effect.bandgeometry.smoothsteplength.md) | | number \| undefined | 圆形衔接角的长度步长 | | [up](./effect.bandgeometry.up.md) | | IVector3 | 起点处的向上的方向 { x: 0, y: 1, z: 0 } | | [useU](./effect.bandgeometry.useu.md) | | boolean | 是否固定 up；保证up不变 | | [uvStep](./effect.bandgeometry.uvstep.md) | | number | uv的步长 | ## Methods | Method | Modifiers | Description | | --- | --- | --- | | [append(pathItem)](./effect.bandgeometry.append.md) | | | | [getDivisionIndex(vertexIndex)](./effect.bandgeometry.getdivisionindex.md) | | 获取顶点索引对应的分段索引 | | [resetAttributes(attrs)](./effect.bandgeometry.resetattributes.md) | | 重围所有的 Attributes | | [setDrawLength(startLength, endLength)](./effect.bandgeometry.setdrawlength.md) | | 设置绘制的长度范围 | | [updateGeometry()](./effect.bandgeometry.updategeometry.md) | | |