这里HD Live Map Layers

这里HD Live Map¹(HERE HDLM), developed by HERE Technologies, is a cloud-based web service that enables you to access highly accurate, continuously updated map data. The data is composed of tiled map layers containing information such as the topology and geometry of roads and lanes, road-level and lane-level attributes, and the barriers, signs, and poles found along roads. The data is stored in a series of map catalogs that correspond to geographic regions.

To access layer data for a selection of map tiles, use ahereHDLMReaderobject. For information on thehereHDLMReaderworkflow, seeRead and Visualize HERE HD Live Map Data.

The layers are grouped into these models:

Road Centerline Model— Provides road topology, shape geometry, and other road-level attributes
高清车道模型— Contains lane topology, highly accurate geometry, and lane-level attributes
HD Localization Model- 包括多个功能，例如路标，以支持本地化策略万博1manbetx

从这里的瓷砖访问高清实时地图目录的图层

The available layers vary by geographic region, so not all layers are available for every map tile. When you call the读function on ahereHDLMReaderobject and specify a map layer name, the function returns the layer data as an object. For more information about these layer objects, see the读function reference page.

Road Centerline Model

The Road Centerline Model represents the topology of the road network. It is composed of链接corresponding to streets andnodes对应于十字路口和死胡同。对于每个地图瓷砖，此模型中的层包含有关这些链接和节点的信息，例如道路网络的2-D线几何形状，速度属性和路由属性。

The figure shows a plot for the拓扑几何图层，可视化节点和链接的2-D线几何形状。

拓扑几何layer with boundaries, nodes, and links

This table shows the map layers of the Road Centerline Model that ahereHDLMReader对象可以读取。

Road Centerline Model Layers	Description
`拓扑几何`	道路的拓扑和二维线几何形状。该层还包含地图瓷砖中链接（街道）和节点（交叉点和死端）的定义。
`RoutingAttributes`	Road attributes related to navigation and conditions. These attributes are mapped parametrically to the 2-D polyline geometry in the topology layer.
`路由划分`	Core navigation lane attributes and conditions, such as the number of lanes in a road. These values are mapped parametrically to 2-D polylines along the road links.
`SpeedAttributes`	Speed-related road attributes, such as speed limits. These attributes are mapped to the 2-D polyline geometry of the topology layer.
`AdasAttributes`	精确的几何测量值，例如道路的坡度，高程和曲率。使用此数据来开发高级驱动程序辅助系统（ADA）。
`外部重新加工`	对其他地图的外部链接，节点和拓扑的引用。
`LaneRoadReferences`（也是高清车道模型的一部分）	道路和车道集团参考和范围信息。使用此数据在道路中心线模型和高清车道模型之间转换位置。

高清车道模型

The HD Lane Model represents the topology and geometry oflane groups，这是链接（街道）中的车道。在此模型中，车道的形状以2-D和3-D位置进行建模，并支撑厘米级的精度。万博1manbetx该模型提供了多个车道属性，包括车道类型，行进方向以及车道边界颜色和样式。

The figure shows a plot for the融合学图层对象，可视化泳道组及其连接器在地图瓷砖中的2D线几何形状。

带有边界，车道组连接器和车道组的灯笼学层

This table shows the map layers of the HD Lane Model that ahereHDLMReader对象可以读取。

高清车道模型Layers	Description
`融合学`	高清车道模型的拓扑，包括车道集团，车道组连接器，车道和车道连接器拓扑。该层还包含了泳道模型的简化2-D边界几何形状，用于确定地图图块的亲和力和溢出。
`LaneGeometryPolyline`	3-D lane geometry composed of a set of 3-D points joined into polylines.
`laneattributes`	Lane-level attributes, such as direction of travel and lane type.
`LaneRoadReferences`(also part of Road Centerline Model)	道路和车道集团参考和范围信息。Used to translate positions between the Road Centerline Model and the HD Lane Model.

HD Localization Model

高清本地化模型包含数据，例如交通标志，障碍物和电线杆，可帮助自动驾驶汽车准确地定位它们在道路网络中的位置。

This table shows the map layers of the HD Localization Model that ahereHDLMReader对象可以读取。读者不支持此层数据的可视化。万博1manbetx

HD Localization Model Layers	Description
`LocalizationBarrier`	Positions, dimensions, and attributes of barriers such as guardrails and Jersey barriers found along roads
`定位杆`	Positions, dimensions, and attributes of traffic signal poles and other poles found along or hanging over roads
`本地化`	Positions, dimensions, and attributes of traffic-sign faces found along roads