In road navigation applications, thematic maps are often used to express road conditions such as smooth flow and congestion. Green indicates smooth flow, yellow indicates slow traffic, and red indicates congestion. When viewing the map at a larger map scale, main roads, auxiliary roads, and ramps are usually displayed separately. Based on the congestion data of roads, select fields to create a unique value thematic map. At a smaller scale, roads are generally displayed as bidirectional, without showing the conditions of auxiliary roads and ramps, only displaying congestion in both directions of main roads. To avoid overlapping of road lines at a small scale, road lines need to be offset.

This example is based on NAVINFO data and details how to create real-time road condition maps. The case applies to NAVINFO data. The specific content of this case includes the following two parts:

• Creating Traffic Condition Maps: Introduces how to create traffic condition maps.
• Traffic Line Correction: Introduces how to correct the digitization direction of road lines.