The minimap in Bus Simulator 21 in basically a camera following the player from a distance, which only renders specific assets which are hidden to the main camera.
All points of interest, buses, drivers have already a representation child blueprint that takes care of the minimap, when they are placed in the map or spawn during gameplay they automatically spawn.
For the street representation we will need to generate a simplified mesh for the road network, that we can use in the minimap.
Make sure you fulfill the Houdini prerequisites before your start here:
Search for the RoadForMinimap Houdini asset, an place it in the scene
Make sure to move the material to 0,0,0 in the world
In the Houdini Inputs section click on Start Selection
Select the RoadNetworkEditorActor in the world outliner
Click on Use Current Selection button. This should automatically trigger the generation of the mesh.
Once the mesh is generated you can delete the road for minimap asset again from the scene. The mesh has been createdn and stored in the RoadforMinimap folder in your mod map plugin
Search for the BP_WorldAssetRepresentation_Street in the project and place it in the scene
Again make sure to place it at 0,0,0
Select the representation in the oultliner and then select the mesh child in the blueprint.
Set the static mesh variable on the mesh to the newly created RoadforMinimap mesh.
You will not directly see a difference as the mesh in the representation is hidden by default, it will be automatically activated once the game runs.
The camera in the map menu can be freely moved and tries to be a constant distance from the ground. We are constantly tracing against the ground to determine how
far away the camera is.
Any terrain or other object that should influence how the camera moves needs to block the Terrain Trace Responses, Check the DummyGeometry Cube in the provided Mod Map.