Automating Connections

One powerful feature of PathEngine's '2D content processing' functionality is the possibility for automatic connection between separate ground meshes.
This makes it possible to set up content pieces, such as buildings, so that they can be moved around within the world, with the connection between those pieces and each other, and the rest of the world generated automatically by PathEngine.

Two types of automatic connections are supported:
Connections between building entrances and the ground on which they are placed, and connections between matching pairs of edges.
Details about each kind of connection can be found in Building Entrance Connections, and Matching Edge Connections (in the Programmers Guide).

Both connection types work in terms of marking faces in the source geometry to indicate things like 'building entrance portals', 'matching edge markers', and 'building external shapes'.
The content-platform specific documentation provides details about exactly how to mark faces in this way.

Automatic connections are essential in a two-stage content process, because any direct connection between the pieces of ground in separate chunks (or between chunks and base terrain) must be expressed in terms of these automatic connections, but are also very important when working with any significant amount of geometry in a single-stage content process, because they enable markup geometry to be instanced within a single scene, and make it easier to subsequently modify the scene.

Building external shapes as generalised 'cookie cutter'

Starting from release 5.19, the 'building entrance connection' mechanism no longer requires internal ground at building entrance portals, making it possible to apply building external shapes as a kind of generalised cookie cutter for cutting arbitrary non-convex regions out of the ground mesh result.

Optimising the resulting mesh

When using automatic connection at building connections, it is a good idea to also turn on the external edge optimisation, to avoid a lot of nearly inline external vertices potentially being created by the boolean subtraction applied for the building external shapes.
Refer to the UI overviews in the content-application specific documentation for details about setting this option.

Importing example geometry

A quick way to get a worked example of geometry set up for automatic connections is to import the content processing or content chunk example geometry.