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Contents, Tools, Max Exporter, Placing obstacles

Placing obstacles

The exporter enables you to place obstacles as shapes pinned to the surface of the ground mesh, as an alternative to physically cutting shapes out of the mesh.
The advantage of placing shapes in this way is that the shapes can be moved around later more easily and without affecting the underlying mesh.
See Anchors and Pinned Shapes for general information about pinned shapes.

How obstacles are set up

Objects used to define obstacle shapes must be convertible by Max to a 'Linear Shape'. The resulting linear shape must have a single, closed 'polyline' with at least three vertices.
You can use the NGon primitive, for example, on the create tab, shapes subsection.
(Make sure that 'Adaptive' is turned off, and 'Optimize' is turned on, in the 'Interpolation' roll-out, so that 3DS Max doesn't subdivide the shape's line segments.)

Shapes are identified by a name prefixed and linked directly underneath an anchor.
(The anchor under which a shape is linked is the anchor that will be used to 'pin' that shape to the ground mesh.)

Name prefixes

Shapes with names beginning with 'baseObstacle_' are treated as base obstacles.
Shapes with names beginning with 'obstacle_' are treated as named obstacles.

Base obstacles are obstacles that are effectively 'burnt in' to the base mesh, and that will always apply to pathfinding. Named obstacles, on the other hand, essentially record information about potential object placement that can be looked up against the mesh at run-time.
(So note that you won't actually see named obstacles when loading up a 'vanilla' testbed application that doesn't include code to explicitly look these up and display them.)

For base obstacles, the remainder of the name is irrelevant but for named obstacles this is used to identify the obstacle and must correspond with the string used to later retrieve this in game.
e.g. 'obstacle_door0_closed' identifies an obstacle that can be retrieved in game with the string 'door0_closed'.

For backwards compatibility, the prefix 'shape_' is recognised.
Shapes beginning with this prefix are treated as base obstacles.
(But note that this prefix is depreciated and may be unsupported in a future version.)
Shapes marked with other prefixes are ignored.


As with anchors, example geometry can be obtained by importing the relevant example, from this page, or levels from the playable demo.

Documentation for PathEngine release 6.04 - Copyright © 2002-2024 PathEnginenext: Surface types