Using NavLinks for Non-Linear Movement

In this lesson, you will learn how to bridge disconnected Navigation Mesh surfaces using Navigation Links to enable your AI to perform jumps, drops, or ladder climbs.

Bridging the Gap

By default, the NavMesh acts like a flat plane; if there is a gap between two surfaces, your AI pathfinding will fail because it cannot find a continuous path across the void. Navigation Links—specifically the NavLinkProxy actor—act as a "portal" or "manual connection" that tells the AI, "You can jump across this gap to reach that surface."

When you place a NavLinkProxy in your level, it creates two points connected by a segment. When the AI's pathfinding system detects this link, it treats it as a valid path, allowing the agent to transition from one NavMesh island to another.

Implementing the Jump Logic

To make the AI actually perform the jump rather than just "teleporting" across, you must handle the logic inside the NavLinkProxy blueprint. By default, the actor exposes an OnSmartLinkReached event. You can trigger this when the AI arrives at the start point:

// Within your NavLinkProxy Blueprint
Event OnSmartLinkReached(AActor* Agent, FVector Destination)
{
    // 1. Cast Agent to your AI Character
    // 2. Play the Jump or Climb Animation Montage
    // 3. Move the AI toward the Destination vector
}

The AI controller simply sees the link as a node in the path. Once it reaches the start point of the link, it pauses movement and fires the event. You then gain full control to trigger the specific Motion Warping or Root Motion animations you’ve previously refined to ensure the character lands accurately on the target platform.

Why This Matters

Using NavLinks keeps your navigation memory-efficient. Instead of trying to force the NavMesh to generate over complex, non-walkable geometry (like climbing a vertical ladder), you use these links to explicitly tell the AI where non-linear movement is allowed. This gives you precise control over how your characters navigate the verticality of your levels, ensuring they don't just walk off ledges, but actively interact with the environment.

Key Takeaway: Navigation Links convert spatial gaps into traversable paths, allowing you to trigger custom animations that bridge disconnected NavMesh surfaces for fluid, non-linear AI movement.