Unity Playmaker VR XR - Trigger Particles when object thrown

In this Unity + Playmaker VR tutorial, I'll show adding grab intractable game object that you can throw and give feedback to the player with a particle system when hitting the target. ► Art Assets - Polygon City - Low Poly https://bit.ly/3ScOYa1 My discord link ► https://discord.gg/DgUdNDT7KU ► Do

A small moment of VR delight: wad up some paper, toss it at the trash can, and get rewarded with a particle celebration and a floating "+1". This tutorial covers the whole chain — a grabbable paper ball, an invisible trigger on the can, layered particle systems, and the four-action FSM that ties them together.

Make the paper throwable

The paper ball is a ProBuilder cube, subdivided and deformed until it reads as crumpled paper. Add an XR Grab Interactable — it brings a Rigidbody along — and keep use gravity on; a mass of 1 works, though lowering it would feel more paper-like. Enable smooth position and smooth rotation. Then, on both hand controllers, check hide controller on select: without it, picking up the ball shows the hand and the paper stacked in the same spot, and hiding the hand sells the illusion that you're holding the paper itself.

Build the invisible trigger

A ProBuilder cylinder sits across the trash can's opening. Turn off its Mesh Renderer — players never need to see it — but keep the mesh collider, with convex and is trigger both checked. Create a new tag called trashcan and assign it. That tag is what the paper's FSM will listen for.

Layer two particle systems

Inside the can, the main particle system pops particles upward: gravity modifier at 1 so they fall back down, emission around 100 (tune to taste), and a cone shape aimed out the top. Nested inside is a second system with a custom "+1" material, using a burst of exactly one instead of rate over time — a single score marker floating up amid the confetti. Together they give the player unmistakable feedback. Since the FSM will trigger them, uncheck play on awake behavior by deactivating the whole particle object so it starts off.

Wire the logic on the paper

Add an FSM to the paper ball with a detect trigger state containing a Trigger Event action — trigger events need a Rigidbody on one side, which the paper's grab component already provided. When the owner enters a trigger tagged trashcan, send a start particles event; add the transition and Ctrl-drag to a new play particles state. There, drag the particle system in and use Activate Game Object with activate checked — turning the object on plays the deactivated system. Then add Destroy Self from the action browser, placed after the activation, so the paper vanishes into the can. Test it in the headset: grab, throw, and the can erupts with a +1. One throw, instant feedback — the kind of detail that makes a VR scene feel alive.