🔥 VFX Workshop

What You'll Build

One tool, three different effects. Each exercise teaches a different combination of modules — by the end you'll have a mental map of which modules to reach for when you want a specific look.

Project Setup

1. 1
   Open Unity Hub → New Project → 3D (Core). Name it VFXWorkshop.
2. 2
   Create folders: Assets/Scripts, Assets/Effects, Assets/Materials.
3. 3
   Save the open scene as WorkshopScene.
4. 4
   Add a Plane at origin as a ground reference (GameObject → 3D Object → Plane). This makes effects easier to see.
5. 5
   Optional but recommended — set the scene's ambient to dark so glowing effects pop. Window → Rendering → Lighting → Environment tab → set Environment Lighting → Source to Color, then choose a dark grey/blue.

Anatomy of a Particle System

A Particle System is one component made of stacked modules. Each module is a section in the Inspector with a checkbox to enable/disable it. The first four modules below are always on — the rest are optional.

Create your first Particle System

1. 1
   Top menu → GameObject → Effects → Particle System. A white smoke-like effect appears, drifting upward.
2. 2
   Look at the Inspector — you'll see the Particle System component with multiple collapsible sections (modules). Click any header to expand/collapse it.
3. 3
   Notice the small floating Particle Effect panel at the bottom-right of the Scene view. This contains Pause, Restart, Stop, and Playback Time controls — use these instead of pressing Play to preview your effect.

Module Cheatsheet

You won't memorise these today. Skim now, then refer back during the exercises.

Always-on modules

Optional "Over Lifetime" modules

These modify a particle as it ages. Tick the checkbox next to the module name to enable.

Advanced modules (covered briefly later)

🔥 Build a Campfire

✨ Magic Pickup Glow

💥 One-Shot Explosion

Triggering Particles from a Script

The most common pattern: spawn an explosion (or any one-shot effect) at a location at runtime. Two approaches.

Approach A — Instantiate a prefab

Best when you want the effect at a specific position and you don't need to keep referencing it afterwards.

// ExplosionSpawner.cs
// ─────────────────────────────────────────────────────────────────────────────
// Press Space to spawn a copy of the Explosion prefab at a given position.
// Because the prefab's Stop Action is set to Destroy, the spawned copy
// removes itself from the scene after it finishes playing — no cleanup needed.
// ─────────────────────────────────────────────────────────────────────────────

using UnityEngine;

public class ExplosionSpawner : MonoBehaviour
{
    [SerializeField] private GameObject explosionPrefab;
    [SerializeField] private Transform  spawnPoint;

    void Update()
    {
        if (Input.GetKeyDown(KeyCode.Space))
        {
            if (explosionPrefab != null && spawnPoint != null)
                Instantiate(explosionPrefab, spawnPoint.position, Quaternion.identity);
        }
    }
}

Approach B — Call Play() on an existing system

Best when the effect lives on a specific GameObject (e.g. a gun's muzzle flash) and replays often.

// EffectTrigger.cs
// ─────────────────────────────────────────────────────────────────────────────
// Calls Play() on a referenced ParticleSystem when the player presses E.
// The ParticleSystem must have Play On Awake unticked.
// ─────────────────────────────────────────────────────────────────────────────

using UnityEngine;

public class EffectTrigger : MonoBehaviour
{
    [SerializeField] private ParticleSystem effect;

    void Update()
    {
        if (Input.GetKeyDown(KeyCode.E) && effect != null)
        {
            effect.Play();   // triggers the burst
            // effect.Stop();    // would stop emission
            // effect.Clear();   // would remove all live particles instantly
        }
    }
}

• Create an empty GameObject called Spawner. Attach ExplosionSpawner.cs.
• Drag the Explosion prefab from your Effects folder into the Explosion Prefab field in the Inspector.
• Drag the Spawner GameObject itself into the Spawn Point field (or use a separate empty GameObject as the spawn marker).
• Press Play. Press Space repeatedly — explosions spawn at the location you chose.

🎁 Real VFX Textures from the Asset Store

The default white particle squares look basic. Real games use textured sprites — actual flame shapes, smoke puffs, explosion frames. This section shows you how to grab a free pack and apply its textures to the Campfire and Explosion you already built.

Step 5A — Get Unity's Free Particle Pack

Unity Technologies publishes a free, official VFX pack with explosions, fire, smoke, sparks, and dust. It's the safest first pick.

1. 1
   Open your browser and go to https://assetstore.unity.com. Sign in with your Unity ID.
2. 2
   Search for "Particle Pack" by Unity Technologies. Click the asset.
3. 3
   Click the blue Add to My Assets button (it's free). When the dialog appears, click Open in Unity.
4. 4
   Unity opens the Package Manager. (If it doesn't: Window → Package Manager → Packages dropdown → My Assets.) Click Download, then Import. Leave all files ticked → click Import.
5. 5
   A new folder Assets/EffectExamples/ appears in the Project window with subfolders like Fire & Explosion Effects, Misc Effects, etc.

Step 5B — Two Ways to Use the Pack

Step 5C — Find a Texture in the Pack

1. 1
   In the Project window, navigate into Assets/EffectExamples. Browse the subfolders — each effect category has a Materials folder and a Textures folder.
2. 2
   Click any texture file (.png, .tga) to preview it in the Inspector. You're looking for: a soft white-on-black flame for the campfire, a circular explosion sprite or sprite sheet for the explosion.
3. 3
   Note: the existing materials in the pack may be configured for specific effects. The cleanest approach is to create your own material using their texture — that way you control the blending and tinting.

Step 5D — Apply a Real Flame Texture to your Campfire

1. 1
   Find a flame texture. In the Project window go to Assets/EffectExamples/Fire & Explosion Effects/Textures/. Look for a texture with "Fire", "Flame", or "Smoke" in the name. Click on a few to preview.
2. 2
   Create a new material. Right-click in your Assets/Materials folder → Create → Material. Name it Mat_Campfire.
3. 3
   Set the shader and blending. Select Mat_Campfire. In the Inspector at the top, click the Shader dropdown → Universal Render Pipeline → Particles → Unlit if you're on URP, or Particles → Standard Unlit if you're on Built-in (default).

4. 4
   Apply to the Campfire. Select the Campfire GameObject in your Hierarchy. In the Inspector, scroll down to the Renderer module of the Particle System (it's at the bottom). Drag Mat_Campfire from the Project window into the Material slot.
5. 5
   Tweak the look. The flame texture changes how the system renders. You may need to: increase Start Size (textured particles often look better at larger sizes), reduce Rate over Time (a texture has more visual weight than a flat dot — fewer particles needed), or pull back the Color over Lifetime alpha so trails are subtler.

Step 5E — Apply an Explosion Texture to your Explosion

Same workflow with one twist: explosion textures are often sprite sheets — a grid of frames meant to be played as an animation. Use the Texture Sheet Animation module to play through the frames.

1. 1
   Find an explosion sprite sheet. In Assets/EffectExamples look for a texture called something like Explosion_SpriteSheet or similar. It will look like a grid of explosion frames in the preview.
2. 2
   Note the grid size. Click the texture and look at it in the Inspector. Count the columns (Tiles X) and rows (Tiles Y). Common values: 4×4, 6×6, 8×8.
3. 3
   Create a new material. Same as the Campfire: Create → Material → name it Mat_Explosion → set Shader to Particles/Standard Unlit (Built-in) or URP equivalent → Blending Mode Additive. Drag the explosion sprite sheet into the Albedo / Base Map slot.
4. 4
   Apply to your Explosion prefab. Select the Explosion prefab in Assets/Effects → in the Particle System's Renderer module → drag Mat_Explosion into the Material slot.
5. 5
   Enable Texture Sheet Animation. In the Particle System Inspector, scroll to the Texture Sheet Animation module — tick its checkbox.

6. 6
   Test. Click the Restart button on the Scene view's Particle Effect panel. Each particle now plays through the full explosion animation as it lives — turning a flat blob into a real explosion frame sequence.
7. 7
   Tune for impact. Reduce Burst Count from 50 to 5–10 (textured frames are visually heavier — fewer is more). Increase Start Size to 1.0–2.0 so the texture is readable.

Common Asset Store VFX Pitfalls

Common Problems

Extension Challenges

📚 Required Readings

Two scholarly articles accompany this week's practical work. They build the theoretical side of game development — how researchers analyse and critique games as media. Read both before next week's session.