Speaker A
In this video, we're going to be covering spawners. Aaand... done.
Learn how to build a scalable, flexible enemy spawner system in Godot that improves performance and game design.
Ask about this video. Answers come from its transcript only — with the timestamp, so you can check them.
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Key Takeaways
- Using spawners improves game performance by only processing enemies when necessary.
- A good spawner manages the entire lifecycle of enemies, including spawning, despawning, and respawning.
- Flexibility and scalability are crucial for spawner design to accommodate different enemy behaviors.
- Editor tools like live previews enhance usability and speed up development.
- Refactoring and balancing code quality with practical functionality is important in game development.
What the video covers
- Introduction to the need for a scalable and reliable enemy spawning system in Godot.
- Problems with placing enemies directly in levels and how it affects performance.
- Overview of a simple spawner setup using Marker2D, VisibleOnScreenNotifier2D, and Timer nodes.
- Demonstration of spawning enemies via spawners instead of direct placement.
- Explanation of different spawn behaviors like respawning on screen re-entry or timed random delays.
- Editor integration with tool scripts for live preview and fallback sprites.
- Acknowledgement of initial code imperfections and the importance of balancing perfection with practicality.
- Discussion on the lifecycle management of spawned enemies and performance considerations.
- Key questions a good spawner must answer regarding spawn timing, location, and rules.
- Mention of the need for a global system to manage multiple spawners, though not implemented here.
Chapters
- 00:00Introduction to Spawners
- 00:36Setting the Goal for a Reliable Spawner
- 01:08Why Direct Enemy Placement is Problematic
- 01:58Building a Scalable Spawning System
- 02:23Components of the Spawner Node
- 03:12Spawner in Action: Assigning Enemies
- 04:02Different Spawn Behaviors Explained
- 05:02Testing and Preview Features in the Editor
- 05:52Assessing the Initial Spawner Code
- 06:23Balancing Code Quality and Practicality
Full Transcript — Download SRT & Markdown
Speaker A
So, today we're going to build a proper spawning system. We're going to be looking at how to... Oh, okay.
Speaker A
Well, I can probably fix that. Oh, no. Uh, in this video, we're going to be looking at how to
Speaker A
build a scalable spawning system. Hang on. I... I turned it off. Why? Why? Why is it still?
Speaker A
We need a spawning system that's reliable, easy to extend, and won't cause problems later. So,
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let's get started. If you're dropping enemies directly into a level, they're still moving,
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still processing, whether or not the player is even nearby. That might be fine at first,
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but as your game grows, that starts to become a problem. So, today we're going to build a
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spawning system that's designed to scale. In my first project, I built a spawner pretty early on.
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And honestly, it did its job. It handled the behaviors I needed. It was flexible enough,
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and it let me move fast. But now, I want to take that idea and turn it into something I can reuse
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anywhere. The spawner itself is simple. There's just a Marker2D, a VisibleOnScreenNotifier2D,
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and a Timer. A Node2D could have been used as the root here, but Marker2D is essentially the
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same thing. It just adds a visual gizmo to the editor to make visualizing it a bit easier.
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It's the way that these pieces work together that makes the magic happen. So, let's see it in
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action. Instead of placing an enemy directly in the level, I drag in a spawner. Then,
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I just assign what it should spawn. Now, the enemy doesn't exist until the spawner decides it should.
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And the options in the editor allow me to tune the spawn behavior. This Telly behaves like a standard
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enemy. It respawns when it's defeated, but only after the spawner comes back on screen. These
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Spikers use a completely different rule set. They spawn on a timer with a random delay. Triggered
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when they die or leave the screen. Hmm... These are a little hard to see here. I wonder if
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there's a spot that's a little more open. I've never actually checked up here. Oh, perfect.
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It's almost like this room was made for testing spawners. In here, we can clearly see the respawn
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behavior of the Spiker. If I want, I can change the enemy type. And because it's a tool script,
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the preview updates in the editor. I even added a fallback sprite if it can't find the preview.
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Overall, this works. It gives me flexible spawning behavior. It's easy to use,
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and it solved the problem I had at the time. But by now, you may have spotted a bit of a problem.
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There are a few things to clean up, but let's take a quick look under the hood. Warts and all.
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That is one big pile of s- Okay, maybe warts and all wasn't the best idea, but to be fair,
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every experienced developer has code like this somewhere. It may not be pretty,
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but it worked. It's important to remember that your time is valuable, and chasing perfection at
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the cost of "good enough" usually is not worth it as long as you're taking performance into account.
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This solved the problem it was written for at the time, but in order to bring it forward,
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it's going to need to do more. So now refactoring makes sense. So, while past
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me goes off to clean this up, future me can talk about what a good spawner actually needs to do.
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Spawning is not just "instantiate an enemy." First, it's about managing its entire
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lifecycle. When does it exist? When should it stop existing? When is it allowed to come back? Second,
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it's about performance. Making sure things aren't running when they shouldn't be. And finally, it's
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about game rules. What happens if an enemy leaves the screen? What if you want an ambush? What
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if multiple spawners share a limit? What about hazards that need to keep moving, even off screen?
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So, a good spawner needs to answer a few key questions. What do I spawn? Where do I spawn it?
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When am I allowed to spawn it? Do I already have something else active? What happens when it dies
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or disappears? And what rules control all of that? Each spawner should handle its own local logic,
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but eventually we'll also want something higher level. A global system that can enforce limits,
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coordinate behavior, and clean things up when the entire section unloads. We won't build that
Topics:Godotenemy spawnergame developmentscalable spawning systemgame performanceMarker2DVisibleOnScreenNotifier2DTimertool scriptgame design
