Arguably, more fun than writing code is removing code. I was assembling a split-screen multiplayer UI.
The goal behavior is to show/hide the appropriate displays for the players, depending on how many players there are.
Initially, the code to update the UI was very simple, because I started with two players. In that case, you can get away with just toggling the visibility of the second player’s display.
Once I added more scenarios, the code got lengthier. In order to support 0 – 4 players correctly, it ended up looking like this:
## Show the correct viewports based on player countfunc_update_player_viewports():match num_players:0:%HBTop.visible=false%HBBottom.visible=false1:%HBTop.visible=true%HBTop/VPC1.visible=true%HBTop/VPC2.visible=false%HBBottom.visible=false2:%HBTop.visible=true%HBTop/VPC1.visible=true%HBTop/VPC2.visible=true%HBBottom.visible=false3:%HBTop.visible=true%HBTop/VPC1.visible=true%HBTop/VPC2.visible=true%HBBottom.visible=true%HBBottom/VPC1.visible=true%HBBottom/VPC2.visible=false4:%HBTop.visible=true%HBTop/VPC1.visible=true%HBTop/VPC2.visible=true%HBBottom.visible=true%HBBottom/VPC1.visible=true%HBBottom/VPC2.visible=true
If you’re familiar with the match statement syntax, this code is really quite straightforward. It’s a bit naïve verbose, but it is easy to follow and structured enough to be readable. But could it be shorter? The cases for three and four players look nearly identical.
Sometimes it can be risky to refactor something verbose for a bit more brevity. Some solutions might end up being “too clever”. I try to aim for clarity first unless there are specific performance demands.
Usually, it’s a matter of how to approach the problem. The code above very clearly divides up the use cases. If I’m dealing with three players, I know I need to look at the
3:
block and that I can ignore the other blocks of code. It’s very light in terms of cognitive load.
This code snippet achieves that same behavior, but in only 8 lines of code instead of 30:
## Show the correct viewports based on player countfunc_update_player_viewports():%HBTop.visible= num_players >0%HBTop/VPC1.visible= num_players >0%HBTop/VPC2.visible= num_players >1%HBBottom.visible= num_players >2%HBBottom/VPC1.visible= num_players >2%HBBottom/VPC2.visible= num_players >3
But is it as intuitive?
The match statement is entirely gone.
Each node is updated exactly once (but with a boolean expression instead of a boolean constant; arguably less declarative and needs computation by the reader).
The order of nodes is specified so that the visibility is
true
until it’s
false
. Example for 2 players:
## Update the viewports to reflect the configured playersfunc_update_player_viewports():%HBTop.visible= num_players >0%HBTop/VPC1.visible= num_players >0%HBTop/VPC2.visible= num_players >1%HBBottom.visible= num_players >2%HBBottom/VPC1.visible= num_players >2%HBBottom/VPC2.visible= num_players >3
Well, it’s shorter anyway.
One final touch: I want to always show the first viewport, even when there are no players:
## Show the correct viewports based on player countfunc_update_player_viewports():%HBTop.visible= num_players >=0%HBTop/VPC1.visible= num_players >=0%HBTop/VPC2.visible= num_players >1%HBBottom.visible= num_players >2%HBBottom/VPC1.visible= num_players >2%HBBottom/VPC2.visible= num_players >3
Just a couple of days ago, Godot 4.0 alpha 17 was announced. Today, Godot Engine 4.0 beta 1 was released. Be sure to check out the announcement. There are lots of improvements across the board; rendering, lighting, physics and navigation, animation, and scripting.
Godot Engine is an open-source game engine. With the 4.0 release on the horizon, it’ll gain quite a bit of attention. And it’s an engine worth keeping an eye on. Internet Gaming. Serious business. Game development is serious business. The global gaming market size was 203 billion USD in 2020 (per fortunebusinessinsights). It is predicted …
Here’s a collection of tutorials that are helpful if you’re new to using Control and Container nodes to create UIs in Godot 4. The Game Dev Artisan video covers creating a simple UI with a reload indicator for a simple 2D tank game: Clear Code’s 11+ hour Ultimate Introduction to Godot 4 has a chapter …
Normally I use OBS for screen recording, but there are cases where it makes sense to use Godot’s built-in movie writer that was recently announced. For example, if you have a slow PC or really demanding game, OBS will skip frames. It makes sense since OBS is just recording what’s on the screen in real …
A GDScript refactoring exercise
Arguably, more fun than writing code is removing code. I was assembling a split-screen multiplayer UI.
The goal behavior is to show/hide the appropriate displays for the players, depending on how many players there are.
Initially, the code to update the UI was very simple, because I started with two players. In that case, you can get away with just toggling the visibility of the second player’s display.
Once I added more scenarios, the code got lengthier. In order to support 0 – 4 players correctly, it ended up looking like this:
If you’re familiar with the match statement syntax, this code is really quite straightforward. It’s a bit naïve verbose, but it is easy to follow and structured enough to be readable. But could it be shorter? The cases for three and four players look nearly identical.
Sometimes it can be risky to refactor something verbose for a bit more brevity. Some solutions might end up being “too clever”. I try to aim for clarity first unless there are specific performance demands.
Usually, it’s a matter of how to approach the problem. The code above very clearly divides up the use cases. If I’m dealing with three players, I know I need to look at the
3:
block and that I can ignore the other blocks of code. It’s very light in terms of cognitive load.This code snippet achieves that same behavior, but in only 8 lines of code instead of 30:
But is it as intuitive?
true
until it’sfalse
. Example for 2 players:Well, it’s shorter anyway.
One final touch: I want to always show the first viewport, even when there are no players:
Related Posts
Godot Engine 4 reaches beta
Just a couple of days ago, Godot 4.0 alpha 17 was announced. Today, Godot Engine 4.0 beta 1 was released. Be sure to check out the announcement. There are lots of improvements across the board; rendering, lighting, physics and navigation, animation, and scripting.
Is Godot is the Linux of Game Engines?
Godot Engine is an open-source game engine. With the 4.0 release on the horizon, it’ll gain quite a bit of attention. And it’s an engine worth keeping an eye on. Internet Gaming. Serious business. Game development is serious business. The global gaming market size was 203 billion USD in 2020 (per fortunebusinessinsights). It is predicted …
Building UIs in Godot 4
Here’s a collection of tutorials that are helpful if you’re new to using Control and Container nodes to create UIs in Godot 4. The Game Dev Artisan video covers creating a simple UI with a reload indicator for a simple 2D tank game: Clear Code’s 11+ hour Ultimate Introduction to Godot 4 has a chapter …
Making videos for the web with Godot 4’s Movie Writer
Normally I use OBS for screen recording, but there are cases where it makes sense to use Godot’s built-in movie writer that was recently announced. For example, if you have a slow PC or really demanding game, OBS will skip frames. It makes sense since OBS is just recording what’s on the screen in real …