Let’s Make a Skill Tree
Hello coders! Captain Coder here with another learning series. On the Captain Coder’s Academy discord, it was proposed that I implement a Skill Tree live on stream. I felt this fit into the current theme of prepping for the 2023 Dungeon Crawler Game Jam
This site serves as a blog that will (hopefully) chronicle the streams for anyone who missed them live and recap what we accomplished each day. I hope someone finds this blog useful!
- Archived Streams Playlist: Playlist
- Catch the Captain Live on Twitch: Twitch
- Source Code: Repository
Project Overview
The goal of this project is to create a functional skill tree system that can be dropped into an existing project, restyled, and reused.
Day 1 - Design Document and Project Scope
Today, we defined our learning goals, specified the scope of the project, setup a unity project, class class library project, xUnit test project, and defined a few interfaces: ISkilledCharacter, ISkillNode, and ISkillTree.
Day 2: Skill Tree Builder and Unit Testing
Today, we implemented a SkillTreeBuilder class that allows for construction of an ISkillTree. While implementing this, we discovered a few flaws in our interfaces which we corrected. Additionally, we wrote unit tests to validate that the SkillTreeBuilder we implemented was correct.
Day 3: Manually Building a UI
Today, we manually built a visual representation of a Skill Tree using Unity’s UI Toolkit. Additionally, we explored the Vector Graphics API to automatically connect nodes in the Skill Tree together.
Day 4: UI Generation: Version 0
Today, we defined ScriptableObjects which can be used to specify a skill tree. Then, we attempted to write a tool to automagically generate a UI based on a skill tree. Unfortunately, we discovered that the desired behavior may not be possible using a subclass of the VisualElement class. Off stream, the Captain explored generating UXML which does have the intended behavior.
Day 5: UXML Serialization
Today, we implemented UXML Generators for our SkillTree and SkillNodes. Additionally, we updated the Skill Nodes to be intractable. Lastly, for convenience, we updated the UXML generators to be aware of position changes by deserializing the existing UXML prior to regeneration.