Source Code: https://github.com/Konoca/Co-Op_HUD_plus
Download: https://steamcommunity.com/sharedfiles/filedetails/?id=3229942849
Technologies
- Lua
- The Binding of Isaac: Repentence API
- Repentogon: TBoI:R API Extender
Overview
Co-Op HUD+ is a mod I created for the game The Binding of Isaac: Repentance that completely overhauls the in-game HUD to better display information when playing with friends. With 2 players the default HUD is fine, but anyone who joins after loses important information about their character such as their stats and current items. This was especially bad if anyone was playing the character “Jacob & Esau”, since you are essentially controlling two separate characters with their own items, stats, and health.
My solution was Co-Op HUD+, a mod that completely disables the default HUD and recreates it from scratch to better display all necessary information for all players. I even provided the ability to fully customize the layout of the HUD, giving users full control of how their games looked.
Along with endless possibilities for customization, I also prioritized performance. Because this mod was constantly drawing graphics on the users screen, it would have been very easy to accidentally create a mod that made users games unplayable due to how slow it became. A large amount of time was spent optimizing the code, following all best practices defined in the Lua Documentation. Because of this, users experienced little to no change in their games performance, despite Co-Op HUD+ being a very large mod!
Reception
On launch the mod was an instant hit, gaining nearly 1,000 users in the first day! The mod eventually even reached a peak of over 2,000 active users and has achieved a 96% positive rating by users! In its lifetime, the mod has reached nearly 13,000 visitors on Steam, and nearly 5,000 unique subscribers.
Features
- Renders active items, hearts, pocket items, and trinkets in a readable position for all four players
- Renders picked up collectibles for all players!
- Stats for all four players displayed relative to their character info (P1 and P3 on left, P2 and P4 on right)
- Player color coding (P1 Blue, P2 Red, P3 Green, P4 Yellow)
- Press H to switch between Co-Op HUD+ and the default HUD
- Timer always shown at the top of the screen
- Tainted Isaac Inventory correctly displayed for all players
- Tainted ??? Poop Spells correctly displayed for all players
- Tainted Cain Bag of Crafting correctly displayed for all players
- Entirely customizable!
Compatibility
Because I was overhauling the entire HUD, there was going to be issues with any other mod that needed to add anything new to the HUD. While this was not common for the vast majority of mods, there were a few popular ones that did cause issues. Specifically, major mods such as Fiend Folio and Epiphany added custom hearts and UI elements.
The custom hearts that mods like Fiend Folio added were all added using a custom library called “Custom heart API” (CHAPI). So, in order to add compatibility with any mod that adds hearts, I had to add support for CHAPI. This was not simple since nearly all mods that use it do not even mention they are using CHAPI, so it was very difficult to even find what the problem was. However; once it was discovered that CHAPI was the culprit, I was able to detect if CHAPI was present and change how hearts were rendered to follow exactly what CHAPI needed. This provided support for the majority of remaining mods that caused issues!
Mods like Epiphany on the other hand added their own custom UI elements. For mods like this, support needed to be manually added. Because I could not add support for every single mod that does this I manually added support for the biggest one, and provided developers with an easy way of adding support on their own using a simple interface!