Umbra Octane Mech

Octane Mech is a 3D, OpenGL based Mech game

umbra mech - opengl based game

glAnts is an example OpenGL C++ project that simulates a mech-style game featuring 3D rendering and basic real-time networking. Originally written in C, it's a retro-style graphical demo showcasing object-based rendering, camera movement, particle effects, and rudimentary multiplayer capabilities. It's useful as a learning project for OpenGL, game architecture, and client-server networking concepts in C++.

Updates 2025

See the most recent updates under the gameupdates directory

Older code can be found under "legacy"

History

The game started around 1999 many years ago. The goal was to run on Linux and Windows. When OpenGL was coming out, to support graphics card including 3dfx cards.

Remaster and Relearn Journey

As part of the remaster and relearn, I converted some of the code to compile and had to break the code down into small modules.

See the updates as some basic OpenGL in C/C++ examples

Navigate to the directory: https://github.com/berlinbrown/OctaneMechOpenGLGame/tree/master/retutorials

...

Also see: http://code.google.com/p/octanemech/

Developer guide 🔧

Quick start (mac)

• cd gameupdates/mac/umbramech
• make build (wrapper for cmake -S . -B build && cmake --build build)
• make run or ./build/bin/umbramech
• To build a debug build: cmake -S . -B build -DCMAKE_BUILD_TYPE=Debug && cmake --build build
• Notes: CMake links macOS frameworks (-framework OpenGL -framework GLUT -framework Cocoa -framework IOKit -framework CoreVideo). The project disables deprecated OpenGL warnings with -Wno-deprecated-declarations.

Big-picture architecture 🧭

• Primary active code: gameupdates/mac/umbramech/ — include/ (headers), src/ (implementation), resources/ (config and assets).
  • Entry: src/umbramain.cpp (main loop, input, HUD, GL setup)
  • Globals & config: include/globals.hpp + src/globals.cpp (see Load_ConfigFile())
  • Rendering helpers: src/gldrawlib.cpp, src/objects.cpp, src/particles.cpp
  • Game entities: src/bot.cpp, src/fireants.cpp, src/DriverBots.cpp
• Legacy code and platform variants live under legacy/ and octanemech/ (consult for older implementations and networking details).

Project-specific conventions & patterns 📐

• Heavy use of a single global state: AntGlobals *ant_globals and many macros mapping fields (e.g., #define BOT_SPEED ant_globals->bot_speed). Search ant_globals to find where state is used/modified.
• C-style structs and global macros dominate; prefer minimally-invasive edits (follow existing style unless doing a focused refactor).
• Config-driven: resources/config.ini is parsed by Load_ConfigFile() and maps many runtime settings to ant_globals fields (look for ID_* constants in include/globals.hpp).
• UI/menu state and input mapping are centralized in umbramain.cpp with macros like MENU_RUN_MODE and functions such as TogglePaused() and GameTick().
• Rendering uses the OpenGL fixed-function pipeline (immediate mode, glBegin/glEnd, gluPerspective) — expect deprecated APIs on modern macOS; porting should be incremental.

Debugging & development tips 🧪

• There are no automated test suites; prefer manual builds and visual verification for rendering changes.
• Use Super_Printf() for in-game debug output and the Super_* helpers for text/UI debug features.
• When working cross-platform, inspect platform-specific blocks (X11/GLX vs macOS GLUT) before editing.

Network & integration 🕸️

• Network/server/client code is available in legacy paths (e.g., legacy/.../src/network/). Consult these files for multiplayer behaviour and protocols.

Contributing & style ✅

• A .clang-format is present at the repo root (Google-based with project tweaks) — run clang-format -i on changed C/C++ files.
• I applied code formatting across C/C++ sources on branch style/clang-format (recommended to review changes in a PR).

Notes: Files include BSD-style license headers (Berlin Brown). Preserve license headers when editing files.

If you'd like, I can add a short "how to test" checklist or a developer CONTRIBUTING.md — which would you prefer?