Calendon

A 2D single-threaded main loop C99 game engine for prototyping and learning.

Under active development, not suitable for production use.

Goal

• Speed the iteration time when creating 2D game demos and visual simulations.

Method

• Dynamically load games/demos/prototypes with minimal interfaces and boilerplate, so programmers can focus on the ideas they want to experiment with and iterate quickly before adding to production systems.

Guiding Design Principle (ASAP/ASAP)

• "As simple as possible": Doing things with the engine should be straightforward and explicit, but it might be more verbose than languages with more features than C. That's ok.
• "As soon as possible": Use the ability to create prototypes to streamline the development process by trying ideas in fast-to-compile sandboxes.

Limitations of Scope

• No true 3D support. Many issues get much more complicated and harder to visualize and reason about in three dimensions.
• Core functionality shall only be written in C. C provides mostly predictable symbol generation and more centralized control flow making it simpler to reason about program behavior while learning. It also simplifies interfacing with other languages.

Overview

The only code you write for Calendon is a game module which gets loaded by a driver program at runtime. Your game accesses Calendon functionality using the same Calendon library that the driver does.

How to Build

Required Tools

Everywhere:

• cmake v3.10 -- https://cmake.org/download/
  • Generates build configurations
• git -- https://git-scm.com/downloads
  • For source control
• python 3.7 -- https://www.python.org/downloads/
  • For the project's build/test front-end, crank.

Linux:

• SDL 2.0 libraries
• ccache (optional, improves build speeds)

Mac:

• I don't have a Mac to test on so I don't know if Calendon will even build on this platform. If you're willing to help with Mac support, let me know!

Building and running the demos

crank is a python wrapper for cmake and other tools, so people on different platforms or with different IDEs, can do builds and run tests in the same way. It also requires programs to register themselves so you know what tools your build is using. The only registered tool required to do a normal build is cmake.

Your installation paths might be slightly different than those given here.

Windows, using powershell:

py/crank.py register cmake "C:/Program Files/CMake/bin/cmake.exe" 

Linux:

py/crank.py register cmake /usr/bin/cmake

Now you can generate your build files and build

py/crank.py gen
py/crank.py build

and run demos:

py/crank.py run planets
py/crank.py run koch-curve
py/crank.py run graphics-sample

Testing

py/crank.py check

Help

 py/crank.py --help