psyinf / 2dplayground

2dPlayGround

A small playground 2D game engine to create a mini-game that is based on SDL2, ImGu, EnTT and an minimal custom made OpenAL sound-engine.
In principal I tried to stick modern C++ wherever it made sense, mainly to keep myself up2date with new possibilities to make the code more readable, efficient and safer.\

Prerequisites

The project uses CMake Package Manager
As the project uses some advanced C++ features (aiming to use C++23) a recent compiler is needed. See next section for details

• CMake > 3.22
• GCC > 14.1 or Clang 17.0.3 or the MSVC 2022 compiler

It is tested on Windows using VS2022 and inside an Ubuntu environment (24.04) but might also work on other distributions.

Build

The project uses CMake and comes with presets, so building is a trivial as:

cmake --preset=unixlike-gcc-release
cmake --build --preset=unixlike-gcc-release

All available presets for your target platform:

cmake --list-presets

Visual Studio and VS Code will also work either directly for Windows or using WSL.

Project structure

The project currently consists of 3 major parts/folders

• libs
  • pgFoundation
  • pgEngine
  • pgGame
• apps
  • sandbox
  • galaxy
  • asteroids
  • ... some other
• tools
• tests

tests

Catch2 based unittest. By far not complete.

tools

All tools for creating resources etc. Currently there is only a collisionShape generator that produces convex hulls from sprites.

libs

pgFoundation

Comprises of some classes and facilties that are not directly specific to this. Is a candidate to be moved outside the project

├── caching      
├── imgui
├── paths
├── serialization
└── strings

pgEngine

Some attempt to build a minimal game engine which in principal is based on SDL2 (in detail it is using sdlpp). It provides core an core architecture by abstracting an application, event loop, math and rendering primitives.

The math library contains a minimal linear algebra library (as i found GMTL/my GMTL fork clumsy and outdated and eigen to much for what I wanted initially. I've also considered GLM ). With it I added some minimal space partitioning (a KDTree) and some minimal collision code.

pgGame

Extends the pgEngine using ECS (EnTT) to provide basic entities, a system abstraction and basic resource and scene management.

apps

Asteroids

This serves as a simple tech demo and concept playground. It is based on pgGame and therefore is a based on an EnTT. There is still a lot to learn and to experiment with.

Galaxy

A small portion of a game idea I developed some years ago. It basically revolves around vonNeumann probes and is currently developed into a working game.

Sandbox et al.

All other folders are for testing, messing around and minimal tech demos.

Running

If you want to try, you can use the install targets created by the cmake-configure step. They will install all resources, libraries.

Troubleshooting

2dplayground's Issues

proper drone movement properties

The movement needs to honor the maximum speed and acceleration
This also requires some definition of units. E.g. a distance should be in lightyears and time units defined.
With this we can define the maximum speed as percent of 'c'

Crash on quit during LoadingScreen

If window is closed during loading of resources, threads access destructed facilities

frameTicks time representation

convert to days/months/years representation

e.g. in senttbox we hade years/months/days/fractional_days

Starsystem handling

Starsystems need:

• resource abundancy
  ** time to build drones (exponentially decreasing? due to harder to extract resources)
  ** number of drones that can be built
• hazard situation
  ** how much can production be hampered by solar storms etc.
  later:
  defense platforms/drones to avoid being captured by enemy

frame time based drone movement

Dronesystem needs to use the framestamp

Minimal galaxy configuration via json

Conceptualize balancing

Factions follow different strategies

• trade-off speed over reliability (higher speed equals higher prob and effect of collision incidents
• max distance vs speed
• idea: if a drone cannot find a target within range, trade range for speed

combat strategies:

• sub-drones for attacks
• directed weapons
• attack production vs drones
• suicide attacks vs facilities

production strategies:

• facility vs resource vs drones

later:

• aggressiveness vs avoidance (when searching for new systems, drones can choose free over hostile planned systems)

idea:

• attack, defense, speed tradeoffs

tradeoffs:

• speed/acceleration vs max distance
• reproduction rate vs failure rate

State machine for Drones

move math operators to namespace

all named operators should go the the pg namespace

Simple DearIMGui Overlay

Quadtree circle query

The Quadtree implementation needs a circle query
[ ] add circle primitive
[ ] add interface