Ecosystem simulation

This project aims to be a simulation of a basic ecosystem. This is inspired from Daniel Schiffman's simulation which can be found here.

Current version: 1.1.0

Building

This project uses a CMakeLists.txt file to build the project. The parameters for the cmake command are listed below.

Parameters

Option name	Description
OUTPUT_DIRECTORY	The output directory where the binary is gonna be located.
SFML_ROOT	The path to the SFML root location (in case Cmake can't find it properly with FindSFML.cmake).

Windows

Prerequisites for Windows

• Visual Studio 15 / 17
• CMake > 2.5
• C++14

Instructions for Windows

Clone the repository, open a command prompt in it and type:

Example 1 (32 bits environnement):

mkdir build
cd build
cmake ..
cmake --build .

Example 2 (64 bits environnement):

mkdir build
cd build
cmake -G "Visual Studio 15 Win64" ..
cmake --build .

Example 3 (using CMake options):

mkdir build
cd build
cmake -DOUTPUT_DIRECTORY=..\bin -DSFML_ROOT=C:\path\to\your\SFML\location -G "Visual Studio 15 Win64" ..
cmake --build .

Linux

Prerequisites for Linux

• g++
• CMake > 2.5
• C++ 14

Instructions for Linux

Clone the repository, open a terminal in it, and type:

Example 1 (without CMake options):

mkdir build
cd build
cmake ..
make

Example 2 (with CMake options):

mkdir build
cd build
cmake -DOUTPUT_DIRECTORY=../bin -DSFML_ROOT=/path/to/your/SFML/location ..
make

Running

Running on Windows

Make sure the different .dll files are in the folder where the executable is. Those .dll files are needed:

• freetype.dll
• jpeg62.dll
• libbz2.dll
• libpng16.dll
• sfml-graphics-2.dll
• sfml-system-2.dll
• sfml-window-2.dll
• zlib1.dll

Then, you should be able to run the executable Ecosystem_simulation.exe.

Running on Linux

You should be able to run the simulation by opening a terminal in the output directory and type:

./Ecosystem_simulation

Keybindings

• Enter: Starts the simulation

• Escape: Ends the simulation

• Space: Pauses/Resumes the simulation

• Left arrow: Slows down the simulation by 2

• Right arrow: Speeds up the simulation by 2

Functionning

• There are 30 cells, spawning randomly on the window at the beginning of the simulation.

• A cell has a random radius value, from 5 pixels to 50. The biggest the cell is, the slowest it is (from 10 pixels/second to 50). At the beginning of the simulation, each cell has 100 HP. Each second, the cell loses 3 HP. When a cell has no longer HP, it disappears: the cell is dead. A full HP cell is green, while a almost-dead cell is red.

• Each 0.7 seconds, a food appears on the window. A food is represented by a blue octagon. When a cell comes into contact with a food, the cell eats it and regain 20 HP.

Here's a short video how this simulation looks like:

This simulation uses SimplexNoise to simulate a natural movement for the cells and SFML to render the graphics.

Customizing

You can customize pretty much all the settings of the simulation, such as:

• The maximum HP of the cells

• The number of HP lost per second

• The minimum / maximum radius of the cells / food

• Cells / Food color

• The minimal / maximal speed of the cells

• The number of seconds between the spawn of two two piles of food

• The number of HP the cells regain by eating food

• The color / size / font of the text

... and more.

You just need to change the constants values in the file src/constants.hpp.

Possible improvments

• A more random natural movement for the cell. Currently, the movement is a bit predictable (the cells are more likely to move at the center of the window). Brownian movement?

• Gather the info about the results of the simulation and write it down in a file. So, we could make statistics about the simulation.

• Speeding up / down the simulation. (Version 1.1.0)

• Save the animation in a .mp4 file.

• Timer for the duration of the simulation. (Version 1.1.0)

• Generations system (with genetic inheritance).

Contributing

If you want to improve this project, feel free to create a pull request. Make sure your code respects the settings of the .clang-format file.