Planets

A C++ Simulation of Newton's Law of Gravitation.

Watch some of the simulations here:

Table of Contents

• Building From Source
  • Linux
  • Windows
• The Universe Through Lua
• Configuring the Universe
• Keybindings

Building From Source

Linux:

Step 1: Clone this repository and cd into it

git clone https://github.com/AzeezDa/Planets.git
cd Planets

Step 2: Build with CMake

mkdir build
cd build
cmake .. -DCMAKE_BUILD_TYPE=Release
make

This step will take a bit of time.

Note: You can use -DCMAKE_BUILD_TYPE=Debug (which is the default) instead to add in the debug symbols.

Step 3: Done!

You can now use the Planets executable to run the Lua universe file. For example if you are inside the build/ directory:

./Planets ../Examples/Twins.lua

should display the spinning twin bodies.

Windows

If you are using Visual Studio, it should be able to build the project automatically when this project is opened for the first time in Visual Studio. (Tested with Visual Studio 2022 with the Visual C++ package installed)

If you are using WSL, you can follow the Linux steps above. If no window pops up at step 3 then you should make sure that you have installed XLaunch or similar.

The Universe Through Lua

To make your own universe, make a .lua file and inside it create a table called Universe (case sensitive). You can populate that table with tables that describe the body's mass (as a number), position (as a table), velocity (as a table) or color (as a hexcolor or words). The accepted color words are: red ,green ,blue ,yellow ,magenta ,cyan ,white ,grey and orange

See the Examples/ directory for more guidance.

Configuring the Universe

You can configure the graphical settings of the simulation for each universe you create in the Lua file.

In your universe Lua file create a table called Config that you can populate with:

• windowSize = {1080, 720} - The default size of the created window
• fpsLimit = 60 - The maximum Frames Per Second for the simulation
• AALevel = 4 - The Anti-aliasing level for the simulation

The values given above the are the default and if the key for the configuration is not present in the table then those values will be used instead.

See the Examples/TwinsWithConfig.lua file for more guidance.

Keybindings

• You can zoom in and out with I (for In) and O for out.
• You can zoom in and out with the mouse wheel
• You can move around by dragging the screen while pressing the left mouse button
• You can move around the camera by using WASD (for Up, Left, Down and Right)
• You can hold space to pause the simulation (but still be able to move and zoom around)