Volume2D shader

Recent Updates

2021.8.26 Major revision in Volume, delete much redundant code. Make the logic clearer and simpler, more efficient.
Some bugs are fixed, and the new updates are tested in 4 new maps seen as follows.
- Able to handle the boundaries which cover more than 360 degs.
- Able to run in a "Room like" (relatively closed) maps.
- Better occlusion judgement strategies, less code than before.
- Four new standard maps are added in the folder maps
- Mouse control in OpenCV 4, much easier to control your source of light.
- Notice that if you are looking for a 2D LiDAR simulator, I have built a simple simulator upon this repository, see [Enigmatisms/ParticleFilter], which is awesome.

I. Introduction

This C++ repo is for a 2D real-time “volume light” generator, designed for irregular obstacles. I have implemented the algorithm for regular obstacles (squares) in repo: [Enigmatisms/Algorithm-Plus], therefore, this one is regarded as A 'Volume 2D Shader Pro'.

The main body of this algo is god-damn fast, 23 obstacles in 1200 * 900 (pixels) canvas, it runs at 6000-12000 fps (without visualization.). Most consumption of time is due to visualization (Function visualizeVisualSpace).

II. Have a Try

2.1 Dependencies

The dependent libraries are (Ubuntu 18.04)：

Name & Version	Roles
OpenCV 3.3.1	Visualization, video saving, user interaction
Eigen 3	Matrix computation and data representation.
CMake + C++17	Compilation tool, yet features of C++ 17 is not used.

2.2 Compilation

cd volume/
mkdir build/
cd build/
cmake .. && make -j

After executing the command lines above, two executable files are generated: ./main (main body of this "shader")，./editor (map editor)

2.3 Map Editor

I provide you with a map editor, with which you can design your own maps for trying out. However, there are something that need to be make clear:

The outer boundaries are given (30-pixel-thin), therefore don't draw anything in the border.
Objects (Obstacles) are directional (all the points of each any one of the obstacles should be drawn in a anti-clockwise way)
execute this：

cd volume/
mkdir maps/				# skip if folder 'maps/' is already in the root folder
cd build/
./editor <map name>

Enters the name of your own design. Map files are stored in maps/, if the file with the same name already exists, it will be replaced.

2.4 Volume Shader

cd volume/build/
./main <map_name> <speed>

Run as the instructions above, `./main requires some parameters:

<map_name>: map file name, no 'path-to-file' and post-fix needed.
<speed>: The speed of the light ball you are controlling.

Execution procedures:
Use your mouse to set the initial position of the light ball.
w, a, s, d will control the direction of your moving, ESC for exiting.

III. Demos

To have more information of this repo and algorithm, see the personal blogs of mine [Event Horizon].