LitSimulate is a simulator which simulates what LitSpin will display. We developed the first versions with PyOpenGL and PyGame.

## Image Format

Each 3D image is represented by a classical image. If we note r the radial resolution (total number of columns), h the number of LEDs by column and n the number of steps by rotation, our image dimensions are rh x n. In our case r=20, h=32 and n=128. So we have 640×128. One line represents the n points one led will display. And each block of h lines represents the 360° image of a column from the outermost to the innermost (from 1 to r). Just below an example with r = 8.

## Examples of simulation

We made some simulations with r=10, h=10 and n=100

## Limitations

For now, we simulate an 8-bits-by-colour display and not a 9-bits-by-colour one. This is just because it is easier to create an 8-bits image on the internet rather than 8 bits. However, it will be very simple to change LitSimulate into a 9-bit simulator.

The main issue is a problem of memory. Indeed, the RAM is constantly filling up until the PC is completely blocked. So we can only use this first version of the simulator for a few seconds. Moreover, we can’t simulate with our real values of r, h and n because it takes too much memory to display the results. To deal with this issue there will be several steps:

- We will try to fix it by keeping Pygame et PyOpenGL
- If we can’t, we will try without PyGame and only use PyOpenGL (because PyGame is used to initialize OpenGL display). Maybe we would directly go to step 3
- If it is still too slow, we will make the simulator in C++
- If it is still too slow or too complicated, we will try the Point Cloud Library for C++