I guess this is the problem I mention in my code here: https://github.com/s-macke/Interplanetary-Postal-Service/blob/master/gameWASM/fluid.c#L510 https://github

I guess this is the problem I mention in my code here: https://github.com/s-macke/Interplanetary-Postal-Service/blob/master/gameWASM/fluid.c#L510 https://github.com/s-macke/Interplanetary-Postal-Service/blo... For the sake of optics I use wrong boundary conditions for the colored part of the fluid (transport equation). The right solution would be to copy the density[]-grids and apply the wrong boundary conditions on them and then draw the image with it.