My first question concerns the "pressure_to_speed_ratio" attribute and how flow speed is calculated. I know that pressure is calculated by the difference in "fullness" (current fluid/max capacity) between two pipes, but how does the game engine decide how much fluid to transfer? Does a value of 0.4 mean that 40% of the difference in "fullness" is transferred per tick? Or is it something different entirely? Ideally, I would like to be able to calculate what exactly happens on each tick and be able to account for larger/smaller pipes producing different levels of pressure, as well as for modded liquids that have a different pressure_to_speed_ratio.
In addition, while testing I found the baffling situation that eventually prompted me to ask for help. Pictured below is a 2 offshore pump to 20 steam engine setup with the debug option "show_fluid_box_info" on.
http://puu.sh/jTq8D/b7f99a2ba4.jpg
I have two questions. First, what is the blue bar representing? I assume the green bar is the fluid contained in the pipes/pumps/steam engines, but I can't figure out the blue one. My best guess is something to do with the pressure in the pipe, but honestly I have no idea.
Second, why does the random pipe in the middle contain more fluid? The line of pipes steadily decreases in "fullness", which is expected based on how fluids flow, yet that one pipe contains 6 units of water while the one to the left contains 4.5 and the one to the right contains 3.5. The phenomenon repeats itself in the steam engines as well, though I can't find any sort of pattern to the higher fluid levels other than all of them having a blue bar where the others don't have one.
Hopefully someone out there knows a lot more than I do about fluids, because I have to admit I'm pretty stumped. Any help would be much appreciated.
