This is not going to be a clean read guys.
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NOW POSSIBLE IF COMBINED WITH THIS SUGGESTION So the basic idea is about waste and so forth. I have drawn all of the ideas in this mockup that consists of several 9x9 images:
The basic idea is that all animals would need to produce waste. For instance the top row shows a dwarven bathroom.
As you can seem the first slide in the first row shows a floor with enclosed rooms that contain grates. also, two of the rooms are occupied by dwarves. I made the rooms contain grates because I didn't thing there should be a toilet item...yet at least. The next image shows the level bellow the dwarves. When a dwarf would go to the bathroom, he would drop an item known as...Lets just call it XXXX. If more than one XXXX is ever present in a tile, then the XXXX is gone and 1 unit of waste appears. Yes, the waste is going to have to be a liquid. The third and fourth image shows how the waste would collect in a large container that would fill up over time and can be emptied via floodgates.
The waste would be unique with that fact that if 3/4/5/6/7 units of waste are present in a tile, and have not moved for a while, then they would turn into a tile of waste compost. The first image in the second row shows how waste can be filled up from a single XXXX to a full 7 units of liquid waste. Also, the Solid waste would have different densities ranging from 1-5. a dwarf can use any ammount of waste as a ramp.
The third and fourth images in the second row show how a dwarf, if unable to find a bathroom, will try to do his business in a place where nobody can see.
In case you didn't get it, the green dot is a XXXX.
Also, as the second image in the second row shows, liquid waste will turn into miasma and XXXX's once it touches water. therefor waste can be disposed of.
Solid waste compost can be used as fertilizer for crops, as shown in the first image in the 3'd row.
If liquid waste is outside(in the sun) then a unit of liquid waste will only move around if any nearby tile has an ammount of waste that is atleast two units less. Therefor, liquid waste in the surface will not travel far if dumped and will, after turning into compost, form neat piles if the stuff, as shown in the second image in the third row.
Also, remember that any animal will/can produce waste. As the the third image in the third row shows, a pack of horses in a pasture are leaving a bunch of XXXX's behind them.
The fourth image in the third row shows how a stable dwarf(a new profession) is using a wheel barrel to pile waste compost in the appropriate stockpile.
The first image in the fourth row shows how there can be many types of composts. The first is a dark green type that is made from XXXX's(Any XXXX that is left out can be placed in the stockpile to create not liquid waste but this compost), rotten food and withered plants. The second is solid waste compost witch can be made from liquid waste and added chaff(this would have to be ingame though) to create it. The chaff will simply make it bigger since there is no other reason for it. The third could be cmade from anything dead and the fourth can be made from any milk, alcohol, ichor, blood and vomit. The idea is that there could be some plants that require compost to grow.
The second image in the fourth row just shows how wheat should produce chaff that can be turned into bales. I dont know why I added that there.
The third image shows how, if a dwarf falls into compost, that is not full(5) then he will get stuck and require somebody to help him out and not take any damage from the fall. I added that because this once happened to me(I live in a farm)
And the last image shows...*DRUMROLL*...The liquid waste powered goblin encasement room.
Thoughts contributions appraisal and sritisism welcome! Trolls are not! For all trols, theres the building destroyer trap -> I&&&0