Development Documentation of River

River is a game designed to simulate the system of rivers and relationship between early human civilizations and rivers. In the game, the player act as the source of a river and is able to press space bar to add more water into the river. The goal of the player is to control the river and make it as stable as possible, otherwise humans living near the river will lose their life by drought or flood. Or player can also creates a massive flood and murder everyone. 

This game is inspired by the river system, human population system, and the relationship between them. Elements in a river system are river, source, destination, raining, evaporation, and human activities. Water comes from the source and flow to the destination. Other elements like raining, evaporation, and human activities can affect the amount of water in the river. When the outflow(evaporation and human activities) is larger than the inflow(source and raining), the river is likely to dry up. If the inflow is higher, the river is likely to flood. For human population system, the inflow and outflow are fertility and mortality. There is a reinforcing loop in this system that large population will have higher fertility and enlarge the population. Human population in early ancient civilization requires a stable environment to grow. Natural disasters like flood or drought are likely to cause a decline in population. The river system is not always stable, so human population is depending on the situation of the river.

To reproduce it in the game, I want to create an unstable river and a fragile human population. In the game there is a value to represent the amount of water in the river. The value slowly increases after player press space bar, and constantly decreases due to evaporate. To exaggerate and visualize the effect of evaporation, there are max of three suns in the game and the number of suns will randomly change by a constant pace. When there are more suns in the sky, the impact of evaporation is larger and the river become harder to control. Humans in the game automatically have houses and crops, representing shelter and food resources for ancient civilization. If the water level is too low, crops will die and humans will eventually starve to death. If the water level is too high it will become a flood and sweep crops and even humans. To simulated fertility and mortality, human population is increase based on a reinforcing loop. Every human also have a constant lifetime and will old to die. Crops in the game also consume water, so if when population goes higher, the consumption also goes larger and make the game become harder.

The most interesting part I want to play with in this system is the relationship between the human and river. Ancient civilizations are depending on rivers to survive, but some rivers(like in Mesopotamia) are really unstable. These civilizations are suffered from the stability of rivers. Unlike today we can sort of control the nature, those ancient people have no control on nature have to beg the river to let them survive. Therefore, the game is made in the view of river and player(the most unstable element in a game) is able to control the river. The game is also played with the idea that nature doesn’t care. The player usually won’t really care about the life or death of pixel humans in the game. Even they do care, they still have to fight(or cooperate) with the sun to stabilize the river.

If I have more time, I would like to add raining system into this game, because it would add a random inflow to the system and make it harder and need more strategy to control the river. I also like to make the human in this game develop after time and eventually able to make the river more controllable by technologies like flood bank. At the same time the human activities are going to consume more water and cause the river to dry up, or they pollutant the water and kill themselves.