1. Research
1.1. Beneficial Weeds http://en.wikipedia.org/wiki/Beneficial_weed
1.1.1. Fertilize
1.1.1.1. Clover and legumes fixes nitrogen http://www.youtube.com/watch?v=UiU-J2f5ED4
1.1.1.1.1. Nitrogen fixing is caused by bacteria that like the clover
1.1.1.1.2. Mix with grass for animal grazing more protein in clover
1.1.2. Improve soil
1.1.2.1. Others use deep tap roots to bring up nutrients and moisture from beyond the range of normal plants, so that the soil improves in quality over generations of that plant's presence.
1.1.2.2. Weeds with strong, widespread roots also introduce organic matter to the earth in the form of those roots, turning hard, dense clay dirt into richer, more fertile soil. In fact, some common plants like tomatoes and corn will "piggyback" on nearby weeds, allowing their relatively weak root systems to go deeper than they could have alone.
1.1.3. Pest Control
1.1.3.1. Many weeds protect nearby plants from insect pests.
1.1.3.2. One way they can do this is to repel insects and other pests through their smell[3], as do alliums and wormwood.
1.1.3.3. Another is to entirely mask a companion's scent, or the pheromones of pest insects, as with ground ivy and wild oregano.
1.1.3.4. Some also are unpleasant to small animals, because of their spines or other features, keeping them away from an area to be protected.
1.1.4. Human Useful
1.1.4.1. Some beneficial weeds, such as lamb's quarters and purslane, are edible. This list of edible flowers includes many wildflowers that are considered weeds when not planted intentionally. Dandelion is an excellent example of an edible weed (see dandelion wine, dandelion coffee).
1.1.4.2. A number of weeds have been proposed as natural alternate sources for latex (rubber), including goldenrod, from which the tires were made on the car famously given by Henry Ford, to Thomas Edison. Cocklebur and stinging nettle have been used for natural dyes. Studies have shown that milkweed is actually a more effective insulator than goose down.
1.1.4.3. Some plants seem to subtly change the flavor of other plants around them, in a way humans find desirable, for example stinging nettle, besides being edible if properly cooked, seems to increase essential oil production in nearby herbs.[4]
1.1.5. List of beneficial weeds http://en.wikipedia.org/wiki/List_of_beneficial_weeds
1.1.5.1. Clover is a legume. Like other beans, it hosts bacteria that fix nitrogen in the soil. Its vining nature covers the ground, sheltering more moisture than it consumes, providing a humid, cooler microclimate for surrounding plants as a "green mulch". It also is preferred by rodents over many garden crops, cutting down on the amount of desired vegetables that get eaten.
1.1.5.2. Dandelions possess a deep, strong tap root that breaks up hard soil, benefiting weaker-rooted plants nearby, and draw up nutrients from deeper than shallower-rooted nearby plants can access. They will also excrete minerals and nitrogen through their roots.[5]
1.1.5.3. Crow garlic, the wild chives found in sunny parts of a North American yard, has all of the companion plant benefits of other alliums, including repelling japanese beetles, aphids, and rodents, and being believed to benefit the flavor of solanums like tomatoes and peppers. It can be used as a substitute for some alliums in cooking, if its slightly more bitter flavor is masked by sweetness or lipids.
1.1.5.4. Bishop's lace (Queen Anne's Lace) works as a nurse plant for nearby crops like lettuce, shading them from overly intense sunlight and keeping more humidity in the air. It attracts predatory wasps and flies that eat vegetable pests. It has a scientifically tested[6] beneficial effect on nearby tomato plants, and when it is young it has an edible root, both of these are true because the domesticated carrot is simply a cultivar of this "weed".
1.2. Natural Farming Cocepts
1.2.1. PolyCulture http://en.wikipedia.org/wiki/Polyculture
1.2.1.1. Crop Rotation is the practice of growing a series of dissimilar types of crops in the same area in sequential seasons. http://en.wikipedia.org/wiki/Crop_rotation
1.2.1.1.1. Replenishment of nitrogen through the use of green manure in sequence with cereals and other crops. Crop rotation also and can also
1.2.1.1.2. mitigates the build-up of pathogens and pests that often occurs when one species is continuously cropped,
1.2.1.1.3. improve soil structure and fertility by alternating deep-rooted and shallow-rooted plants.
1.2.1.2. multiple cropping is the practice of growing two or more crops in the same space during a single growing season
1.2.1.2.1. .It can take the form of double-cropping, in which a second crop is planted after the first has been harvested,
1.2.1.2.2. or relay cropping, in which the second crop is started amidst the first crop before it has been harvested.
1.2.1.3. Intercropping is the practice of growing two or more crops in proximity. The most common goal of intercropping is to produce a greater yield on a given piece of land by making use of resources that would otherwise not be utilized by a single crop. Careful planning is required, taking into account the soil, climate, crops, and varieties. It is particularly important not to have crops competing with each other for physical space, nutrients, water, or sunlight.
1.2.1.4. Companion planting is the planting of different crops in proximity (in gardening and agriculture), on the theory that they assist each other in nutrient uptake, pest control, pollination, and other factors necessary to increasing crop productivity. Companion planting is a form of polyculture. http://www.ghorganics.com/page2.html http://en.wikipedia.org/wiki/List_of_companion_plants http://counties.cce.cornell.edu/chemung/agriculture/publications/companion-planting.pdf
1.2.1.5. Forest gardening
1.3. Soil Info
1.3.1. https://www.gov.uk/managing-soil-types
1.3.2. http://www.pbs.org/journeytoplanetearth/education/agriculture.html
1.3.3. http://smallfarms.oregonstate.edu/improving-soil-quality-crops
1.3.3.1. http://extension.oregonstate.edu/catalog/pdf/ec/ec1561.pdf
1.4. Sand/ Silt / Clay / Loam
1.4.1. SANDY SOIL: Sandy (or light) soils are soils in which silt and clay make up less than 20 percent of the material by weight. These soils drain well, but have little capacity to hold moisture and plant food. Sandy soils have comparatively large particles that permit good aeration, quick passage of water, and quick warming. CLAYEY SOIL: A clayey soil must contain at least 30 percent clay and is known as a heavy soil. Heavy soils have relatively poor drainage and aeration capabilities. Because of this, heavy soils tend to hold more moisture than is good for plants. However, this type of soil also holds fertilizer and plant food well, which can be beneficial to plant growth. LOAMY SOIL: This is the most desirable soil for agricultural use. Loam is a mixture of approximately equal parts of sand, silt, and clay. If loamy soil has more sand than silt or clay, it is known as a sandy loam; more clay, it is known as a clayey loam; more silt, a silty loam.
2. Gravity Garden is a science fiction themed farming simulation. You're in charge of your own private island, floating through an alien space full of bizarre plants and colorful critters. This is an open-world simulation of plants that live and grow according to the conditions in their environment. Plant your garden in any soil - no preset plots or rigid, square fields. It's a sandbox experience where you are free to do as you please. Work towards a series of increasingly difficult achievements or simply grow a beautiful garden and admire the view - it's up to you.
3. Gameplay Goals
3.1. Main Game Loop
3.1.1. plant seeds
3.1.2. care for plants
3.1.3. harvest fruits
3.1.4. convert fruits to seeds or in-game 'currencies' like food, energy, fertilizer
3.2. Challenging the Player
3.2.1. Produce enough food and energy to survive and thrive
3.2.2. Defend your plants from pests
3.2.3. Discover how to maximize health and productivity of each plant
4. Content Goals
4.1. At least 20 different plant species
4.2. 6 or more pests
4.3. several tools and machines to purchase that make caring for plants easier and more efficient
4.4. wide variety of floating islands for exploration and planting.
4.5. lots of Alien Artifacts to find and collect
4.6. variety of decorations and upgrades for the player's home base
5. Design Goals
5.1. Open-world sandbox with optional achievements/goals
5.2. Player is free to plant things wherever there is soil. No grids or rigid plots to fill.
5.3. Each plant is a distinct entity that grows according to the condition of the soil and surrounding environment.
5.4. Hundreds of active, growing plants
5.5. Many VR locomotion options.
5.5.1. Teleport
5.5.2. Traditional First Person controls
5.5.3. Zero-gravity flight
5.5.4. Comfort options like snap-turning, tunnel vision, instant acceleration, etc
5.6. Play while seated, standing, or roomscale
5.7. Simple interface that works with both the HTC Vive and Rift+Touch
5.8. Colorful, consistent art style
5.9. 'Juicy' interactions
5.10. Rewarding exploration and fun surprises
5.10.1. Find new plants and pests
5.10.2. collect alien artifacts
5.10.3. find new areas for growing plants
6. Design Challenges
6.1. Save/Load System
6.1.1. Saving and restoring the full state of every active plant and object will be a complicated coding challenge.
6.2. Keeping performance at 90 fps while simulating large numbers of plants.
6.2.1. I've had successful tests with over 2000 copies of a single, simple plant, but variety and more complicated plants will put more strain on the systems that I have in place