Parts

Parts are Roblox parts in Grassy Landscape that spawn throughout the Map. They can be picked up, welded, and cut by players. Parts come in a variety of colors, shapes and sizes. They are one of the core building materials of the game, the other being items.

Spawning

Upon server start, 4,800 parts are spawned around the map. Each part has a random position, size, material, shape and color. For positioning, the map has designated spawn areas for parts and items. An algorithm picks between these areas, giving each one a probability equal to its volume, then calculates a random position and rotation within the area. For shape, each part has a ~60% chance of being a block and a ~40% chance of being a cylinder.

Materials

For material, one is picked according to the probability table below.

Material	Chance	Value
CorrodedMetal	30.6%	0.8
Metal	19.6%	1
SmoothPlastic	19.6%	1
DiamondPlate	13.6%	1.2
Glass	13.6%	1.2
Foil	3.1%	2.5

Below is the code used to calculate that table, which can be run by any injector such as Synapse or Script-Ware. The reason for the (1 / v) ^ 2 formula is that the part spawning script uses that formula when choosing which material to pick. (confirmed by the developer)

local valuebook = require(game.ReplicatedStorage.ValueBook)

local total = 0
for _, v in pairs(valuebook.MaterialValues) do
	total += (1 / v) ^ 2
end

for _, v in pairs(valuebook.Materials) do
	local value = (1 / valuebook.MaterialValues[v])^2
	print(v, tostring((value / total) * 100) .. '%', value)
end

Sizing

For size, the value of the picked material is used as a bias. The bias skews the random distribution such that higher bias values cause lower random numbers to be more common. In practice this means that parts with rarer materials tend to spawn smaller, but all sizes are still possible. Then, the Y and Z values are randomly generated. Each component is calculated as math.random()^bias * 9 + 1, which means a random number from 1 to 10, skewed by the bias. Again, higher biases (such as foil's bias of 2.5) mean that the size will tend towards the 1, while lower biases (such as in the case of corroded metal) tend to skew towards 10.

The maximum value for the X component will be a value N such that Y * Z * N == 125. In order words the maximum volume of the part will be 125 studs squared. The minimum value of the X component is always 0.2. Then a random number is generated between those two values, skewed by the bias once again.

The full function is thusly:

function Part:RandomSize(bias)
	local y = math.random()^bias * 9 + 1
	local z = math.random()^bias * 9 + 1
	local x = math.min(math.random()^bias * (125 / (y * z) - 0.2) + 0.2, 10)
	
	return Vector3.new(x, y, z)
end

Colors

Parts mainly spawn in dull and muted tones, with some greys and whites mixed in. Rather than a list of BrickColors, part colors are generated as Color3 values, so there is an entire spectrum of possible colors. Nonetheless, the spectrum is limited and is only a small fraction of the color space. Here is a graph showing the entire part color spectrum (click on it for a larger version):

On the left is the hue and lightness spectrum, and on the right is the saturation spectrum. The range of saturation values for a color depends on its lightness, which is why there is a separate saturation graph next to the main one. To pick a color from the spectrum, first the game chooses the hue and lightness from the graph on the left, and then it chooses a saturation from the graph on the right. As you can see, brighter colors have a smaller saturation range.

The color generation code is as follows:

local hue = math.random()
local lightness = rand(0.1, 1, 0.75)
local saturation = rand(0.1, 0.5 - (lightness^0.5 * 0.4), 5)

rand(min, max, bias) generates a random number between its two first arguments, biased by the third argument. Notice that lightnesses below 0.1 are impossible to spawn and so are saturations below 0.1, which are both reflected in the graph.

BrickColors found in-game

This table was generated by TerrodactyI using a special script that collects data from 100 million color generations. It is more accurate than any measurement taken in-game, and it took about 7 minutes to generate.

Visual	Name	RGB	Percentage	Rarity
	Quill grey	222.42, 217.38, 224.41	7.223713%	One in 13
	Mid gray	207.46, 196.67, 198.20	7.049205%	One in 14
	Institutional white	248.08, 246.33, 246.36	6.291832%	One in 15
	White	246.56, 245.87, 244.47	4.385896%	One in 22
	Dark grey	104.81, 130.25, 107.48	4.328141%	One in 23
	Black	49.21, 50.07, 60.15	4.203303%	One in 23
	Ghost grey	197.10, 201.13, 210.98	3.632279%	One in 27
	Sage green	187.03, 200.07, 202.54	3.464172%	One in 28
	Dirt brown	67.21, 60.48, 73.94	3.265487%	One in 30
	Oyster	184.43, 181.80, 168.48	3.241747%	One in 30
	Light grey	192.01, 203.65, 193.66	3.165536%	One in 31
	Light stone grey	227.34, 232.61, 228.96	3.108890%	One in 32
	Earth green	60.52, 55.20, 49.04	3.054798%	One in 32
	Dark taupe	59.21, 82.77, 61.96	2.788590%	One in 35
	Cloudy grey	175.59, 166.23, 150.75	2.762956%	One in 36
	Smoky grey	93.81, 99.67, 117.08	2.683132%	One in 37
	Sand violet	127.55, 112.30, 138.65	2.599409%	One in 38
	Sand green	110.27, 128.67, 134.78	2.155449%	One in 46
	Hurricane grey	158.85, 127.42, 141.52	2.110820%	One in 47
	Pearl	233.03, 232.73, 236.96	1.993587%	One in 50
	Slime green	82.22, 100.51, 86.53	1.877974%	One in 53
	Grey	159.25, 168.81, 147.58	1.866112%	One in 53
	Sand red	142.43, 117.19, 125.14	1.644322%	One in 60
	Artichoke	146.18, 166.15, 148.55	1.599249%	One in 62
	Silver	142.24, 171.54, 173.07	1.556062%	One in 64
	Fossil	164.30, 163.29, 180.67	1.508439%	One in 66
	Flint	108.72, 105.82, 88.74	1.382108%	One in 72
	Lily white	236.43, 232.08, 233.81	1.252599%	One in 79
	Sand yellow	140.09, 147.14, 122.94	1.183323%	One in 84
	Earth blue	57.66, 59.99, 76.36	1.156545%	One in 86
	Dark stone grey	100.67, 96.66, 118.32	1.134502%	One in 88
	Faded green	117.11, 144.92, 114.84	1.084275%	One in 92
	Cadet blue	150.84, 180.06, 178.37	0.925500%	One in 108
	Pine Cone	109.43, 87.19, 90.92	0.882928%	One in 113
	Medium stone grey	176.01, 155.93, 163.93	0.880791%	One in 113
	Linen	169.19, 128.39, 128.82	0.873657%	One in 114
	Sand blue	133.48, 135.50, 155.76	0.828806%	One in 120
	Grime	122.78, 133.37, 106.70	0.778585%	One in 128
	Lilac	114.10, 101.28, 141.03	0.472943%	One in 211
	Fog	211.94, 211.77, 220.71	0.445895%	One in 224
	Earth yellow	92.66, 95.98, 75.12	0.421937%	One in 237
	Reddish lilac	125.09, 112.82, 158.77	0.344553%	One in 290
	Really black	30.59, 25.20, 24.99	0.332505%	One in 300
	Laurel green	170.00, 190.34, 166.89	0.306585%	One in 326
	Copper	147.30, 94.66, 119.44	0.293565%	One in 340
	Cocoa	66.63, 56.73, 39.95	0.279018%	One in 358
	Mulberry	77.42, 54.86, 82.81	0.188278%	One in 531
	Moss	135.40, 159.49, 120.47	0.164397%	One in 608
	Seashell	225.46, 218.67, 219.33	0.114083%	One in 876
	Brown	127.30, 93.03, 87.55	0.100533%	One in 994
	Lavender	144.25, 97.38, 145.49	0.094846%	One in 1054
	Bright violet	107.88, 85.60, 127.71	0.071935%	One in 1390
	Medium bluish violet	100.11, 114.93, 142.56	0.049258%	One in 2030
	Bright reddish lilac	139.02, 90.10, 127.41	0.044880%	One in 2228
	Plum	123.45, 84.02, 122.30	0.038177%	One in 2619
	Shamrock	92.10, 133.15, 96.47	0.037096%	One in 2695
	Tawny	129.88, 83.54, 90.03	0.034197%	One in 2924
	Bronze	112.06, 108.75, 65.78	0.031130%	One in 3212
	Earth orange	101.10, 81.99, 58.87	0.030521%	One in 3276
	Steel blue	81.43, 124.99, 122.72	0.027276%	One in 3666
	Bright bluish violet	93.23, 85.81, 136.81	0.026786%	One in 3733
	Medium lilac	70.67, 64.04, 106.63	0.026098%	One in 3831
	Medium green	162.58, 178.80, 147.38	0.017836%	One in 5606
	Storm blue	64.91, 84.86, 110.26	0.017640%	One in 5668
	Parsley green	57.54, 99.29, 62.56	0.012026%	One in 8315
	Beige	185.85, 187.57, 161.56	0.010828%	One in 9235
	Light lilac	180.31, 178.43, 198.11	0.009875%	One in 10126
	Bright reddish violet	131.67, 83.60, 117.52	0.008236%	One in 12141
	Dark green	54.16, 93.97, 70.12	0.006221%	One in 16074
	Light bluish green	185.58, 201.04, 203.88	0.005138%	One in 19462
	Turquoise	126.90, 168.57, 166.88	0.003795%	One in 26350
	Royal blue	77.54, 106.69, 128.04	0.003074%	One in 32530
	Reddish brown	109.40, 64.78, 66.17	0.002577%	One in 38804
	Sea green	53.40, 94.31, 65.33	0.001122%	One in 89126
	Burgundy	112.06, 65.22, 68.99	0.000217%	One in 460829
	Bright green	85.13, 137.56, 92.63	0.000204%	One in 490196

Debug Colors

A debug part, with the BrickColor "Deep orange".

Older versions of Grassy Landscape spawned random BrickColors instead of using a color spectrum. Colors outside the spawnable spectrum are referred to as "debug colors", since they used an unfinished algorithm for debugging purposes (i.e. to get the rest of the game working first). Since there is currently no save system, and all debug colors have been removed from the game, it is no longer possible to encounter a part color outside of the spectrum.

"Rare BrickColors"

When generating colors, the game will refuse to generate any color that happens to be a "rare BrickColor". The list of rare BrickColors is below:

Visual	Name	Reason
	Lig. Yellowich orange	Typo
	Light green (Mint)	Parenthesis
	Phosph. White	Cool name
	Transparent	Transparent
	Tr. Red	Transparent
	Tr. Lg blue	Transparent
	Tr. Blue	Transparent
	Tr. Yellow	Transparent
	Tr. Flu. Reddish orange	Transparent
	Tr. Green	Transparent
	Tr. Flu. Green	Transparent
	Tr. Brown	Transparent
	Tr. Medi. reddish violet	Transparent
	Tr. Bright bluish violet	Transparent
	Tr. Flu. Blue	Transparent
	Tr. Flu. Yellow	Transparent
	Tr. Flu. Red	Transparent
	Red flip/flop	Flip/flop
	Yellow flip/flop	Flip/flop
	Silver flip/flop	Flip/flop
	Sand blue metallic	Metallic
	Sand violet metallic	Metallic
	Sand yellow metallic	Metallic
	Dark grey metallic	Metallic
	Black metallic	Metallic
	Light grey metallic	Metallic
	Gun metallic	Metallic
	Lemon metalic	Bkerr's favorite color

If the algorithm generates a color that is "rare", it will simply re-roll until it lands on one that isn't. Most likely, if someone has a part with one of these colors, it was obtained from an event or someone with the debug GUI.