Files
strom/mc/gen/biome_noise.go
T
2026-07-11 23:08:03 +02:00

103 lines
3.3 KiB
Go

package gen
import (
"math"
"github.com/admin-else/strom/mc/data"
)
type NoiseParam int
const (
NoiseParamTemperature NoiseParam = iota
NoiseParamHumidity
NoiseParamContinentalNess
NoiseParamErosion
NoiseParamShift
NoiseParamWeirdness
)
type NoiseParamMapV struct {
A []float64
S string
O int
}
var NoiseParamMap = map[NoiseParam]NoiseParamMapV{
NoiseParamShift: {A: []float64{1, 1, 1, 0}, S: "minecraft:offset", O: -3},
NoiseParamTemperature: {A: []float64{1.5, 0, 1, 0, 0, 0}, S: "minecraft:temperature", O: -10},
NoiseParamHumidity: {A: []float64{1, 1, 0, 0, 0, 0}, S: "minecraft:vegetation", O: -8},
NoiseParamContinentalNess: {A: []float64{1, 1, 2, 2, 2, 1, 1, 1, 1}, S: "minecraft:continentalness", O: -9},
NoiseParamErosion: {A: []float64{1, 1, 0, 1, 1}, S: "minecraft:erosion", O: -9},
NoiseParamWeirdness: {A: []float64{1, 2, 1, 0, 0, 0}, S: "minecraft:ridge", O: -7},
}
func initClimateSeed(n NoiseParam, x Xoroshiro, large bool, nmax int) DoublePerlin {
v := NoiseParamMap[n]
s := v.S
omin := v.O
if large && n != NoiseParamShift && n != NoiseParamWeirdness {
s += "_large"
omin -= 2
}
x.XorString(s)
return DoublePerlinFromXoroshiro(&x, v.A, omin, len(v.A), nmax)
}
type BiomeNoise struct {
Temperature, Humidity, ContinentalNess, Erosion, Shift, Weirdness DoublePerlin
}
func BiomeNoiseFromXoroshiro(x Xoroshiro, large bool) (v BiomeNoise) {
x = x.Split()
v.Temperature = initClimateSeed(NoiseParamTemperature, x, large, -1)
v.Humidity = initClimateSeed(NoiseParamHumidity, x, large, -1)
v.ContinentalNess = initClimateSeed(NoiseParamContinentalNess, x, large, -1)
v.Erosion = initClimateSeed(NoiseParamErosion, x, large, -1)
v.Shift = initClimateSeed(NoiseParamShift, x, large, -1)
v.Weirdness = initClimateSeed(NoiseParamWeirdness, x, large, -1)
return
}
func peaksAndValleys(weirdness float64) float64 {
return -(math.Abs(math.Abs(weirdness)-0.6666667) - 0.33333334) * 3.0
}
// Sample returns the raw climate parameters at the block position.
// The returned id is currently unused and always 0; use SampleBiome to resolve
// the biome from a multi-noise parameter list.
func (b BiomeNoise) Sample(x, y, z int) (t, h, c, e, d, w float64, combinedData [6]int64, id int) {
px := float64(x)
pz := float64(z)
px += b.Shift.Sample(px, 0, pz) * 4
pz += b.Shift.Sample(pz, float64(x), 0) * 4
c = b.ContinentalNess.Sample(px, 0, pz)
e = b.Erosion.Sample(px, 0, pz)
w = b.Weirdness.Sample(px, 0, pz)
t = b.Temperature.Sample(px, 0, pz)
h = b.Humidity.Sample(px, 0, pz)
off := float64(BiomeDepthSpline.Sample([]float32{float32(c), float32(e), float32(peaksAndValleys(w)), float32(w)})) + 0.015
d = 1.0 - (float64(y)*4)/128.0 - 83.0/160.0 + off
combinedData = [6]int64{
int64(float32(t) * 10000.0),
int64(float32(h) * 10000.0),
int64(float32(c) * 10000.0),
int64(float32(e) * 10000.0),
int64(float32(d) * 10000.0),
int64(float32(w) * 10000.0),
}
return
}
// SampleBiome samples the climate noise at (x, y, z) and resolves it through
// the supplied multi-noise parameter list. preset should be one of the
// data.MultiNoise* constants.
func (b BiomeNoise) SampleBiome(x, y, z int, mnd *data.MultiNoiseData, preset string) (string, error) {
_, _, _, _, _, _, combined, _ := b.Sample(x, y, z)
return mnd.Lookup(preset, combined[0], combined[1], combined[2], combined[3], combined[4], combined[5])
}