RegionIO/internal/worldgen/biome_test.go

205 lines
6.4 KiB
Go

package worldgen
import (
"math"
"math/rand"
"strconv"
"testing"
)
func TestQuantize(t *testing.T) {
cases := []struct {
v float64
want int64
}{
{0.0, 0},
{0.5, 5000},
{-1.0, -10000},
{1.0, 10000},
{-0.15, -1500},
{0.55, 5500},
{0.00005, 1},
{-0.00005, 0},
}
for _, c := range cases {
if got := quantize(c.v); got != c.want {
t.Errorf("quantize(%v) = %d, want %d", c.v, got, c.want)
}
}
}
func TestParameterTableDistanceOffsetAndTies(t *testing.T) {
pointRange := func(value int64) [AxisCount]ClimateRange {
var ranges [AxisCount]ClimateRange
for i := range ranges {
ranges[i] = ClimateRange{Min: 0, Max: 0}
}
ranges[0] = ClimateRange{Min: value, Max: value}
return ranges
}
point := TargetPoint{Temperature: 5}
table := NewParameterTable([]BiomeParameter{
{Name: "offset-wins", Ranges: pointRange(0), Offset: 0}, // fitness 25
{Name: "range-loses", Ranges: pointRange(5), Offset: 10}, // fitness 100
{Name: "same-fitness-later", Ranges: pointRange(10), Offset: 0}, // fitness 25
})
if got := table.FindBiome(point); got != "offset-wins" {
t.Fatalf("FindBiome = %q, want first minimum-fitness entry", got)
}
if got := fitDistance(point, pointRange(5), 0); got != 0 {
t.Fatalf("point inside exact range has fitness %d", got)
}
}
func TestParameterTableIndexMatchesLinearSearch(t *testing.T) {
random := rand.New(rand.NewSource(12345))
params := make([]BiomeParameter, 2048)
for i := range params {
params[i].Name = "biome-" + strconv.Itoa(i)
for axis := 0; axis < AxisCount; axis++ {
lo := random.Int63n(40001) - 20000
hi := lo + random.Int63n(5001)
params[i].Ranges[axis] = ClimateRange{Min: lo, Max: hi}
}
params[i].Offset = random.Int63n(1001) - 500
}
// Duplicate an entry under a later name to exercise the original-order tie
// break across separate leaves of the search tree.
params[len(params)-1] = params[0]
params[len(params)-1].Name = "later duplicate"
table := NewParameterTable(params)
for sample := 0; sample < 5000; sample++ {
point := TargetPoint{
Temperature: random.Int63n(50001) - 25000,
Humidity: random.Int63n(50001) - 25000,
Continentalness: random.Int63n(50001) - 25000,
Erosion: random.Int63n(50001) - 25000,
Depth: random.Int63n(50001) - 25000,
Weirdness: random.Int63n(50001) - 25000,
}
want, bestDist := "", int64(math.MaxInt64)
for _, param := range params {
if distance := fitDistance(point, param.Ranges, param.Offset); distance < bestDist {
want, bestDist = param.Name, distance
}
}
if got := table.FindBiome(point); got != want {
t.Fatalf("sample %d: indexed FindBiome = %q, linear = %q", sample, got, want)
}
}
}
func TestFitnessVectorsAgainstVanillaRuntime(t *testing.T) {
zero := [AxisCount]ClimateRange{}
temperatureRange := zero
temperatureRange[0] = ClimateRange{Min: 0, Max: 10}
depthWeirdness := zero
depthWeirdness[4] = ClimateRange{Min: 20, Max: 20}
depthWeirdness[5] = ClimateRange{Min: 30, Max: 30}
for _, vector := range []struct {
name string
point TargetPoint
ranges [AxisCount]ClimateRange
offset int64
want int64
}{
{"inside", TargetPoint{Temperature: 5}, temperatureRange, 0, 0},
{"below", TargetPoint{Temperature: -3}, temperatureRange, 0, 9},
{"above", TargetPoint{Temperature: 14}, temperatureRange, 0, 16},
{"offset", TargetPoint{Temperature: 5}, temperatureRange, 7, 49},
{"depth-weirdness-order", TargetPoint{Depth: 23, Weirdness: 35}, depthWeirdness, 0, 34},
} {
if got := fitDistance(vector.point, vector.ranges, vector.offset); got != vector.want {
t.Errorf("%s fitness = %d, want vanilla runtime %d", vector.name, got, vector.want)
}
}
}
// TestFitDistanceZero confirms identical points are zero-distance and distinct
// points are positive; the exact value is not asserted to stay robust to
// representation choices.
func TestFitDistance(t *testing.T) {
a := NewTargetPoint(0, 0, 0, 0, 0, 0)
ranges := [AxisCount]ClimateRange{}
if got := fitDistance(a, ranges, 0); got != 0 {
t.Errorf("fitDistance(a,a) = %d, want 0", got)
}
b := NewTargetPoint(1, 0, 0, 0, 0, 0)
// 10000^2 per axis of difference.
if got := fitDistance(b, ranges, 0); got != 10000*10000 {
t.Errorf("fitDistance for 1.0 temp diff = %d, want %d", got, int64(10000*10000))
}
}
// TestRangeContains checks the half-open [min, max) band used by the finder.
func TestRangeContains(t *testing.T) {
r := ClimateRange{Min: 0, Max: 100}
if !r.contains(0) {
t.Error("min should be inclusive")
}
if !r.contains(100) {
t.Error("max should be inclusive")
}
if !r.contains(50) {
t.Error("interior should contain")
}
}
func TestContainsAllUsesVanillaAxisOrder(t *testing.T) {
var ranges [AxisCount]ClimateRange
for i := range ranges {
ranges[i] = ClimateRange{Min: 0, Max: 0}
}
ranges[4] = ClimateRange{Min: 20, Max: 20}
ranges[5] = ClimateRange{Min: 30, Max: 30}
if !containsAll(ranges, TargetPoint{Depth: 20, Weirdness: 30}) {
t.Fatal("depth/weirdness ranges were not matched in vanilla order")
}
if containsAll(ranges, TargetPoint{Depth: 30, Weirdness: 20}) {
t.Fatal("accepted swapped depth/weirdness axes")
}
}
// TestSampleColumnDeterministic verifies the same seed/coords give the same
// biome and a different seed gives (almost certainly) a different one.
func TestSampleColumnDeterministic(t *testing.T) {
od1, err := LoadOverworldFinalDensity(1)
if err != nil {
t.Fatalf("load seed 1: %v", err)
}
od2, err := LoadOverworldFinalDensity(99999)
if err != nil {
t.Fatalf("load seed 99999: %v", err)
}
p1a := SampleColumn(od1, 63, 100, 200)
p1b := SampleColumn(od1, 63, 100, 200)
if p1a != p1b {
t.Error("same seed/coords should produce identical TargetPoint")
}
p2 := SampleColumn(od2, 63, 100, 200)
if p1a == p2 {
// Not a hard failure (collisions exist), but flag it for inspection.
t.Log("note: different seed produced identical climate point at (100,200)")
}
}
// TestClimateFieldsLoaded confirms the loader populates all six climate axes
// from the noise_router (regression guard for the loader change).
func TestClimateFieldsLoaded(t *testing.T) {
od, err := LoadOverworldFinalDensity(42)
if err != nil {
t.Fatalf("load: %v", err)
}
if od.Final == nil {
t.Fatal("Final density not loaded")
}
dfs := []DensityFunction{od.Temperature, od.Humidity, od.Continentalness, od.Erosion, od.Weirdness, od.Depth}
for i, df := range dfs {
if df == nil {
t.Errorf("climate axis %d not loaded", i)
}
}
}