RegionIO/internal/worldgen/structure_manager.go

50 lines
1.7 KiB
Go

package worldgen
// PlaceStructures places any structure pieces that overlap the chunk at (cx, cz).
func PlaceStructures(cw ChunkWriter, od *OverworldDensity, cx, cz int32, seed int64, surfTop *[16][16]int, biomeName *[16][16]string) {
const spacing = 32 // chunk grid spacing for villages
const radius = 2 // max chunk radius a village spans
for dx := -radius; dx <= radius; dx++ {
for dz := -radius; dz <= radius; dz++ {
originCx := int(cx) + dx
originCz := int(cz) + dz
// Village every 32x32 chunks
if originCx%spacing == 0 && originCz%spacing == 0 {
t := GetTemplate("plains_small_house_1")
if t != nil {
// Deterministically evaluate the surface height at the origin so the structure
// is flush with the ground and consistent across all chunks.
baseY := EvaluateHeight(od, originCx*16+8, originCz*16+8)
// Only place if it's above sea level (so we don't spawn houses in the ocean)
if baseY >= 63 {
// Offset by -1 so the floor embeds into the grass, rather than floating on it.
t.Place(cw, cx, cz, originCx*16+8, baseY-1, originCz*16+8)
}
}
}
}
}
}
// EvaluateHeight computes the top solid block Y coordinate at (wx, wz).
func EvaluateHeight(od *OverworldDensity, wx, wz int) int {
interp := make([]float64, len(od.Interpolated))
// Binary search or linear scan. A linear scan from 120 down to 0 is fast enough.
for y := 120; y >= -64; y-- {
ctx := FunctionContext{X: float64(wx), Y: float64(y), Z: float64(wz)}
// Since we don't have the cell grid, we just evaluate the interpolated nodes directly!
for n, node := range od.Interpolated {
interp[n] = node.Inner.Compute(ctx)
}
ctx = ctx.WithInterp(interp)
if od.Final.Compute(ctx) > 0 {
return y
}
}
return 64
}