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https://gitlab.com/veloren/veloren.git
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751 lines
28 KiB
Rust
751 lines
28 KiB
Rust
mod location;
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mod settlement;
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mod util;
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// Reexports
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pub use self::location::Location;
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pub use self::settlement::Settlement;
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use self::util::{
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cdf_irwin_hall, uniform_idx_as_vec2, uniform_noise, vec2_as_uniform_idx, InverseCdf,
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};
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use crate::{
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all::ForestKind,
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column::ColumnGen,
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generator::TownState,
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util::{seed_expan, FastNoise, Sampler, StructureGen2d},
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CONFIG,
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};
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use common::{
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terrain::{BiomeKind, TerrainChunkSize},
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vol::RectVolSize,
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};
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use noise::{
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BasicMulti, Billow, HybridMulti, MultiFractal, NoiseFn, RidgedMulti, Seedable, SuperSimplex,
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};
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use rand::{Rng, SeedableRng};
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use rand_chacha::ChaChaRng;
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use std::{
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collections::HashMap,
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f32,
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ops::{Add, Div, Mul, Neg, Sub},
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sync::Arc,
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};
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use vek::*;
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pub const WORLD_SIZE: Vec2<usize> = Vec2 { x: 1024, y: 1024 };
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/// Calculates the smallest distance along an axis (x, y) from an edge of
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/// the world. This value is maximal at WORLD_SIZE / 2 and minimized at the extremes
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/// (0 or WORLD_SIZE on one or more axes). It then divides the quantity by cell_size,
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/// so the final result is 1 when we are not in a cell along the edge of the world, and
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/// ranges between 0 and 1 otherwise (lower when the chunk is closer to the edge).
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fn map_edge_factor(posi: usize) -> f32 {
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uniform_idx_as_vec2(posi)
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.map2(WORLD_SIZE.map(|e| e as i32), |e, sz| {
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(sz / 2 - (e - sz / 2).abs()) as f32 / 16.0
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})
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.reduce_partial_min()
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.max(0.0)
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.min(1.0)
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}
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/// A structure that holds cached noise values and cumulative distribution functions for the input
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/// that led to those values. See the definition of InverseCdf for a description of how to
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/// interpret the types of its fields.
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struct GenCdf {
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humid_base: InverseCdf,
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temp_base: InverseCdf,
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alt_base: InverseCdf,
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chaos: InverseCdf,
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alt: InverseCdf,
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alt_no_seawater: InverseCdf,
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}
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pub(crate) struct GenCtx {
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pub turb_x_nz: SuperSimplex,
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pub turb_y_nz: SuperSimplex,
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pub chaos_nz: RidgedMulti,
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pub alt_nz: HybridMulti,
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pub hill_nz: SuperSimplex,
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pub temp_nz: SuperSimplex,
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// Fresh groundwater (currently has no effect, but should influence humidity)
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pub dry_nz: BasicMulti,
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// Humidity noise
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pub humid_nz: Billow,
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// Small amounts of noise for simulating rough terrain.
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pub small_nz: BasicMulti,
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pub rock_nz: HybridMulti,
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pub cliff_nz: HybridMulti,
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pub warp_nz: FastNoise,
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pub tree_nz: BasicMulti,
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pub cave_0_nz: SuperSimplex,
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pub cave_1_nz: SuperSimplex,
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pub structure_gen: StructureGen2d,
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pub region_gen: StructureGen2d,
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pub cliff_gen: StructureGen2d,
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pub fast_turb_x_nz: FastNoise,
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pub fast_turb_y_nz: FastNoise,
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pub town_gen: StructureGen2d,
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}
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pub struct WorldSim {
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pub seed: u32,
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pub(crate) chunks: Vec<SimChunk>,
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pub(crate) locations: Vec<Location>,
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pub(crate) gen_ctx: GenCtx,
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pub rng: ChaChaRng,
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}
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impl WorldSim {
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pub fn generate(seed: u32) -> Self {
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let mut rng = ChaChaRng::from_seed(seed_expan::rng_state(seed));
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let mut gen_ctx = GenCtx {
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turb_x_nz: SuperSimplex::new().set_seed(rng.gen()),
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turb_y_nz: SuperSimplex::new().set_seed(rng.gen()),
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chaos_nz: RidgedMulti::new().set_octaves(7).set_seed(rng.gen()),
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hill_nz: SuperSimplex::new().set_seed(rng.gen()),
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alt_nz: HybridMulti::new()
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.set_octaves(8)
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.set_persistence(0.1)
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.set_seed(rng.gen()),
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temp_nz: SuperSimplex::new().set_seed(rng.gen()),
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dry_nz: BasicMulti::new().set_seed(rng.gen()),
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small_nz: BasicMulti::new().set_octaves(2).set_seed(rng.gen()),
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rock_nz: HybridMulti::new().set_persistence(0.3).set_seed(rng.gen()),
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cliff_nz: HybridMulti::new().set_persistence(0.3).set_seed(rng.gen()),
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warp_nz: FastNoise::new(rng.gen()), //BasicMulti::new().set_octaves(3).set_seed(gen_seed()),
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tree_nz: BasicMulti::new()
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.set_octaves(12)
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.set_persistence(0.75)
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.set_seed(rng.gen()),
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cave_0_nz: SuperSimplex::new().set_seed(rng.gen()),
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cave_1_nz: SuperSimplex::new().set_seed(rng.gen()),
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structure_gen: StructureGen2d::new(rng.gen(), 32, 24),
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region_gen: StructureGen2d::new(rng.gen(), 400, 96),
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cliff_gen: StructureGen2d::new(rng.gen(), 80, 56),
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humid_nz: Billow::new()
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.set_octaves(12)
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.set_persistence(0.125)
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.set_frequency(1.0)
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// .set_octaves(6)
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// .set_persistence(0.5)
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.set_seed(rng.gen()),
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fast_turb_x_nz: FastNoise::new(rng.gen()),
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fast_turb_y_nz: FastNoise::new(rng.gen()),
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town_gen: StructureGen2d::new(rng.gen(), 2048, 1024),
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};
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// "Base" of the chunk, to be multiplied by CONFIG.mountain_scale (multiplied value is
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// from -0.25 * (CONFIG.mountain_scale * 1.1) to 0.25 * (CONFIG.mountain_scale * 0.9),
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// but value here is from -0.275 to 0.225).
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let alt_base = uniform_noise(|_, wposf| {
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Some(
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(gen_ctx.alt_nz.get((wposf.div(12_000.0)).into_array()) as f32)
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.sub(0.1)
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.mul(0.25),
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)
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});
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// chaos produces a value in [0.1, 1.24]. It is a meta-level factor intended to reflect how
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// "chaotic" the region is--how much weird stuff is going on on this terrain.
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let chaos = uniform_noise(|_posi, wposf| {
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// From 0 to 1.6, but the distribution before the max is from -1 and 1, so there is a
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// 50% chance that hill will end up at 0.
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let hill = (0.0
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+ gen_ctx
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.hill_nz
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.get((wposf.div(1_500.0)).into_array())
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.mul(1.0) as f32
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+ gen_ctx
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.hill_nz
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.get((wposf.div(400.0)).into_array())
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.mul(0.3) as f32)
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.add(0.3)
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.max(0.0);
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Some(
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(gen_ctx.chaos_nz.get((wposf.div(3_000.0)).into_array()) as f32)
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.add(1.0)
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.mul(0.5)
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// [0, 1] * [0.25, 1] = [0, 1] (but probably towards the lower end)
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.mul(
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(gen_ctx.chaos_nz.get((wposf.div(6_000.0)).into_array()) as f32)
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.abs()
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.max(0.25)
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.min(1.0),
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)
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// Chaos is always increased by a little when we're on a hill (but remember that
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// hill is 0 about 50% of the time).
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// [0, 1] + 0.15 * [0, 1.6] = [0, 1.24]
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.add(0.2 * hill)
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// We can't have *no* chaos!
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.max(0.1),
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)
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});
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// We ignore sea level because we actually want to be relative to sea level here and want
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// things in CONFIG.mountain_scale units, but otherwise this is a correct altitude
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// calculation. Note that this is using the "unadjusted" temperature.
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let alt = uniform_noise(|posi, wposf| {
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// This is the extension upwards from the base added to some extra noise from -1 to 1.
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// The extra noise is multiplied by alt_main (the mountain part of the extension)
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// clamped to [0.25, 1], and made 60% larger (so the extra noise is between [-1.6, 1.6],
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// and the final noise is never more than 160% or less than 40% of the original noise,
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// depending on altitude).
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// Adding this to alt_main thus yields a value between -0.4 (if alt_main = 0 and
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// gen_ctx = -1) and 2.6 (if alt_main = 1 and gen_ctx = 1). When the generated small_nz
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// value hits -0.625 the value crosses 0, so most of the points are above 0.
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//
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// Then, we add 1 and divide by 2 to get a value between 0.3 and 1.8.
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let alt_main = {
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// Extension upwards from the base. A positive number from 0 to 1 curved to be
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// maximal at 0. Also to be multiplied by CONFIG.mountain_scale.
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let alt_main = (gen_ctx.alt_nz.get((wposf.div(2_000.0)).into_array()) as f32)
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.abs()
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.powf(1.35);
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(0.0 + alt_main
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+ (gen_ctx.small_nz.get((wposf.div(300.0)).into_array()) as f32)
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.mul(alt_main.max(0.25))
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.mul(0.3)
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.add(1.0)
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.mul(0.5))
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};
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// Now we can compute the final altitude using chaos.
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// We multiply by chaos clamped to [0.1, 1.24] to get a value between 0.03 and 2.232 for
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// alt_pre, then multiply by CONFIG.mountain_scale and add to the base and sea level to
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// get an adjusted value, then multiply the whole thing by map_edge_factor
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// (TODO: compute final bounds).
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Some((alt_base[posi].1 + alt_main.mul(chaos[posi].1)).mul(map_edge_factor(posi)))
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});
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// Check whether any tiles around this tile are not water (since Lerp will ensure that they
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// are included).
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let pure_water = |posi| {
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let pos = uniform_idx_as_vec2(posi);
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for x in pos.x - 1..=pos.x + 1 {
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for y in pos.y - 1..=pos.y + 1 {
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if x >= 0 && y >= 0 && x < WORLD_SIZE.x as i32 && y < WORLD_SIZE.y as i32 {
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let posi = vec2_as_uniform_idx(Vec2::new(x, y));
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if alt[posi].1.mul(CONFIG.mountain_scale) > 0.0 {
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return false;
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}
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}
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}
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}
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true
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};
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// A version of alt that is uniform over *non-seawater* (or land-adjacent seawater) chunks.
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let alt_no_seawater = uniform_noise(|posi, _wposf| {
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if pure_water(posi) {
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None
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} else {
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Some(alt[posi].1)
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}
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});
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// -1 to 1.
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let temp_base = uniform_noise(|posi, wposf| {
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if pure_water(posi) {
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None
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} else {
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Some(gen_ctx.temp_nz.get((wposf.div(12000.0)).into_array()) as f32)
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}
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});
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// 0 to 1, hopefully.
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let humid_base = uniform_noise(|posi, wposf| {
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// Check whether any tiles around this tile are water.
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if pure_water(posi) {
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None
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} else {
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Some(
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(gen_ctx.humid_nz.get(wposf.div(1024.0).into_array()) as f32)
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.add(1.0)
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.mul(0.5),
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)
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}
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});
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let gen_cdf = GenCdf {
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humid_base,
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temp_base,
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alt_base,
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chaos,
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alt,
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alt_no_seawater,
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};
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let mut chunks = Vec::new();
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for i in 0..WORLD_SIZE.x * WORLD_SIZE.y {
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chunks.push(SimChunk::generate(i, &mut gen_ctx, &gen_cdf));
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}
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let mut this = Self {
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seed: seed,
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chunks,
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locations: Vec::new(),
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gen_ctx,
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rng,
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};
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this.seed_elements();
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this
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}
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/// Prepare the world for simulation
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pub fn seed_elements(&mut self) {
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let mut rng = self.rng.clone();
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let cell_size = 16;
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let grid_size = WORLD_SIZE / cell_size;
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let loc_count = 100;
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let mut loc_grid = vec![None; grid_size.product()];
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let mut locations = Vec::new();
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// Seed the world with some locations
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for _ in 0..loc_count {
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let cell_pos = Vec2::new(
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self.rng.gen::<usize>() % grid_size.x,
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self.rng.gen::<usize>() % grid_size.y,
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);
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let wpos = (cell_pos * cell_size + cell_size / 2)
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.map2(TerrainChunkSize::RECT_SIZE, |e, sz: u32| {
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e as i32 * sz as i32 + sz as i32 / 2
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});
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locations.push(Location::generate(wpos, &mut rng));
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loc_grid[cell_pos.y * grid_size.x + cell_pos.x] = Some(locations.len() - 1);
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}
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// Find neighbours
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let mut loc_clone = locations
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.iter()
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.map(|l| l.center)
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.enumerate()
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.collect::<Vec<_>>();
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for i in 0..locations.len() {
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let pos = locations[i].center;
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loc_clone.sort_by_key(|(_, l)| l.distance_squared(pos));
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loc_clone.iter().skip(1).take(2).for_each(|(j, _)| {
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locations[i].neighbours.insert(*j);
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locations[*j].neighbours.insert(i);
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});
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}
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// Simulate invasion!
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let invasion_cycles = 25;
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for _ in 0..invasion_cycles {
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for i in 0..grid_size.x {
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for j in 0..grid_size.y {
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if loc_grid[j * grid_size.x + i].is_none() {
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const R_COORDS: [i32; 5] = [-1, 0, 1, 0, -1];
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let idx = self.rng.gen::<usize>() % 4;
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let loc = Vec2::new(i as i32 + R_COORDS[idx], j as i32 + R_COORDS[idx + 1])
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.map(|e| e as usize);
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loc_grid[j * grid_size.x + i] =
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loc_grid.get(loc.y * grid_size.x + loc.x).cloned().flatten();
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}
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}
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}
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}
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// Place the locations onto the world
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let gen = StructureGen2d::new(self.seed, cell_size as u32, cell_size as u32 / 2);
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for i in 0..WORLD_SIZE.x {
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for j in 0..WORLD_SIZE.y {
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let chunk_pos = Vec2::new(i as i32, j as i32);
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let block_pos = Vec2::new(
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chunk_pos.x * TerrainChunkSize::RECT_SIZE.x as i32,
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chunk_pos.y * TerrainChunkSize::RECT_SIZE.y as i32,
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);
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let _cell_pos = Vec2::new(i / cell_size, j / cell_size);
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// Find the distance to each region
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let near = gen.get(chunk_pos);
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let mut near = near
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.iter()
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.map(|(pos, seed)| RegionInfo {
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chunk_pos: *pos,
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block_pos: pos
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.map2(TerrainChunkSize::RECT_SIZE, |e, sz: u32| e * sz as i32),
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dist: (pos - chunk_pos).map(|e| e as f32).magnitude(),
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seed: *seed,
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})
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.collect::<Vec<_>>();
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// Sort regions based on distance
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near.sort_by(|a, b| a.dist.partial_cmp(&b.dist).unwrap());
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let nearest_cell_pos = near[0].chunk_pos.map(|e| e as usize) / cell_size;
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self.get_mut(chunk_pos).unwrap().location = loc_grid
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.get(nearest_cell_pos.y * grid_size.x + nearest_cell_pos.x)
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.cloned()
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.unwrap_or(None)
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.map(|loc_idx| LocationInfo { loc_idx, near });
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let town_size = 200;
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let in_town = self
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.get(chunk_pos)
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.unwrap()
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.location
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.as_ref()
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.map(|l| {
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locations[l.loc_idx].center.distance_squared(block_pos)
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< town_size * town_size
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})
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.unwrap_or(false);
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if in_town {
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self.get_mut(chunk_pos).unwrap().spawn_rate = 0.0;
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}
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}
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}
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// Stage 2 - towns!
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let mut maybe_towns = HashMap::new();
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for i in 0..WORLD_SIZE.x {
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for j in 0..WORLD_SIZE.y {
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let chunk_pos = Vec2::new(i as i32, j as i32);
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let wpos = chunk_pos.map2(Vec2::from(TerrainChunkSize::RECT_SIZE), |e, sz: u32| {
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e * sz as i32 + sz as i32 / 2
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});
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let near_towns = self.gen_ctx.town_gen.get(wpos);
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let town = near_towns
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.iter()
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.min_by_key(|(pos, _seed)| wpos.distance_squared(*pos));
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if let Some((pos, _)) = town {
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let maybe_town = maybe_towns
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.entry(*pos)
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.or_insert_with(|| {
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TownState::generate(*pos, &mut ColumnGen::new(self), &mut rng)
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.map(|t| Arc::new(t))
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})
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.as_mut()
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// Only care if we're close to the town
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.filter(|town| {
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Vec2::from(town.center()).distance_squared(wpos)
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< town.radius().add(64).pow(2)
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})
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.cloned();
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self.get_mut(chunk_pos).unwrap().structures.town = maybe_town;
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}
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}
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}
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self.rng = rng;
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self.locations = locations;
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}
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pub fn get(&self, chunk_pos: Vec2<i32>) -> Option<&SimChunk> {
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if chunk_pos
|
||
.map2(WORLD_SIZE, |e, sz| e >= 0 && e < sz as i32)
|
||
.reduce_and()
|
||
{
|
||
Some(&self.chunks[vec2_as_uniform_idx(chunk_pos)])
|
||
} else {
|
||
None
|
||
}
|
||
}
|
||
|
||
pub fn get_wpos(&self, wpos: Vec2<i32>) -> Option<&SimChunk> {
|
||
self.get(
|
||
wpos.map2(Vec2::from(TerrainChunkSize::RECT_SIZE), |e, sz: u32| {
|
||
e / sz as i32
|
||
}),
|
||
)
|
||
}
|
||
|
||
pub fn get_mut(&mut self, chunk_pos: Vec2<i32>) -> Option<&mut SimChunk> {
|
||
if chunk_pos
|
||
.map2(WORLD_SIZE, |e, sz| e >= 0 && e < sz as i32)
|
||
.reduce_and()
|
||
{
|
||
Some(&mut self.chunks[vec2_as_uniform_idx(chunk_pos)])
|
||
} else {
|
||
None
|
||
}
|
||
}
|
||
|
||
pub fn get_base_z(&self, chunk_pos: Vec2<i32>) -> Option<f32> {
|
||
self.get(chunk_pos).and_then(|_| {
|
||
(0..2)
|
||
.map(|i| (0..2).map(move |j| (i, j)))
|
||
.flatten()
|
||
.map(|(i, j)| {
|
||
self.get(chunk_pos + Vec2::new(i, j))
|
||
.map(|c| c.get_base_z())
|
||
})
|
||
.flatten()
|
||
.fold(None, |a: Option<f32>, x| a.map(|a| a.min(x)).or(Some(x)))
|
||
})
|
||
}
|
||
|
||
pub fn get_interpolated<T, F>(&self, pos: Vec2<i32>, mut f: F) -> Option<T>
|
||
where
|
||
T: Copy + Default + Add<Output = T> + Mul<f32, Output = T>,
|
||
F: FnMut(&SimChunk) -> T,
|
||
{
|
||
let pos = pos.map2(TerrainChunkSize::RECT_SIZE, |e, sz: u32| {
|
||
e as f64 / sz as f64
|
||
});
|
||
|
||
let cubic = |a: T, b: T, c: T, d: T, x: f32| -> T {
|
||
let x2 = x * x;
|
||
|
||
// Catmull-Rom splines
|
||
let co0 = a * -0.5 + b * 1.5 + c * -1.5 + d * 0.5;
|
||
let co1 = a + b * -2.5 + c * 2.0 + d * -0.5;
|
||
let co2 = a * -0.5 + c * 0.5;
|
||
let co3 = b;
|
||
|
||
co0 * x2 * x + co1 * x2 + co2 * x + co3
|
||
};
|
||
|
||
let mut x = [T::default(); 4];
|
||
|
||
for (x_idx, j) in (-1..3).enumerate() {
|
||
let y0 = f(self.get(pos.map2(Vec2::new(j, -1), |e, q| e.max(0.0) as i32 + q))?);
|
||
let y1 = f(self.get(pos.map2(Vec2::new(j, 0), |e, q| e.max(0.0) as i32 + q))?);
|
||
let y2 = f(self.get(pos.map2(Vec2::new(j, 1), |e, q| e.max(0.0) as i32 + q))?);
|
||
let y3 = f(self.get(pos.map2(Vec2::new(j, 2), |e, q| e.max(0.0) as i32 + q))?);
|
||
|
||
x[x_idx] = cubic(y0, y1, y2, y3, pos.y.fract() as f32);
|
||
}
|
||
|
||
Some(cubic(x[0], x[1], x[2], x[3], pos.x.fract() as f32))
|
||
}
|
||
}
|
||
|
||
pub struct SimChunk {
|
||
pub chaos: f32,
|
||
pub alt_base: f32,
|
||
pub alt: f32,
|
||
pub temp: f32,
|
||
pub humidity: f32,
|
||
pub rockiness: f32,
|
||
pub is_cliffs: bool,
|
||
pub near_cliffs: bool,
|
||
pub tree_density: f32,
|
||
pub forest_kind: ForestKind,
|
||
pub spawn_rate: f32,
|
||
pub location: Option<LocationInfo>,
|
||
|
||
pub structures: Structures,
|
||
}
|
||
|
||
#[derive(Copy, Clone)]
|
||
pub struct RegionInfo {
|
||
pub chunk_pos: Vec2<i32>,
|
||
pub block_pos: Vec2<i32>,
|
||
pub dist: f32,
|
||
pub seed: u32,
|
||
}
|
||
|
||
#[derive(Clone)]
|
||
pub struct LocationInfo {
|
||
pub loc_idx: usize,
|
||
pub near: Vec<RegionInfo>,
|
||
}
|
||
|
||
#[derive(Clone)]
|
||
pub struct Structures {
|
||
pub town: Option<Arc<TownState>>,
|
||
}
|
||
|
||
impl SimChunk {
|
||
fn generate(posi: usize, gen_ctx: &mut GenCtx, gen_cdf: &GenCdf) -> Self {
|
||
let pos = uniform_idx_as_vec2(posi);
|
||
let wposf = (pos * TerrainChunkSize::RECT_SIZE.map(|e| e as i32)).map(|e| e as f64);
|
||
|
||
let (_, alt_base) = gen_cdf.alt_base[posi];
|
||
let map_edge_factor = map_edge_factor(posi);
|
||
let (_, chaos) = gen_cdf.chaos[posi];
|
||
let (humid_uniform, _) = gen_cdf.humid_base[posi];
|
||
let (_, alt_pre) = gen_cdf.alt[posi];
|
||
let (alt_uniform, _) = gen_cdf.alt_no_seawater[posi];
|
||
let (temp_uniform, _) = gen_cdf.temp_base[posi];
|
||
|
||
// Take the weighted average of our randomly generated base humidity, the scaled
|
||
// negative altitude, and other random variable (to add some noise) to yield the
|
||
// final humidity. Note that we are using the "old" version of chaos here.
|
||
const HUMID_WEIGHTS: [f32; 2] = [1.0, 1.0];
|
||
let humidity = cdf_irwin_hall(&HUMID_WEIGHTS, [humid_uniform, 1.0 - alt_uniform]);
|
||
|
||
// We also correlate temperature negatively with altitude using different weighting than we
|
||
// use for humidity.
|
||
const TEMP_WEIGHTS: [f32; 2] = [2.0, 1.0];
|
||
let temp = cdf_irwin_hall(&TEMP_WEIGHTS, [temp_uniform, 1.0 - alt_uniform])
|
||
// Convert to [-1, 1]
|
||
.sub(0.5)
|
||
.mul(2.0);
|
||
|
||
let alt_base = alt_base.mul(CONFIG.mountain_scale);
|
||
let alt = CONFIG
|
||
.sea_level
|
||
.mul(map_edge_factor)
|
||
.add(alt_pre.mul(CONFIG.mountain_scale));
|
||
|
||
let cliff = gen_ctx.cliff_nz.get((wposf.div(2048.0)).into_array()) as f32 + chaos * 0.2;
|
||
|
||
// Logistic regression. Make sure x ∈ (0, 1).
|
||
let logit = |x: f32| x.ln() - x.neg().ln_1p();
|
||
// 0.5 + 0.5 * tanh(ln(1 / (1 - 0.1) - 1) / (2 * (sqrt(3)/pi)))
|
||
let logistic_2_base = 3.0f32.sqrt().mul(f32::consts::FRAC_2_PI);
|
||
// Assumes μ = 0, σ = 1
|
||
let logistic_cdf = |x: f32| x.div(logistic_2_base).tanh().mul(0.5).add(0.5);
|
||
|
||
// No trees in the ocean or with zero humidity (currently)
|
||
let tree_density = if alt <= CONFIG.sea_level + 5.0 {
|
||
0.0
|
||
} else {
|
||
let tree_density = (gen_ctx.tree_nz.get((wposf.div(1024.0)).into_array()) as f32)
|
||
.mul(1.5)
|
||
.add(1.0)
|
||
.mul(0.5)
|
||
.mul(1.2 - chaos * 0.95)
|
||
.add(0.05)
|
||
.max(0.0)
|
||
.min(1.0);
|
||
// Tree density should go (by a lot) with humidity.
|
||
if humidity <= 0.0 || tree_density <= 0.0 {
|
||
0.0
|
||
} else if humidity >= 1.0 || tree_density >= 1.0 {
|
||
1.0
|
||
} else {
|
||
// Weighted logit sum.
|
||
logistic_cdf(logit(humidity) + 0.5 * logit(tree_density))
|
||
}
|
||
// rescale to (-0.95, 0.95)
|
||
.sub(0.5)
|
||
.mul(0.95)
|
||
.add(0.5)
|
||
};
|
||
|
||
Self {
|
||
chaos,
|
||
alt_base,
|
||
alt,
|
||
temp,
|
||
humidity,
|
||
rockiness: (gen_ctx.rock_nz.get((wposf.div(1024.0)).into_array()) as f32)
|
||
.sub(0.1)
|
||
.mul(1.3)
|
||
.max(0.0),
|
||
is_cliffs: cliff > 0.5 && alt > CONFIG.sea_level + 5.0,
|
||
near_cliffs: cliff > 0.2,
|
||
tree_density,
|
||
forest_kind: if temp > 0.0 {
|
||
if temp > CONFIG.desert_temp {
|
||
if humidity > CONFIG.jungle_hum {
|
||
// Forests in desert temperatures with extremely high humidity
|
||
// should probably be different from palm trees, but we use them
|
||
// for now.
|
||
ForestKind::Palm
|
||
} else if humidity > CONFIG.forest_hum {
|
||
ForestKind::Palm
|
||
} else if humidity > CONFIG.desert_hum {
|
||
// Low but not desert humidity, so we should really have some other
|
||
// terrain...
|
||
ForestKind::Savannah
|
||
} else {
|
||
ForestKind::Savannah
|
||
}
|
||
} else if temp > CONFIG.tropical_temp {
|
||
if humidity > CONFIG.jungle_hum {
|
||
ForestKind::Mangrove
|
||
} else if humidity > CONFIG.forest_hum {
|
||
// NOTE: Probably the wrong kind of tree for this climate.
|
||
ForestKind::Oak
|
||
} else if humidity > CONFIG.desert_hum {
|
||
// Low but not desert... need something besides savannah.
|
||
ForestKind::Savannah
|
||
} else {
|
||
ForestKind::Savannah
|
||
}
|
||
} else {
|
||
if humidity > CONFIG.jungle_hum {
|
||
// Temperate climate with jungle humidity...
|
||
// https://en.wikipedia.org/wiki/Humid_subtropical_climates are often
|
||
// densely wooded and full of water. Semitropical rainforests, basically.
|
||
// For now we just treet them like other rainforests.
|
||
ForestKind::Oak
|
||
} else if humidity > CONFIG.forest_hum {
|
||
// Moderate climate, moderate humidity.
|
||
ForestKind::Oak
|
||
} else if humidity > CONFIG.desert_hum {
|
||
// With moderate temperature and low humidity, we should probably see
|
||
// something different from savannah, but oh well...
|
||
ForestKind::Savannah
|
||
} else {
|
||
ForestKind::Savannah
|
||
}
|
||
}
|
||
} else {
|
||
// For now we don't take humidity into account for cold climates (but we really
|
||
// should!) except that we make sure we only have snow pines when there is snow.
|
||
if temp <= CONFIG.snow_temp && humidity > CONFIG.forest_hum {
|
||
ForestKind::SnowPine
|
||
} else if humidity > CONFIG.desert_hum {
|
||
ForestKind::Pine
|
||
} else {
|
||
// Should really have something like tundra.
|
||
ForestKind::Pine
|
||
}
|
||
},
|
||
spawn_rate: 1.0,
|
||
location: None,
|
||
|
||
structures: Structures { town: None },
|
||
}
|
||
}
|
||
|
||
pub fn get_base_z(&self) -> f32 {
|
||
self.alt - self.chaos * 50.0 - 16.0
|
||
}
|
||
|
||
pub fn get_name(&self, world: &WorldSim) -> Option<String> {
|
||
if let Some(loc) = &self.location {
|
||
Some(world.locations[loc.loc_idx].name().to_string())
|
||
} else {
|
||
None
|
||
}
|
||
}
|
||
|
||
pub fn get_biome(&self) -> BiomeKind {
|
||
if self.alt < CONFIG.sea_level {
|
||
BiomeKind::Ocean
|
||
} else if self.chaos > 0.6 {
|
||
BiomeKind::Mountain
|
||
} else if self.temp > CONFIG.desert_temp {
|
||
BiomeKind::Desert
|
||
} else if self.temp < CONFIG.snow_temp {
|
||
BiomeKind::Snowlands
|
||
} else if self.tree_density > 0.65 {
|
||
BiomeKind::Forest
|
||
} else {
|
||
BiomeKind::Grassland
|
||
}
|
||
}
|
||
}
|