#include "Generator.hpp"
+#include "BlockType.hpp"
+#include "BlockTypeRegistry.hpp"
#include "Chunk.hpp"
+#include "../graphics/glm.hpp"
#include "../rand/OctaveNoise.hpp"
-#include <glm/glm.hpp>
-
namespace blank {
+namespace {
+
+struct Candidate {
+ const BlockType *type;
+ float threshold;
+ Candidate(const BlockType *type, float threshold)
+ : type(type), threshold(threshold) { }
+};
+
+std::vector<Candidate> candidates;
+
+}
+
Generator::Generator(const Config &config) noexcept
-: solidNoise(config.seed)
-, typeNoise(config.seed)
-, stretch(1.0f/config.stretch)
-, solid_threshold(config.solid_threshold)
-// TODO: stable dynamic generator configuration
-, space(0)
-, light(13)
-, solids({ 1, 4, 7, 10 }) {
+: config(config)
+, types()
+, min_solidity(2.0f)
+, solidity_noise(config.seed ^ config.solidity.seed_mask)
+, humidity_noise(config.seed ^ config.humidity.seed_mask)
+, temperature_noise(config.seed ^ config.temperature.seed_mask)
+, richness_noise(config.seed ^ config.richness.seed_mask)
+, random_noise(config.seed ^ config.randomness.seed_mask) {
}
+void Generator::LoadTypes(const BlockTypeRegistry ®) {
+ types.clear();
+ min_solidity = 2.0f;
+ for (const BlockType &type : reg) {
+ if (type.generate) {
+ types.push_back(&type);
+ if (type.solidity.Min() < min_solidity) {
+ min_solidity = type.solidity.Min();
+ }
+ }
+ }
+ candidates.reserve(types.size());
+}
-void Generator::operator ()(Chunk &chunk) const noexcept {
- Chunk::Pos pos(chunk.Position());
- glm::vec3 coords(pos * Chunk::Extent());
- for (int z = 0; z < Chunk::depth; ++z) {
- for (int y = 0; y < Chunk::height; ++y) {
- for (int x = 0; x < Chunk::width; ++x) {
- Block::Pos block_pos(x, y, z);
- glm::vec3 gen_pos = (coords + block_pos) * stretch;
- float val = OctaveNoise(solidNoise, coords + block_pos, 3, 0.5f, stretch, 2.0f);
- if (val > solid_threshold) {
- int type_val = int((typeNoise(gen_pos) + 1.0f) * solids.size()) % solids.size();
- chunk.SetBlock(block_pos, Block(solids[type_val]));
- } else {
- chunk.SetBlock(block_pos, Block(space));
+namespace {
+
+struct Interpolation {
+ /// sample points for interpolation
+ /// given coordinates should be the absoloute position of the chunk's (0,0,0) block
+ Interpolation(
+ const SimplexNoise &noise,
+ const glm::vec3 &base,
+ const Generator::Config::NoiseParam &conf
+ ) noexcept {
+ for (int z = 0; z < 5; ++z) {
+ for (int y = 0; y < 5; ++y) {
+ for (int x = 0; x < 5; ++x) {
+ samples[z][y][x] = OctaveNoise(
+ noise,
+ base + (glm::vec3(x, y, z) * 4.0f),
+ conf.octaves,
+ conf.persistence,
+ conf.frequency,
+ conf.amplitude,
+ conf.growth
+ );
}
}
}
}
- unsigned int random = 263167 * pos.x + 2097593 * pos.y + 426389 * pos.z;
- for (int index = 0; index < Chunk::size; ++index) {
- if (chunk.IsSurface(index)) {
- random = random * 666649 + 7778777;
- if ((random % 32) == 0) {
- chunk.SetBlock(index, Block(light));
+ float samples[5][5][5];
+};
+
+struct Parameters {
+ glm::ivec3 a;
+ glm::ivec3 b;
+ glm::ivec3 d;
+};
+
+struct Detail {
+ float humidity;
+ float temperature;
+ float richness;
+ float randomness;
+};
+
+}
+
+struct Generator::ValueField {
+
+ Interpolation solidity;
+ Interpolation humidity;
+ Interpolation temperature;
+ Interpolation richness;
+ Interpolation randomness;
+
+ static Parameters GetParams(const glm::ivec3 &pos) noexcept {
+ Parameters p;
+ p.a = pos / 4;
+ p.b = p.a + 1;
+ p.d = pos % 4;
+ return p;
+ }
+
+ static float Interpolate(const Interpolation &i, const Parameters &p) noexcept {
+ constexpr float A[4] = { 1.0f, 0.75f, 0.5f, 0.25f };
+ constexpr float B[4] = { 0.0f, 0.25f, 0.5f, 0.75f };
+ const float l1[4] = {
+ i.samples[p.a.z][p.a.y][p.a.x] * A[p.d.x] + i.samples[p.a.z][p.a.y][p.b.x] * B[p.d.x],
+ i.samples[p.a.z][p.b.y][p.a.x] * A[p.d.x] + i.samples[p.a.z][p.b.y][p.b.x] * B[p.d.x],
+ i.samples[p.b.z][p.a.y][p.a.x] * A[p.d.x] + i.samples[p.b.z][p.a.y][p.b.x] * B[p.d.x],
+ i.samples[p.b.z][p.b.y][p.a.x] * A[p.d.x] + i.samples[p.b.z][p.b.y][p.b.x] * B[p.d.x],
+ };
+ const float l2[2] = {
+ l1[0] * A[p.d.y] + l1[1] * B[p.d.y],
+ l1[2] * A[p.d.y] + l1[3] * B[p.d.y],
+ };
+ return l2[0] * A[p.d.z] + l2[1] * B[p.d.z];
+ }
+
+};
+
+void Generator::operator ()(Chunk &chunk) const noexcept {
+ ExactLocation::Fine coords(chunk.Position() * ExactLocation::Extent());
+ coords += 0.5f;
+ ValueField field {
+ { solidity_noise, coords, config.solidity },
+ { humidity_noise, coords, config.humidity },
+ { temperature_noise, coords, config.temperature },
+ { richness_noise, coords, config.richness },
+ { random_noise, coords, config.randomness },
+ };
+ for (int z = 0; z < Chunk::side; ++z) {
+ for (int y = 0; y < Chunk::side; ++y) {
+ for (int x = 0; x < Chunk::side; ++x) {
+ chunk.SetBlock(RoughLocation::Fine(x, y, z), Generate(field, RoughLocation::Fine(x, y, z)));
}
}
}
+ chunk.SetGenerated();
+}
+
+Block Generator::Generate(const ValueField &field, const glm::ivec3 &pos) const noexcept {
+ Parameters params(ValueField::GetParams(pos));
+ float solidity = ValueField::Interpolate(field.solidity, params);
+ if (solidity < min_solidity) {
+ return Block(0);
+ }
+ float humidity = ValueField::Interpolate(field.humidity, params);
+ float temperature = ValueField::Interpolate(field.temperature, params);
+ float richness = ValueField::Interpolate(field.richness, params);
+
+ candidates.clear();
+ float total = 0.0f;
+ for (const BlockType *type : types) {
+ if (!type->solidity.Valid(solidity)) continue;
+ if (!type->humidity.Valid(humidity)) continue;
+ if (!type->temperature.Valid(temperature)) continue;
+ if (!type->richness.Valid(richness)) continue;
+ float solidity_match = type->solidity.Map(solidity);
+ float humidity_match = type->humidity.Map(humidity);
+ float temperature_match = type->temperature.Map(temperature);
+ float richness_match = type->richness.Map(richness);
+ float chance = (solidity_match + humidity_match + temperature_match + richness_match) * type->commonness;
+ total += chance;
+ candidates.emplace_back(type, total);
+ }
+ if (candidates.empty()) {
+ return Block(0);
+ }
+ float random = ValueField::Interpolate(field.randomness, params);
+ // as weird as it sounds, but this is faster tham glm::fract and generates a
+ // better distribution than (transformed variants of) erf, erfc, atan, and smoothstep
+ if (random < 0.0f) random += 1.0f;
+ float value = random * total;
+ // TODO: change to binary search
+ for (const Candidate &cand : candidates) {
+ if (value < cand.threshold) {
+ return Block(cand.type->id);
+ }
+ }
+ // theoretically, this should never happen
+ return Block(candidates.back().type->id);
}
}