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Noise generator in separate class

This commit is contained in:
Forwolk
2018-08-05 17:15:55 +03:00
parent 5d3487d5ec
commit 15b1ff7370
2 changed files with 58 additions and 51 deletions

View File

@@ -0,0 +1,57 @@
package mc.world.generated_world.generator;
import lombok.RequiredArgsConstructor;
import lombok.extern.slf4j.Slf4j;
import static mc.world.generated_world.WorldConstants.WORLD_REGION_SIZE;
@Slf4j
@RequiredArgsConstructor
public class NoiseGenerator {
private int[] perm = new int[WORLD_REGION_SIZE];
private double[] gradsX = new double[WORLD_REGION_SIZE];
private double[] gradsY = new double[WORLD_REGION_SIZE];
private final int seed;
void init() {
for (int i = 0; i < WORLD_REGION_SIZE; ++i) {
int other = rand(i) % (i + 1);
if (i > other)
perm[i] = perm[other];
perm[other] = i;
gradsX[i] = Math.cos(2.0f * Math.PI * i / WORLD_REGION_SIZE);
gradsY[i] = Math.sin(2.0f * Math.PI * i / WORLD_REGION_SIZE);
}
log.debug("Noise generator is initialized");
}
double f(double t) {
t = Math.abs(t);
return t >= 1.0f ? 0.0f : 1.0f -
(3.0f - 2.0f * t) * t * t;
}
private double surflet(double x, double y, double gradX, double gradY) {
return f(x) * f(y) * (gradX * x + gradY * y);
}
double noise(double x, double y) {
float result = 0.0f;
int cellX = (int)(x);
int cellY = (int)(y);
int mask = WORLD_REGION_SIZE - 1;
for (int gridY = cellY; gridY <= cellY + 1; ++gridY)
for (int gridX = cellX; gridX <= cellX + 1; ++gridX) {
int hash = perm[(perm[gridX & mask] + gridY) & mask];
result += surflet(x - gridX, y - gridY,
gradsX[hash], gradsY[hash]);
}
return (result + 1) / 2;
}
private int rand(int i) {
int x = (i * i) % WORLD_REGION_SIZE;
int y = (i + i * x) % WORLD_REGION_SIZE;
return (int) (Integer.MAX_VALUE * SeedRandomGenerator.random(x, y, seed));
}
}

View File

@@ -80,7 +80,7 @@ public class SeedBasedWorldGenerator implements WorldGenerator {
return 40960 + x; return 40960 + x;
} }
public void generate() { private void generate() {
log.debug("Starting generating region [{}, {}] for world '{}' with seed '{}'", region.getX(), region.getZ(), world.getWorldId(), world.getSeed()); log.debug("Starting generating region [{}, {}] for world '{}' with seed '{}'", region.getX(), region.getZ(), world.getWorldId(), world.getSeed());
noiseGenerator = new NoiseGenerator(world.getSeed()); noiseGenerator = new NoiseGenerator(world.getSeed());
@@ -388,54 +388,4 @@ public class SeedBasedWorldGenerator implements WorldGenerator {
} }
} }
@RequiredArgsConstructor
private class NoiseGenerator {
int mask = WORLD_REGION_SIZE - 1;
int[] perm = new int[WORLD_REGION_SIZE];
double[] gradsX = new double[WORLD_REGION_SIZE];
double[] gradsY = new double[WORLD_REGION_SIZE];
private final int seed;
void init() {
for (int i = 0; i < WORLD_REGION_SIZE; ++i) {
int other = rand(i) % (i + 1);
if (i > other)
perm[i] = perm[other];
perm[other] = i;
gradsX[i] = Math.cos(2.0f * Math.PI * i / WORLD_REGION_SIZE);
gradsY[i] = Math.sin(2.0f * Math.PI * i / WORLD_REGION_SIZE);
}
log.debug("Noise generator is initialized");
}
double f(double t) {
t = Math.abs(t);
return t >= 1.0f ? 0.0f : 1.0f -
(3.0f - 2.0f * t) * t * t;
}
double surflet(double x, double y, double gradX, double gradY) {
return f(x) * f(y) * (gradX * x + gradY * y);
}
double noise(double x, double y) {
float result = 0.0f;
int cellX = (int)(x);
int cellY = (int)(y);
for (int gridY = cellY; gridY <= cellY + 1; ++gridY)
for (int gridX = cellX; gridX <= cellX + 1; ++gridX) {
int hash = perm[(perm[gridX & mask] + gridY) & mask];
result += surflet(x - gridX, y - gridY,
gradsX[hash], gradsY[hash]);
}
return (result + 1) / 2;
}
int rand(int i) {
int x = (i * i) % WORLD_REGION_SIZE;
int y = (i + i * x) % WORLD_REGION_SIZE;
return (int) (Integer.MAX_VALUE * SeedRandomGenerator.random(x, y, seed));
}
}
} }