fix spawn checks at biome edge

common/src/main/java/com/dfsek/terra/api/structures/world/AirCheck.java

@@ -5,8 +5,8 @@ import com.dfsek.terra.api.platform.TerraPlugin;
 import com.dfsek.terra.api.platform.world.World;
 import com.dfsek.terra.api.world.generation.GenerationPhase;
 import com.dfsek.terra.biome.UserDefinedBiome;
+import com.dfsek.terra.biome.grid.master.TerraBiomeGrid;
 import com.dfsek.terra.config.templates.BiomeTemplate;
-import com.dfsek.terra.generation.config.WorldGenerator;
 
 public class AirCheck extends SpawnCheck {
     public AirCheck(World world, TerraPlugin main) {
@@ -16,10 +16,10 @@ public class AirCheck extends SpawnCheck {
     @Override
     public boolean check(int x, int y, int z) {
         TerraWorld tw = main.getWorld(world);
-        UserDefinedBiome b = (UserDefinedBiome) tw.getGrid().getBiome(x, z, GenerationPhase.POPULATE);
+        TerraBiomeGrid g = tw.getGrid();
+        UserDefinedBiome b = (UserDefinedBiome) g.getBiome(x, z, GenerationPhase.POPULATE);
         BiomeTemplate c = b.getConfig();
         if(y <= c.getSeaLevel()) return false;
-        double elevation = ((WorldGenerator) b.getGenerator(world)).getElevation(x, z);
+        return sample(x, y, z, g) <= 0;
-        return b.getGenerator(world).getNoise(x, y, z) + elevation <= 0;
     }
 }

common/src/main/java/com/dfsek/terra/api/structures/world/LandCheck.java

@@ -3,9 +3,6 @@ package com.dfsek.terra.api.structures.world;
 import com.dfsek.terra.TerraWorld;
 import com.dfsek.terra.api.platform.TerraPlugin;
 import com.dfsek.terra.api.platform.world.World;
-import com.dfsek.terra.api.world.generation.GenerationPhase;
-import com.dfsek.terra.biome.UserDefinedBiome;
-import com.dfsek.terra.generation.config.WorldGenerator;
 
 public class LandCheck extends SpawnCheck {
     public LandCheck(World world, TerraPlugin main) {
@@ -15,8 +12,6 @@ public class LandCheck extends SpawnCheck {
     @Override
     public boolean check(int x, int y, int z) {
         TerraWorld tw = main.getWorld(world);
-        UserDefinedBiome b = (UserDefinedBiome) tw.getGrid().getBiome(x, z, GenerationPhase.POPULATE);
+        return sample(x, y, z, tw.getGrid()) > 0;
-        double elevation = ((WorldGenerator) b.getGenerator(world)).getElevation(x, z);
-        return b.getGenerator(world).getNoise(x, y, z) + elevation > 0;
     }
 }

common/src/main/java/com/dfsek/terra/api/structures/world/OceanCheck.java

@@ -5,8 +5,8 @@ import com.dfsek.terra.api.platform.TerraPlugin;
 import com.dfsek.terra.api.platform.world.World;
 import com.dfsek.terra.api.world.generation.GenerationPhase;
 import com.dfsek.terra.biome.UserDefinedBiome;
+import com.dfsek.terra.biome.grid.master.TerraBiomeGrid;
 import com.dfsek.terra.config.templates.BiomeTemplate;
-import com.dfsek.terra.generation.config.WorldGenerator;
 
 public class OceanCheck extends SpawnCheck {
     public OceanCheck(World world, TerraPlugin main) {
@@ -16,10 +16,10 @@ public class OceanCheck extends SpawnCheck {
     @Override
     public boolean check(int x, int y, int z) {
         TerraWorld tw = main.getWorld(world);
-        UserDefinedBiome b = (UserDefinedBiome) tw.getGrid().getBiome(x, z, GenerationPhase.POPULATE);
+        TerraBiomeGrid grid = tw.getGrid();
+        UserDefinedBiome b = (UserDefinedBiome) grid.getBiome(x, z, GenerationPhase.POPULATE);
         BiomeTemplate c = b.getConfig();
         if(y > c.getSeaLevel()) return false;
-        double elevation = ((WorldGenerator) b.getGenerator(world)).getElevation(x, z);
+        return sample(x, y, z, grid) <= 0;
-        return b.getGenerator(world).getNoise(x, y, z) + elevation <= 0;
     }
 }

common/src/main/java/com/dfsek/terra/api/structures/world/SpawnCheck.java

@@ -2,16 +2,35 @@ package com.dfsek.terra.api.structures.world;
 
 import com.dfsek.terra.api.platform.TerraPlugin;
 import com.dfsek.terra.api.platform.world.World;
+import com.dfsek.terra.biome.grid.master.TerraBiomeGrid;
+import com.dfsek.terra.generation.math.Sampler;
+import net.jafama.FastMath;
+
+import java.util.LinkedHashMap;
+import java.util.Map;
 
 public abstract class SpawnCheck {
     protected final World world;
     protected final TerraPlugin main;
+    private final Map<Long, Sampler> cache;
 
     protected SpawnCheck(World world, TerraPlugin main) {
         this.world = world;
         this.main = main;
+        cache = new LinkedHashMap<Long, Sampler>() {
+            @Override
+            protected boolean removeEldestEntry(Map.Entry<Long, Sampler> eldest) {
+                return size() > main.getTerraConfig().getCheckCache();
+            }
+        };
     }
 
     public abstract boolean check(int x, int y, int z);
 
+    protected double sample(int x, int y, int z, TerraBiomeGrid grid) {
+        int cx = FastMath.floorDiv(x, 16);
+        int cz = FastMath.floorDiv(z, 16);
+        long key = (((long) cx) << 32) | (cz & 0xffffffffL);
+        return cache.computeIfAbsent(key, k -> new Sampler(cx, cz, grid, world, 4, 8)).sample(x - (cx << 4), y, z - (cz << 4));
+    }
 }

common/src/main/java/com/dfsek/terra/config/base/PluginConfig.java

@@ -42,6 +42,10 @@ public class PluginConfig implements ConfigTemplate {
     @Default
     private int structureCache = 128;
 
+    @Value("cache.checks")
+    @Default
+    private int checkCache = 128;
+
     @Value("dump-default")
     @Default
     private boolean dumpDefaultConfig = true;
@@ -90,4 +94,8 @@ public class PluginConfig implements ConfigTemplate {
     public int getStructureCache() {
         return structureCache;
     }
+
+    public int getCheckCache() {
+        return checkCache;
+    }
 }