fix: fix block entity can be spawned in negative-y space

AllayMC · Oct 1, 2024 · 07557bd · 07557bd
1 parent 409cf34
commit 07557bd
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Showing 2 changed files with 11 additions and 7 deletions.
diff --git a/api/src/main/java/org/allaymc/api/utils/HashUtils.java b/api/src/main/java/org/allaymc/api/utils/HashUtils.java
@@ -139,7 +139,7 @@ public int getZFromHashXZ(long hashXZ) {
 
     public int hashChunkXYZ(int x, int y, int z) {
         Preconditions.checkArgument(x >= 0 && x <= 15);
-        Preconditions.checkArgument(y >= 0 && y <= 16777216);
+        Preconditions.checkArgument(y >= -8388608 && y <= 8388607);
         Preconditions.checkArgument(z >= 0 && z <= 15);
         //Make sure x and z are in the range of 0-15
         x &= 0xF;  //4 bits
@@ -149,7 +149,7 @@ public int hashChunkXYZ(int x, int y, int z) {
         //Place x in the top 4 digits
         result |= (x << 28);
         //Place y in the middle 24 bits
-        result |= (y & 0xFFFFFF) << 4;
+        result |= ((y + 8388608) & 0xFFFFFF) << 4;
         //Place z in the lowest 4 digits
         result |= z;
         return result;
@@ -174,7 +174,7 @@ public int getXFromHashChunkXYZ(int encoded) {
      * @return The value of y.
      */
     public int getYFromHashChunkXYZ(int encoded) {
-        return (encoded >>> 4) & 0xFFFFFF;
+        return ((encoded >>> 4) & 0xFFFFFF) - 8388608;
     }
 
     /**

diff --git a/server/src/test/java/org/allaymc/server/utils/HashUtilsTest.java b/server/src/test/java/org/allaymc/server/utils/HashUtilsTest.java
@@ -66,13 +66,17 @@ public void testGetXZFromHashXZ() {
     @Test
     public void testHashChunkXYZ() {
         int l = HashUtils.hashChunkXYZ(8, 64, 8);
-        Assertions.assertEquals(-2147482616, l);
+        Assertions.assertEquals(-2013264888, l);
+
+        int l2 = HashUtils.hashChunkXYZ(8, -64, 8);
+        Assertions.assertEquals(-2013266936, l2);
     }
 
     @Test
     public void testGetXYZFromHashChunkXYZ() {
-        Assertions.assertEquals(8, HashUtils.getXFromHashChunkXYZ(-2147482616));
-        Assertions.assertEquals(64, HashUtils.getYFromHashChunkXYZ(-2147482616));
-        Assertions.assertEquals(8, HashUtils.getZFromHashChunkXYZ(-2147482616));
+        Assertions.assertEquals(8, HashUtils.getXFromHashChunkXYZ(-2013264888));
+        Assertions.assertEquals(64, HashUtils.getYFromHashChunkXYZ(-2013264888));
+        Assertions.assertEquals(-64, HashUtils.getYFromHashChunkXYZ(-2013266936));
+        Assertions.assertEquals(8, HashUtils.getZFromHashChunkXYZ(-2013264888));
     }
 }