MC-117412Heightmap min value not set when loading chunk from NBT
The bug
Note: The following is based on decompiled code, using MCP naming.
The minimum heightmap value for a chunk is currently set when the heightmap is populated either by chunk generation on the server, or by a chunk data packet being received by the client. However, it is not set when a chunk is read from NBT (see AnvilChunkLoader#readChunkFromNBT()).
This means that server-side, any chunk not freshly generated will have a heightmap minimum of 0.
The main effect of this is that lighting checks performed by Chunk#recheckGaps() will call World#checkLightFor() for all y-values between 0 and the heightmap value for that column (+1), instead of a reduced range.
Possible fix
The heightMapMinimum field should be updated when the heightmap is set in Chunk#setHeightMap(). For example:
public void setHeightMap(int[] newHeightMap) { if (this.heightMap.length != newHeightMap.length) { LOGGER.warn("Could not set level chunk heightmap, array length is {} instead of {}", newHeightMap.length, this.heightMap.length); } else { System.arraycopy(newHeightMap, 0, this.heightMap, 0, this.heightMap.length); // *update heightmap min value here* } }
Created Issue:
Heightmap min value not set when loading chunk from NBT
The issue:
Note: The following is based on decompiled code, using MCP naming.
The minimum heightmap value for a chunk is currently set when the heightmap is populated either by chunk generation on the server, or by a chunk data packet being received by the client. However, it is not set when a chunk is read from NBT (see AnvilChunkLoader#readChunkFromNBT()).
This means that server-side, any chunk not freshly generated will have a heightmap minimum of 0.
The main effect of this is that lighting checks performed by Chunk#recheckGaps() will call World#checkLightFor() for all y-values between 0 and the heightmap value for that column (+1), instead of a reduced range.Possible fix:
The heightMapMinimum field should be updated when the heightmap is set in Chunk#setHeightMap(). For example:
public void setHeightMap(int[] newHeightMap) { if (this.heightMap.length != newHeightMap.length) { LOGGER.warn("Could not set level chunk heightmap, array length is {} instead of {}", new Object[] {Integer.valueOf(newHeightMap.length), Integer.valueOf(this.heightMap.length)}); } else { System.arraycopy(newHeightMap, 0, this.heightMap, 0, this.heightMap.length); // *update heightmap min value here* } }
The issue:
Note: The following is based on decompiled code, using MCP naming.
The minimum heightmap value for a chunk is currently set when the heightmap is populated either by chunk generation on the server, or by a chunk data packet being received by the client. However, it is not set when a chunk is read from NBT (see AnvilChunkLoader#readChunkFromNBT()).
This means that server-side, any chunk not freshly generated will have a heightmap minimum of 0.
The main effect of this is that lighting checks performed by Chunk#recheckGaps() will call World#checkLightFor() for all y-values between 0 and the heightmap value for that column (+1), instead of a reduced range.Possible fix:
The heightMapMinimum field should be updated when the heightmap is set in Chunk#setHeightMap(). For example:
public void setHeightMap(int[] newHeightMap) { if (this.heightMap.length != newHeightMap.length) { LOGGER.warn("Could not set level chunk heightmap, array length is {} instead of {}", new Object[] {Integer.valueOf(newHeightMap.length), Integer.valueOf(this.heightMap.length)}); } else { System.arraycopy(newHeightMap, 0, this.heightMap, 0, this.heightMap.length); // *update heightmap min value here* } }The issue:
Note: The following is based on decompiled code, using MCP naming.
The minimum heightmap value for a chunk is currently set when the heightmap is populated either by chunk generation on the server, or by a chunk data packet being received by the client. However, it is not set when a chunk is read from NBT (see AnvilChunkLoader#readChunkFromNBT()).
This means that server-side, any chunk not freshly generated will have a heightmap minimum of 0.
The main effect of this is that lighting checks performed by Chunk#recheckGaps() will call World#checkLightFor() for all y-values between 0 and the heightmap value for that column (+1), instead of a reduced range.Possible fix:
The heightMapMinimum field should be updated when the heightmap is set in Chunk#setHeightMap(). For example:
public void setHeightMap(int[] newHeightMap) { if (this.heightMap.length != newHeightMap.length) { LOGGER.warn("Could not set level chunk heightmap, array length is {} instead of {}" , newHeightMap.length, this.heightMap.length); } else { System.arraycopy(newHeightMap, 0, this.heightMap, 0, this.heightMap.length); // *update heightmap min value here* } }
![[Mod] Michael Wobst](../../../data/avatars/users/37868.png){kind=small}
The
issue:Note: The following is based on decompiled code, using MCP naming.
The minimum heightmap value for a chunk is currently set when the heightmap is populated either by chunk generation on the server, or by a chunk data packet being received by the client. However, it is not set when a chunk is read from NBT (see AnvilChunkLoader#readChunkFromNBT()).
This means that server-side, any chunk not freshly generated will have a heightmap minimum of 0.
The main effect of this is that lighting checks performed by Chunk#recheckGaps() will call World#checkLightFor() for all y-values between 0 and the heightmap value for that column (+1), instead of a reduced range.Possible fix
:The heightMapMinimum field should be updated when the heightmap is set in Chunk#setHeightMap(). For example:
public void setHeightMap(int[] newHeightMap) { if (this.heightMap.length != newHeightMap.length) { LOGGER.warn("Could not set level chunk heightmap, array length is {} instead of {}", newHeightMap.length, this.heightMap.length); } else { System.arraycopy(newHeightMap, 0, this.heightMap, 0, this.heightMap.length); // *update heightmap min value here* } }The bug
Note: The following is based on decompiled code, using MCP naming.
The minimum heightmap value for a chunk is currently set when the heightmap is populated either by chunk generation on the server, or by a chunk data packet being received by the client. However, it is not set when a chunk is read from NBT (see AnvilChunkLoader#readChunkFromNBT()).
This means that server-side, any chunk not freshly generated will have a heightmap minimum of 0.
The main effect of this is that lighting checks performed by Chunk#recheckGaps() will call World#checkLightFor() for all y-values between 0 and the heightmap value for that column (+1), instead of a reduced range.Possible fix
The heightMapMinimum field should be updated when the heightmap is set in Chunk#setHeightMap(). For example:
public void setHeightMap(int[] newHeightMap) { if (this.heightMap.length != newHeightMap.length) { LOGGER.warn("Could not set level chunk heightmap, array length is {} instead of {}", newHeightMap.length, this.heightMap.length); } else { System.arraycopy(newHeightMap, 0, this.heightMap, 0, this.heightMap.length); // *update heightmap min value here* } }
![[Mojang] Nathan Adams](../../../data/assets/gravatar/dinnerbone.png){kind=small}
Does this still apply to 1.14.4 or 1.15-pre1?
![[Mod] tryashtar](../../../data/avatars/users/41963.png){kind=small}
Can this still be reproduced in the latest 1.16 development snapshot?