Improve cave-render detection and update default configs

BlueMapCore/src/main/java/de/bluecolored/bluemap/core/config/MapConfig.java

@@ -47,7 +47,8 @@ public class MapConfig implements MapSettings {
 	private float ambientLight;
 	private int worldSkyLight;
 	
-	private boolean renderCaves;
+	private int removeCavesBelowY;
+	private boolean caveDetectionUsesBlockLight;
 	
 	private Vector3i min, max;
 	private boolean renderEdges;
@@ -88,7 +89,8 @@ public class MapConfig implements MapSettings {
 		this.worldSkyLight = node.node("worldSkyLight").getInt(15);
 		
 		//renderCaves
-		this.renderCaves = node.node("renderCaves").getBoolean(false);
+		this.removeCavesBelowY = node.node("removeCavesBelowY").getInt(55);
+		this.caveDetectionUsesBlockLight = node.node("caveDetectionUsesBlockLight").getBoolean(false);
 
 		//bounds
 		int minX = node.node("minX").getInt(MapSettings.super.getMin().getX());
@@ -150,10 +152,16 @@ public class MapConfig implements MapSettings {
 		return worldSkyLight;
 	}
 
-	public boolean isRenderCaves() {
-		return renderCaves;
+	@Override
+	public int getRemoveCavesBelowY() {
+		return removeCavesBelowY;
 	}
-	
+
+	@Override
+	public boolean isCaveDetectionUsesBlockLight() {
+		return caveDetectionUsesBlockLight;
+	}
+
 	public boolean isIgnoreMissingLightData() {
 		return ignoreMissingLightData;
 	}
@@ -172,11 +180,6 @@ public class MapConfig implements MapSettings {
 	public int getLowresPointsPerLowresTile() {
 		return lowresPointsPerLowresTile;
 	}
-
-	@Override
-	public boolean isExcludeFacesWithoutSunlight() {
-		return !isRenderCaves();
-	}
 	
 	@Override
 	public Vector3i getMin() {

BlueMapCore/src/main/java/de/bluecolored/bluemap/core/map/hires/RenderSettings.java

@@ -32,11 +32,14 @@ public interface RenderSettings {
 	Vector3i DEFAULT_MAX = Vector3i.from(Integer.MAX_VALUE);
 
 	/**
-	 * Whether faces that have a sky-light-value of 0 will be rendered or not.
+	 * The y-level below which "caves" will not be rendered
 	 */
-	default boolean isExcludeFacesWithoutSunlight() {
-		return true;
-	}
+	int getRemoveCavesBelowY();
+
+	/**
+	 * If blocklight should be used instead of sky light to detect "caves"
+	 */
+	boolean isCaveDetectionUsesBlockLight();
 
 	/**
 	 * The minimum position of blocks to render
@@ -52,8 +55,14 @@ public interface RenderSettings {
 		return DEFAULT_MAX;
 	}
 
+	/**
+	 * The (default) ambient light of this world (0-1)
+	 */
 	float getAmbientLight();
 
+	/**
+	 * The sky-light level of this world (0-15)
+	 */
 	int getWorldSkyLight();
 	
 	/**

BlueMapCore/src/main/java/de/bluecolored/bluemap/core/map/hires/blockmodel/LiquidModelBuilder.java

@@ -95,7 +95,11 @@ public class LiquidModelBuilder {
 
 	private final Color tintcolor = new Color();
 	private void build() {
-		if (this.renderSettings.isExcludeFacesWithoutSunlight() && block.getSunLightLevel() == 0) return;
+		// filter out blocks that are in a "cave" that should not be rendered
+		if (
+				this.block.getY() < renderSettings.getRemoveCavesBelowY() &&
+				(renderSettings.isCaveDetectionUsesBlockLight() ? block.getBlockLightLevel() : block.getSunLightLevel()) == 0f
+		) return;
 		
 		int level = getLiquidLevel(blockState);
 		

BlueMapCore/src/main/java/de/bluecolored/bluemap/core/map/hires/blockmodel/ResourceModelBuilder.java

@@ -172,8 +172,11 @@ public class ResourceModelBuilder {
 		int sunLight = Math.max(blockLightData.getSkyLight(), facedLightData.getSkyLight());
 		int blockLight = Math.max(blockLightData.getBlockLight(), facedLightData.getBlockLight());
 
-		// filter out faces that are not sun-lighted
-		if (sunLight == 0f && renderSettings.isExcludeFacesWithoutSunlight()) return;
+		// filter out faces that are in a "cave" that should not be rendered
+		if (
+				this.block.getY() < renderSettings.getRemoveCavesBelowY() &&
+				(renderSettings.isCaveDetectionUsesBlockLight() ? blockLight : sunLight) == 0f
+		) return;
 
 		// initialize the faces
 		blockModel.initialize();

implementations/cli/src/main/resources/de/bluecolored/bluemap/render.conf

@@ -45,16 +45,31 @@ maps: [
 
 		# Defines the ambient light-strength that every block is recieving, regardless of the sunlight/blocklight.
 		# 0 is no ambient light, 1 is fully lighted.
-		# You can change this at any time.
+		# Changing this value requires a re-render of the map.
 		# Default is 0
 		ambientLight: 0
 
-		# If this is false, BlueMap tries to omit all blocks that are not visible from above-ground.
+		# Defines the skylight level that the sky of the world is emitting.
+        # This should always be equivalent to the maximum ingame sky-light for that world!
+        # If this is a normal overworld dimension, set this to 15 (max).
+        # If this is a normal nether or end dimension, set this to 0 (min).
+		# Changing this value requires a re-render of the map.
+        # Default is 15
+		worldSkyLight: 15
+
+		# BlueMap tries to omit all blocks that are below this Y-level and are not visible from above-ground.
 		# More specific: Block-Faces that have a sunlight/skylight value of 0 are removed.
 		# This improves the performance of the map on slower devices by a lot, but might cause some blocks to disappear that should normally be visible.
 		# Changing this value requires a re-render of the map.
-		# Default is false
-		renderCaves: false
+		# Set to a very high value to remove caves everywhere (e.g. 10000)
+		# Set to a very low value to remove nothing and render all caves (e.g. -10000)
+		# Default is 55 (slightly below water-level)
+		removeCavesBelowY: 55
+
+		# With this value set to true, BlueMap uses the block-light value instead of the sky-light value to "detect caves".
+		# (See: removeCavesBelowY)
+        # Default is false
+        caveDetectionUsesBlockLight: false
 		
 		# With the below values you can limit the map-render.
 		# This can be used to ignore the nethers ceiling or render only a certain part of a world.
@@ -102,9 +117,10 @@ maps: [
 		
 		# We dont want a blue sky in the end
 		skyColor: "#080010"
-		
-		# In the end is no sky-light, so we need to enable this or we won't see anything.
-		renderCaves: true
+
+		# In the end is no sky-light, so we need to set this or we won't see anything.
+		removeCavesBelowY: -10000
+		worldSkyLight: 0
 		
 		# Same here, we don't want a dark map. But not completely lighted, so we see the effect of e.g torches.
 		ambientLight: 0.6
@@ -117,8 +133,9 @@ maps: [
 		world: "world/DIM-1"
 		
 		skyColor: "#290000"
-		
-		renderCaves: true
+		worldSkyLight: 0
+
+		removeCavesBelowY: -10000
 		ambientLight: 0.6
 		
 		# We slice the whole world at y:90 so every block above 90 will be air.

implementations/fabric-1.15.2/src/main/resources/de/bluecolored/bluemap/render.conf

@@ -45,16 +45,31 @@ maps: [
 
 		# Defines the ambient light-strength that every block is recieving, regardless of the sunlight/blocklight.
 		# 0 is no ambient light, 1 is fully lighted.
-		# You can change this at any time.
+		# Changing this value requires a re-render of the map.
 		# Default is 0
 		ambientLight: 0
 
-		# If this is false, BlueMap tries to omit all blocks that are not visible from above-ground.
+		# Defines the skylight level that the sky of the world is emitting.
+        # This should always be equivalent to the maximum ingame sky-light for that world!
+        # If this is a normal overworld dimension, set this to 15 (max).
+        # If this is a normal nether or end dimension, set this to 0 (min).
+		# Changing this value requires a re-render of the map.
+        # Default is 15
+		worldSkyLight: 15
+
+		# BlueMap tries to omit all blocks that are below this Y-level and are not visible from above-ground.
 		# More specific: Block-Faces that have a sunlight/skylight value of 0 are removed.
 		# This improves the performance of the map on slower devices by a lot, but might cause some blocks to disappear that should normally be visible.
 		# Changing this value requires a re-render of the map.
-		# Default is false
-		renderCaves: false
+		# Set to a very high value to remove caves everywhere (e.g. 10000)
+		# Set to a very low value to remove nothing and render all caves (e.g. -10000)
+		# Default is 55 (slightly below water-level)
+		removeCavesBelowY: 55
+
+		# With this value set to true, BlueMap uses the block-light value instead of the sky-light value to "detect caves".
+		# (See: removeCavesBelowY)
+        # Default is false
+        caveDetectionUsesBlockLight: false
 		
 		# With the below values you can limit the map-render.
 		# This can be used to ignore the nethers ceiling or render only a certain part of a world.
@@ -102,9 +117,10 @@ maps: [
 		
 		# We dont want a blue sky in the end
 		skyColor: "#080010"
-		
-		# In the end is no sky-light, so we need to enable this or we won't see anything.
-		renderCaves: true
+
+		# In the end is no sky-light, so we need to set this or we won't see anything.
+		removeCavesBelowY: -10000
+		worldSkyLight: 0
 		
 		# Same here, we don't want a dark map. But not completely lighted, so we see the effect of e.g torches.
 		ambientLight: 0.6
@@ -117,9 +133,10 @@ maps: [
 		world: "world/DIM-1"
 		
 		skyColor: "#290000"
-		
-		renderCaves: true
-		ambientLight: 0.6
+        worldSkyLight: 0
+
+        removeCavesBelowY: -10000
+        ambientLight: 0.6
 		
 		# We slice the whole world at y:90 so every block above 90 will be air.
 		# This way we don't render the nethers ceiling.

implementations/fabric-1.16.1/src/main/resources/de/bluecolored/bluemap/render.conf

@@ -45,16 +45,31 @@ maps: [
 
 		# Defines the ambient light-strength that every block is recieving, regardless of the sunlight/blocklight.
 		# 0 is no ambient light, 1 is fully lighted.
-		# You can change this at any time.
+		# Changing this value requires a re-render of the map.
 		# Default is 0
 		ambientLight: 0
 
-		# If this is false, BlueMap tries to omit all blocks that are not visible from above-ground.
+		# Defines the skylight level that the sky of the world is emitting.
+        # This should always be equivalent to the maximum ingame sky-light for that world!
+        # If this is a normal overworld dimension, set this to 15 (max).
+        # If this is a normal nether or end dimension, set this to 0 (min).
+		# Changing this value requires a re-render of the map.
+        # Default is 15
+		worldSkyLight: 15
+
+		# BlueMap tries to omit all blocks that are below this Y-level and are not visible from above-ground.
 		# More specific: Block-Faces that have a sunlight/skylight value of 0 are removed.
 		# This improves the performance of the map on slower devices by a lot, but might cause some blocks to disappear that should normally be visible.
 		# Changing this value requires a re-render of the map.
-		# Default is false
-		renderCaves: false
+		# Set to a very high value to remove caves everywhere (e.g. 10000)
+		# Set to a very low value to remove nothing and render all caves (e.g. -10000)
+		# Default is 55 (slightly below water-level)
+		removeCavesBelowY: 55
+
+		# With this value set to true, BlueMap uses the block-light value instead of the sky-light value to "detect caves".
+		# (See: removeCavesBelowY)
+        # Default is false
+        caveDetectionUsesBlockLight: false
 		
 		# With the below values you can limit the map-render.
 		# This can be used to ignore the nethers ceiling or render only a certain part of a world.
@@ -102,9 +117,10 @@ maps: [
 		
 		# We dont want a blue sky in the end
 		skyColor: "#080010"
-		
-		# In the end is no sky-light, so we need to enable this or we won't see anything.
-		renderCaves: true
+
+		# In the end is no sky-light, so we need to set this or we won't see anything.
+		removeCavesBelowY: -10000
+		worldSkyLight: 0
 		
 		# Same here, we don't want a dark map. But not completely lighted, so we see the effect of e.g torches.
 		ambientLight: 0.6
@@ -117,9 +133,10 @@ maps: [
 		world: "world/DIM-1"
 		
 		skyColor: "#290000"
-		
-		renderCaves: true
-		ambientLight: 0.6
+        worldSkyLight: 0
+
+        removeCavesBelowY: -10000
+        ambientLight: 0.6
 		
 		# We slice the whole world at y:90 so every block above 90 will be air.
 		# This way we don't render the nethers ceiling.

implementations/fabric-1.16.2/src/main/resources/de/bluecolored/bluemap/render.conf

@@ -45,16 +45,31 @@ maps: [
 
 		# Defines the ambient light-strength that every block is recieving, regardless of the sunlight/blocklight.
 		# 0 is no ambient light, 1 is fully lighted.
-		# You can change this at any time.
+		# Changing this value requires a re-render of the map.
 		# Default is 0
 		ambientLight: 0
 
-		# If this is false, BlueMap tries to omit all blocks that are not visible from above-ground.
+		# Defines the skylight level that the sky of the world is emitting.
+        # This should always be equivalent to the maximum ingame sky-light for that world!
+        # If this is a normal overworld dimension, set this to 15 (max).
+        # If this is a normal nether or end dimension, set this to 0 (min).
+		# Changing this value requires a re-render of the map.
+        # Default is 15
+		worldSkyLight: 15
+
+		# BlueMap tries to omit all blocks that are below this Y-level and are not visible from above-ground.
 		# More specific: Block-Faces that have a sunlight/skylight value of 0 are removed.
 		# This improves the performance of the map on slower devices by a lot, but might cause some blocks to disappear that should normally be visible.
 		# Changing this value requires a re-render of the map.
-		# Default is false
-		renderCaves: false
+		# Set to a very high value to remove caves everywhere (e.g. 10000)
+		# Set to a very low value to remove nothing and render all caves (e.g. -10000)
+		# Default is 55 (slightly below water-level)
+		removeCavesBelowY: 55
+
+		# With this value set to true, BlueMap uses the block-light value instead of the sky-light value to "detect caves".
+		# (See: removeCavesBelowY)
+        # Default is false
+        caveDetectionUsesBlockLight: false
 		
 		# With the below values you can limit the map-render.
 		# This can be used to ignore the nethers ceiling or render only a certain part of a world.
@@ -102,9 +117,10 @@ maps: [
 		
 		# We dont want a blue sky in the end
 		skyColor: "#080010"
-		
-		# In the end is no sky-light, so we need to enable this or we won't see anything.
-		renderCaves: true
+
+		# In the end is no sky-light, so we need to set this or we won't see anything.
+		removeCavesBelowY: -10000
+		worldSkyLight: 0
 		
 		# Same here, we don't want a dark map. But not completely lighted, so we see the effect of e.g torches.
 		ambientLight: 0.6
@@ -117,9 +133,10 @@ maps: [
 		world: "world/DIM-1"
 		
 		skyColor: "#290000"
-		
-		renderCaves: true
-		ambientLight: 0.6
+        worldSkyLight: 0
+
+        removeCavesBelowY: -10000
+        ambientLight: 0.6
 		
 		# We slice the whole world at y:90 so every block above 90 will be air.
 		# This way we don't render the nethers ceiling.

implementations/fabric-1.17/src/main/resources/de/bluecolored/bluemap/render.conf

@@ -45,16 +45,31 @@ maps: [
 
 		# Defines the ambient light-strength that every block is recieving, regardless of the sunlight/blocklight.
 		# 0 is no ambient light, 1 is fully lighted.
-		# You can change this at any time.
+		# Changing this value requires a re-render of the map.
 		# Default is 0
 		ambientLight: 0
 
-		# If this is false, BlueMap tries to omit all blocks that are not visible from above-ground.
+		# Defines the skylight level that the sky of the world is emitting.
+        # This should always be equivalent to the maximum ingame sky-light for that world!
+        # If this is a normal overworld dimension, set this to 15 (max).
+        # If this is a normal nether or end dimension, set this to 0 (min).
+		# Changing this value requires a re-render of the map.
+        # Default is 15
+		worldSkyLight: 15
+
+		# BlueMap tries to omit all blocks that are below this Y-level and are not visible from above-ground.
 		# More specific: Block-Faces that have a sunlight/skylight value of 0 are removed.
 		# This improves the performance of the map on slower devices by a lot, but might cause some blocks to disappear that should normally be visible.
 		# Changing this value requires a re-render of the map.
-		# Default is false
-		renderCaves: false
+		# Set to a very high value to remove caves everywhere (e.g. 10000)
+		# Set to a very low value to remove nothing and render all caves (e.g. -10000)
+		# Default is 55 (slightly below water-level)
+		removeCavesBelowY: 55
+
+		# With this value set to true, BlueMap uses the block-light value instead of the sky-light value to "detect caves".
+		# (See: removeCavesBelowY)
+        # Default is false
+        caveDetectionUsesBlockLight: false
 		
 		# With the below values you can limit the map-render.
 		# This can be used to ignore the nethers ceiling or render only a certain part of a world.
@@ -102,9 +117,10 @@ maps: [
 		
 		# We dont want a blue sky in the end
 		skyColor: "#080010"
-		
-		# In the end is no sky-light, so we need to enable this or we won't see anything.
-		renderCaves: true
+
+		# In the end is no sky-light, so we need to set this or we won't see anything.
+		removeCavesBelowY: -10000
+		worldSkyLight: 0
 		
 		# Same here, we don't want a dark map. But not completely lighted, so we see the effect of e.g torches.
 		ambientLight: 0.6
@@ -117,9 +133,10 @@ maps: [
 		world: "world/DIM-1"
 		
 		skyColor: "#290000"
-		
-		renderCaves: true
-		ambientLight: 0.6
+        worldSkyLight: 0
+
+        removeCavesBelowY: -10000
+        ambientLight: 0.6
 		
 		# We slice the whole world at y:90 so every block above 90 will be air.
 		# This way we don't render the nethers ceiling.

implementations/forge-1.14.4/src/main/resources/de/bluecolored/bluemap/render.conf

@@ -45,16 +45,31 @@ maps: [
 
 		# Defines the ambient light-strength that every block is recieving, regardless of the sunlight/blocklight.
 		# 0 is no ambient light, 1 is fully lighted.
-		# You can change this at any time.
+		# Changing this value requires a re-render of the map.
 		# Default is 0
 		ambientLight: 0
 
-		# If this is false, BlueMap tries to omit all blocks that are not visible from above-ground.
+		# Defines the skylight level that the sky of the world is emitting.
+        # This should always be equivalent to the maximum ingame sky-light for that world!
+        # If this is a normal overworld dimension, set this to 15 (max).
+        # If this is a normal nether or end dimension, set this to 0 (min).
+		# Changing this value requires a re-render of the map.
+        # Default is 15
+		worldSkyLight: 15
+
+		# BlueMap tries to omit all blocks that are below this Y-level and are not visible from above-ground.
 		# More specific: Block-Faces that have a sunlight/skylight value of 0 are removed.
 		# This improves the performance of the map on slower devices by a lot, but might cause some blocks to disappear that should normally be visible.
 		# Changing this value requires a re-render of the map.
-		# Default is false
-		renderCaves: false
+		# Set to a very high value to remove caves everywhere (e.g. 10000)
+		# Set to a very low value to remove nothing and render all caves (e.g. -10000)
+		# Default is 55 (slightly below water-level)
+		removeCavesBelowY: 55
+
+		# With this value set to true, BlueMap uses the block-light value instead of the sky-light value to "detect caves".
+		# (See: removeCavesBelowY)
+        # Default is false
+        caveDetectionUsesBlockLight: false
 		
 		# With the below values you can limit the map-render.
 		# This can be used to ignore the nethers ceiling or render only a certain part of a world.
@@ -102,9 +117,10 @@ maps: [
 		
 		# We dont want a blue sky in the end
 		skyColor: "#080010"
-		
-		# In the end is no sky-light, so we need to enable this or we won't see anything.
-		renderCaves: true
+
+		# In the end is no sky-light, so we need to set this or we won't see anything.
+		removeCavesBelowY: -10000
+		worldSkyLight: 0
 		
 		# Same here, we don't want a dark map. But not completely lighted, so we see the effect of e.g torches.
 		ambientLight: 0.6
@@ -117,9 +133,10 @@ maps: [
 		world: "world/DIM-1"
 		
 		skyColor: "#290000"
-		
-		renderCaves: true
-		ambientLight: 0.6
+        worldSkyLight: 0
+
+        removeCavesBelowY: -10000
+        ambientLight: 0.6
 		
 		# We slice the whole world at y:90 so every block above 90 will be air.
 		# This way we don't render the nethers ceiling.

implementations/forge-1.15.2/src/main/resources/de/bluecolored/bluemap/render.conf

@@ -45,16 +45,31 @@ maps: [
 
 		# Defines the ambient light-strength that every block is recieving, regardless of the sunlight/blocklight.
 		# 0 is no ambient light, 1 is fully lighted.
-		# You can change this at any time.
+		# Changing this value requires a re-render of the map.
 		# Default is 0
 		ambientLight: 0
 
-		# If this is false, BlueMap tries to omit all blocks that are not visible from above-ground.
+		# Defines the skylight level that the sky of the world is emitting.
+        # This should always be equivalent to the maximum ingame sky-light for that world!
+        # If this is a normal overworld dimension, set this to 15 (max).
+        # If this is a normal nether or end dimension, set this to 0 (min).
+		# Changing this value requires a re-render of the map.
+        # Default is 15
+		worldSkyLight: 15
+
+		# BlueMap tries to omit all blocks that are below this Y-level and are not visible from above-ground.
 		# More specific: Block-Faces that have a sunlight/skylight value of 0 are removed.
 		# This improves the performance of the map on slower devices by a lot, but might cause some blocks to disappear that should normally be visible.
 		# Changing this value requires a re-render of the map.
-		# Default is false
-		renderCaves: false
+		# Set to a very high value to remove caves everywhere (e.g. 10000)
+		# Set to a very low value to remove nothing and render all caves (e.g. -10000)
+		# Default is 55 (slightly below water-level)
+		removeCavesBelowY: 55
+
+		# With this value set to true, BlueMap uses the block-light value instead of the sky-light value to "detect caves".
+		# (See: removeCavesBelowY)
+        # Default is false
+        caveDetectionUsesBlockLight: false
 		
 		# With the below values you can limit the map-render.
 		# This can be used to ignore the nethers ceiling or render only a certain part of a world.
@@ -102,9 +117,10 @@ maps: [
 		
 		# We dont want a blue sky in the end
 		skyColor: "#080010"
-		
-		# In the end is no sky-light, so we need to enable this or we won't see anything.
-		renderCaves: true
+
+		# In the end is no sky-light, so we need to set this or we won't see anything.
+		removeCavesBelowY: -10000
+		worldSkyLight: 0
 		
 		# Same here, we don't want a dark map. But not completely lighted, so we see the effect of e.g torches.
 		ambientLight: 0.6
@@ -117,9 +133,10 @@ maps: [
 		world: "world/DIM-1"
 		
 		skyColor: "#290000"
-		
-		renderCaves: true
-		ambientLight: 0.6
+        worldSkyLight: 0
+
+        removeCavesBelowY: -10000
+        ambientLight: 0.6
 		
 		# We slice the whole world at y:90 so every block above 90 will be air.
 		# This way we don't render the nethers ceiling.

implementations/forge-1.16.2/src/main/resources/de/bluecolored/bluemap/render.conf

@@ -45,16 +45,31 @@ maps: [
 
 		# Defines the ambient light-strength that every block is recieving, regardless of the sunlight/blocklight.
 		# 0 is no ambient light, 1 is fully lighted.
-		# You can change this at any time.
+		# Changing this value requires a re-render of the map.
 		# Default is 0
 		ambientLight: 0
 
-		# If this is false, BlueMap tries to omit all blocks that are not visible from above-ground.
+		# Defines the skylight level that the sky of the world is emitting.
+        # This should always be equivalent to the maximum ingame sky-light for that world!
+        # If this is a normal overworld dimension, set this to 15 (max).
+        # If this is a normal nether or end dimension, set this to 0 (min).
+		# Changing this value requires a re-render of the map.
+        # Default is 15
+		worldSkyLight: 15
+
+		# BlueMap tries to omit all blocks that are below this Y-level and are not visible from above-ground.
 		# More specific: Block-Faces that have a sunlight/skylight value of 0 are removed.
 		# This improves the performance of the map on slower devices by a lot, but might cause some blocks to disappear that should normally be visible.
 		# Changing this value requires a re-render of the map.
-		# Default is false
-		renderCaves: false
+		# Set to a very high value to remove caves everywhere (e.g. 10000)
+		# Set to a very low value to remove nothing and render all caves (e.g. -10000)
+		# Default is 55 (slightly below water-level)
+		removeCavesBelowY: 55
+
+		# With this value set to true, BlueMap uses the block-light value instead of the sky-light value to "detect caves".
+		# (See: removeCavesBelowY)
+        # Default is false
+        caveDetectionUsesBlockLight: false
 		
 		# With the below values you can limit the map-render.
 		# This can be used to ignore the nethers ceiling or render only a certain part of a world.
@@ -102,9 +117,10 @@ maps: [
 		
 		# We dont want a blue sky in the end
 		skyColor: "#080010"
-		
-		# In the end is no sky-light, so we need to enable this or we won't see anything.
-		renderCaves: true
+
+		# In the end is no sky-light, so we need to set this or we won't see anything.
+		removeCavesBelowY: -10000
+		worldSkyLight: 0
 		
 		# Same here, we don't want a dark map. But not completely lighted, so we see the effect of e.g torches.
 		ambientLight: 0.6
@@ -117,9 +133,10 @@ maps: [
 		world: "world/DIM-1"
 		
 		skyColor: "#290000"
-		
-		renderCaves: true
-		ambientLight: 0.6
+        worldSkyLight: 0
+
+        removeCavesBelowY: -10000
+        ambientLight: 0.6
 		
 		# We slice the whole world at y:90 so every block above 90 will be air.
 		# This way we don't render the nethers ceiling.

implementations/spigot/src/main/resources/de/bluecolored/bluemap/render.conf

@@ -45,16 +45,31 @@ maps: [
 
 		# Defines the ambient light-strength that every block is recieving, regardless of the sunlight/blocklight.
 		# 0 is no ambient light, 1 is fully lighted.
-		# You can change this at any time.
+		# Changing this value requires a re-render of the map.
 		# Default is 0
 		ambientLight: 0
 
-		# If this is false, BlueMap tries to omit all blocks that are not visible from above-ground.
+		# Defines the skylight level that the sky of the world is emitting.
+        # This should always be equivalent to the maximum ingame sky-light for that world!
+        # If this is a normal overworld dimension, set this to 15 (max).
+        # If this is a normal nether or end dimension, set this to 0 (min).
+		# Changing this value requires a re-render of the map.
+        # Default is 15
+		worldSkyLight: 15
+
+		# BlueMap tries to omit all blocks that are below this Y-level and are not visible from above-ground.
 		# More specific: Block-Faces that have a sunlight/skylight value of 0 are removed.
 		# This improves the performance of the map on slower devices by a lot, but might cause some blocks to disappear that should normally be visible.
 		# Changing this value requires a re-render of the map.
-		# Default is false
-		renderCaves: false
+		# Set to a very high value to remove caves everywhere (e.g. 10000)
+		# Set to a very low value to remove nothing and render all caves (e.g. -10000)
+		# Default is 55 (slightly below water-level)
+		removeCavesBelowY: 55
+
+		# With this value set to true, BlueMap uses the block-light value instead of the sky-light value to "detect caves".
+		# (See: removeCavesBelowY)
+        # Default is false
+        caveDetectionUsesBlockLight: false
 		
 		# With the below values you can limit the map-render.
 		# This can be used to ignore the nethers ceiling or render only a certain part of a world.
@@ -102,9 +117,10 @@ maps: [
 		
 		# We dont want a blue sky in the end
 		skyColor: "#080010"
-		
-		# In the end is no sky-light, so we need to enable this or we won't see anything.
-		renderCaves: true
+
+		# In the end is no sky-light, so we need to set this or we won't see anything.
+		removeCavesBelowY: -10000
+		worldSkyLight: 0
 		
 		# Same here, we don't want a dark map. But not completely lighted, so we see the effect of e.g torches.
 		ambientLight: 0.6
@@ -117,9 +133,10 @@ maps: [
 		world: "world_nether/DIM-1"
 		
 		skyColor: "#290000"
-		
-		renderCaves: true
-		ambientLight: 0.6
+        worldSkyLight: 0
+
+        removeCavesBelowY: -10000
+        ambientLight: 0.6
 		
 		# We slice the whole world at y:90 so every block above 90 will be air.
 		# This way we don't render the nethers ceiling.

implementations/sponge-8.0.0/src/main/resources/de/bluecolored/bluemap/render.conf

@@ -45,16 +45,31 @@ maps: [
 
 		# Defines the ambient light-strength that every block is recieving, regardless of the sunlight/blocklight.
 		# 0 is no ambient light, 1 is fully lighted.
-		# You can change this at any time.
+		# Changing this value requires a re-render of the map.
 		# Default is 0
 		ambientLight: 0
 
-		# If this is false, BlueMap tries to omit all blocks that are not visible from above-ground.
+		# Defines the skylight level that the sky of the world is emitting.
+        # This should always be equivalent to the maximum ingame sky-light for that world!
+        # If this is a normal overworld dimension, set this to 15 (max).
+        # If this is a normal nether or end dimension, set this to 0 (min).
+		# Changing this value requires a re-render of the map.
+        # Default is 15
+		worldSkyLight: 15
+
+		# BlueMap tries to omit all blocks that are below this Y-level and are not visible from above-ground.
 		# More specific: Block-Faces that have a sunlight/skylight value of 0 are removed.
 		# This improves the performance of the map on slower devices by a lot, but might cause some blocks to disappear that should normally be visible.
 		# Changing this value requires a re-render of the map.
-		# Default is false
-		renderCaves: false
+		# Set to a very high value to remove caves everywhere (e.g. 10000)
+		# Set to a very low value to remove nothing and render all caves (e.g. -10000)
+		# Default is 55 (slightly below water-level)
+		removeCavesBelowY: 55
+
+		# With this value set to true, BlueMap uses the block-light value instead of the sky-light value to "detect caves".
+		# (See: removeCavesBelowY)
+        # Default is false
+        caveDetectionUsesBlockLight: false
 		
 		# With the below values you can limit the map-render.
 		# This can be used to ignore the nethers ceiling or render only a certain part of a world.
@@ -102,9 +117,10 @@ maps: [
 		
 		# We dont want a blue sky in the end
 		skyColor: "#080010"
-		
-		# In the end is no sky-light, so we need to enable this or we won't see anything.
-		renderCaves: true
+
+		# In the end is no sky-light, so we need to set this or we won't see anything.
+		removeCavesBelowY: -10000
+		worldSkyLight: 0
 		
 		# Same here, we don't want a dark map. But not completely lighted, so we see the effect of e.g torches.
 		ambientLight: 0.6
@@ -117,9 +133,10 @@ maps: [
 		world: "world/DIM-1"
 		
 		skyColor: "#290000"
-		
-		renderCaves: true
-		ambientLight: 0.6
+        worldSkyLight: 0
+
+        removeCavesBelowY: -10000
+        ambientLight: 0.6
 		
 		# We slice the whole world at y:90 so every block above 90 will be air.
 		# This way we don't render the nethers ceiling.