This Minecraft mod “Light Level Overlay Mod” envisages the light levels emitted by torches, glowstone and alike directly on top of blocks, this is helpful to quickly identify areas where mobs can spawn. It shows the light level of the airblock above the block the number is drawn onto, this is the block that is considered for mob spawning, light level 7 or below allows mobs to spawn.

Press F9 (customizable) to toggle the overlay.

Press F9 (customizable) and R to reload the configuration file.

Customization:

After you played with lloverlay the first time a ~/.minecraft/lloverlay.properties file is created with all default configuration options, feel free to modify any of those, you can press F9+R in minecraft to reload the config ingame:

• hotkey: keycode that toggles the overlay
• debug: activates debug messages
• drawDistance: distance in blocks in each direction the overlays are drawn, decrease if you run into performance problems
• textureRow: the textures provided (lightlevel.png) can include multiple “styles” or themes, here you can select which row should be drawn (0 = first row, 1 = second row, …). Each block texture is 16×16 pixel.
• generateInterval: the interval in milliseconds (250 = 1/4 second) in which the lightlevel data are gathered (if you place a torch it’s at least 250 ms till the overlays are updated), increase if you run into performance problems
• showLightlevelUpto: you can set the level up-to the overlay should be drawn.
• drawNonSpawnable: if set to true draw the lightlevel on halfslabs/farmland/glass where mobs can’t spawn.
• useSkyLightlevel: set to true for light levels effected by daylight (all surface blocks 15 light level, unfortunately currently also at night times)

Installation:

Forge

• Download and install Minecraft Forge. Both forge-universal and optifine need to be extracted in the minecraft.jar file. (make sure to install optifine last and to replace all files)
• Copy the lloverlay_*-forge.zip file to your ~/.minecraft/mods/ or %appdata%/.minecraft/mods directory.

Vanilla

Vanilla means an unmodified minecraft version (unmodified bav.class file, that is). This does not work with optifine for instance, because it also modifies the bav.class file. It works the same like any other mod, replace the contents of your minecraft.jar file with the contents of lloverlay_*-vanilla.zip and remove the META-INF directory:

• Locate your minecraft.jar in ~/.minecraft/bin/minecraft.jar or %appdata%/.minecraft/bin
• Unpack the contents of minecraft.jar someplace
• Remove the META-INF folder from the extracted files
• Unpack the lloverlay_*.zip file within, override anything
• Pack the folder again in a zip file named minecraft.jar
• Replace the minecraft.jar with it (backup the original minecraft.jar first)

For 1.5.2

Forge: Download from here

Vanilla: Download from here

For 1.5.1

Forge: Download from here

Vanilla: Download from here

For 1.4.7

Forge: Download from here

Vanilla: Download from here