Talk:Light

Actual Number of Lighting Levels?
I'm not sure if someone was mistaken when they wrote it on here, or if it's simply been changed since Indev, but there are definitely more than just 9 levels of lightness in Alpha. The light from a torch on the floor of a flat, enclosed cavern reaches 13 blocks away from the source, with progressively dimmer light on each block; combined with the max light level (on the source block itself), and the "complete darkness" level on blocks beyond the torch's illumination, that makes 15 different levels of light. And I'm pretty sure that there are more than that in total, since the max level of sunlight looks brighter than the max level of torchlight.

So there are at least 16 different levels of light, including total darkness. I didn't want to change the wiki right away, since I just joined, and because I don't actually know how many levels there are, since I don't know how many are between max torchlight and max sunlight. Plus I don't feel like going to the trouble to make an updated version of the example gif showing how light works. Also I wanted to make sure this wasn't just happening because of something I did in my settings or something, and verify it wasn't only happening on my computer, though I doubt it is. Just wanted to point it out, so that people more familiar with the game/wiki can help figure out what the article should say. - Alazar 19:28, 15 September 2010 (CDT)
 * best guess is any bite size value (a 2^x). water has 8 levels if you count the source/landing tile, 7 if you don't. Soul4hdwn 21:48, 15 September 2010 (CDT)
 * Ahh, probably so, I had forgotten how often the values are byte-based - 64 items in one inventory slot, etc. Well, after testing some it looks like it is most likely 16 levels, and since that fits the byte-sized theme going on, that ought to be it. I'll fix the article, although I still really don't know how to/feel like making a replacement gif. D: Alazar 22:31, 15 September 2010 (CDT)

Fix'd. Codewarrior 22:32, 15 September 2010 (CDT)

Oh, wow, I leave the talk page to work on the article and everything's already been perfectly redone. Awesome! Alazar 22:35, 15 September 2010 (CDT)

What light level is dangerous?
Since I dont want monsters spawning in my fort, and i'd rather not have it entirely covered with torches, what luminescence level do mobs require to spawn? Obviously they can spawn in at least level 4, as they spawn at nighttime, and maybe even a little higher as ive seen them spawn during dusk.

Answered: 7 or less, now on page. Erich666 18:40, 11 February 2011 (UTC)

How do light levels decrease on a diagonal path?
Do light levels decrease in whole block decrements, or is the -1 light level per block a distance calculation where the block is the base unit and the light level is adjusted according to the hypotenuse length. In other words, if a torch is placed on the ground at point (0,0), at point (6,6) is the light level 8 or 5.147? –The preceding unsigned comment was added by (Talk)  Please sign your posts with

It is strictly whole adjacent blocks. If you want to measure distance, it's [Manhattan distance]. The torch would see light level 2, because it is 12 blocks away. —KPReid 21:58, 16 September 2011 (UTC)

How are half-blocks lit?
I'm adding lighting to Minecraft Overviewer (http://github.com/brownan/Minecraft-Overviewer) and I have a pretty firm grasp about how blocks are lit in Alpha, except for the half-block, which seems to borrow its lighting from neighboring blocks in a weird way. Does anyone have the algorithm used down pat, or even any insights? Any info would be appreciated. -- agrif 02:30, 14 October 2010 (UTC)

Monster spawning in Halloween update?
Since the Halloween update, monsters can spawn on higher light levels the deeper it is. Has anyone tested the values relative to depth, and another question: Which square(s) are taken into account? Do monsters need a single floored square with an appropriate light values to spawn? Or do they need a number of squares matching their size, with appropriate light values? -- Ramperkash 10:57, 2 November 2010 (UTC)

Submersible Light Sources
What light sources operate underwater? Maybe this should be mentioned in the table of lights? I'd do it myself but I don't know first-hand. NightChime 08:23, 20 November 2010 (UTC)

Jack O' Lanterns work underwater. I've seen water over lava without obsidian forming (super rare, I think). I'd guess redstone ore (when touched). Anything else? Glowstone, furnaces, portals? Erich666 18:40, 11 February 2011 (UTC)

Lighting oddities.
I had a world where I had a three block wide, ~15 block high column of lava spilling down the wall of my tree farm, as well as a 'fountain' (a lava spring set so it would land on another block and spread out in a fan, about three blocks high). The fountain's lava was bright and gave off the correct light, but the column appeared dark, the tiles themselves being darker than the fountain's, and gave off little or no light. I put torches next to it and they lit the lava up as if it was a dark tile.

On a multiplayer server, a friend built a big room in a lake, with one layer of water over it. He filled the room with torches and saplings in a checkerboard pattern, so every tile that did not have a tree in it had a torch. The room was darker even in direct sunlight than the hallway that led into it that had torches every 8 or 10 spaces.

Does the game change light levels for things depending on the depth they're at? My tree farm was hollowed out of a hill, and my friend's was built up from the leveled bottom of a ~10-12 block deep lake. --StarChaser Tyger 01:15, 23 January 2011 (UTC)

Translucency
New section added: did I miss any blocks that are translucent (let light through)? -- Erich666 18:40, 11 February 2011 (UTC)

New light system
Maybe add something about the new light system?


 * If you are talking about the 1.3 Beta Ambient Occluance (or something like that), the numbers are the same; anyways, there has been images added. -Psispin 13:11, 15 March 2011 (UTC)

Brown mushrooms?
i don't think brown mushrooms should add light, it sounds so weird. D3l1n 01:48, 4 March 2011 (UTC)


 * Whatever you think or not, the fact is that they do, in a way. It is most likely a bug (though it's been awhile since I have read the article). -Psispin 13:10, 15 March 2011 (UTC)
 * The article states that in order to have a slightly "lit" image, they needed a light level of 1. This will only light the square the mushrooms are on, nothing else. Darkid 14:23, 15 March 2011 (UTC)

Mob Spawners
Mob spawners appear to give off light... Anyone know the exact value?Darkid 13:04, 15 March 2011 (UTC)
 * Mob spawners do not give off light. The fire particle effects are bright but do not give off light. --HexZyle 15:00, 12 July 2011 (UTC)

Reformatting
This isn't about the game, just how the page is set up. Notice (And only for people who are logged in) under category "Effects of light" that there are six edit buttons. I've noticed this is because of the way pictures are, but this just seems sloppy. Can someone figure out a way to reformat the page so that the edit buttons are in their correct space, without loosing the pictures? UGoBoom 18:39, 27 March 2011 (UTC)

Table Add-on
In the table on the Light wiki page, maybe some pictures should be added to show how much lighting each object holds. Like a big flat dark area (at night, cave, etc.) and placing down the light source in the middle of the area, screenshot it and add the picture to the table. I mean its good explaining how bright a light source is but maybe showing it too can help explain things a bit easier.

My idea seems a bit dimwitted but I'm just saying it would help explaining the table a bit easier to those "younger players" WiiMaster890 13:00, 29 March 2011 (UTC)


 * That's actually quite a good idea. I'll do it when I have time. Ary31415 12:58, 3 June 2011 (UTC)

Steve Co. Supply Crates emit light :o
I just made a new save to find wolves, but stumbled on to a Steve Co. Supply Crate. Next I went on a hill which gave me a nice view of the surroundings, and what did I see? I saw two Steve Co. Supply Crates sitting a distance away emitting light in the darkness of the night. Kwank3r 01:50, 1 April 2011 (UTC)
 * That is widely known. They have a luminance of 15. It probably will not be added to the table since it is just a gag and will be removed shortly. UGoBoom 01:54, 2 April 2011 (UTC)

Interesting Lighting (Upcoming 1.8)


Note the blue-ish light in the background. Is this part of the lighting update? --HexZyle 11:35, 3 August 2011 (UTC)


 * Yes, Notch said he would make moonlight a slightly bluish color and artificial light more warmly colored. Verhalthur (talk)(contribs) 13:10, 3 August 2011 (UTC)

1.8 Pre-release lighting glitch
http://www.youtube.com/watch?v=yJ00sW3fmQA

Apparently placing a torch in the middle of the ocean confuses Minecraft. RacinFreek 05:23, 10 September 2011 (UTC)
 * It appears that the lighting system doesn't recognize torches being knocked off by liquids. This also happens with fires created by lightning. CertainlyNot 13:57, 29 September 2011 (UTC)

Concerning light_normal.png
Does editing this image change lightness and colors? Cause' I want to do this for my texture-pack. :) --Robotic62 23:01, 16 September 2011 (UTC)
 * It will change the colours, I guess. Editing the light levels wouldn't make sense, since those are, of course, variable. Shellface 23:23, 16 September 2011 (UTC)

Incidentally, how exactly does minecraft pull a light color out of this image? I would guess for night it would use skylight as an x coordinate and blocklight as a y coordinate, but what about during the day? or in-between? This texture seems to replace the powers of 0.8 used by the earlier lighting system so it'd be nice to have some more detailed info. -- agrif 04:47, 25 September 2011 (UTC)

1.8 Bedrock effect?
Should a note be added describing the "water particle effect" that exists near bedrock level and impacts view distance? It seems to taper off at Y 15 or 16 and makes viewing things at a distance in the depths difficult. --68.226.132.85 00:57, 19 September 2011 (UTC)

I added a note about the lower visibility of torches at depth. If someone wanted to expand that with a more-detailed description of the new effect, that'd be great Mbessey 00:57, 24 September 2011 (UTC)

Data Values
According to the source code the values are not what it says in the article but instead the following:

0.0

0.017543858

0.037037037

0.058823526

0.08333333

0.11111113

0.14285712

0.1794872

0.22222225

0.2727273

0.33333334

0.40740743

0.50000006

0.61904764

0.77777773

1.0

Removal of Third Bug
The third bug listed says, "If turned off it will sometimes cause a bug where stairs will turn black. [This has been fixed as of Beta 1.9 Pre-Release 5]." I will remove this becasue if it was fixed more than two versions ago, what is the relevance of keeping this bug note.

New light bugs in 12w08a?
I think there may be a few, because, deep underground and all over, the light level is just randomly 0 instead of what it's supposed to be, it's even more buggy than it normally is.

Spiders becoming neutral
This article says spiders become neutral in light levels of 11 or higher. The Spider page (and what I previously thought) has to have a light level of 9 or higher, not 11. HotdogPi 01:26, 11 March 2012 (UTC)

"rare" glitch of non emitting blocks still emitting light
I have been having the "rare" glitch of having non emitting blocks suddenly emitting light for no reason, although its not rare in my world. I have had three, maybe four cases so far, always close to a structure I made. Two of them were relatively easy to fix: just had to find that block, by looking which blocks are closest to the source and then trial-and-error until you've found it. deleting it will remave te light source.

In the other case however, the situation was more complex. Here's an image: http://i49.tinypic.com/2s9yhj9.jpg As you can see, the entire cave is illuminated. There are no normal lightsources in the cave. Henceforth, finding the glitchy lightsource is impossible (believe me, ive tried. That cave wasnt there naturally - I blew it out with tnt) cuz almost every block is emitting.

Ive tried to map the problem, and in one occasion i was able to find a similar phenomenon, but isolated. It appeared that the problem was related to blocks that gave a lagtime wen you tried to delete them. In this situation, these blocks where orientated around a 1*1 pillar (which was not laggy, for some reason) in some sort of ring. When i removed these blocks untill a certain depth (they seem to go all the way up and down, as long as there are blocks) practically all the light, in the ENTIRE cave went out. It went back on a few minutes later, when i was trying to figure out how the hell I did that.

Protip: if you find laggy, emitting blocks; dont use tnt. my MC froze for over 5 mins. Hope this cound be of any use.

-Zalbaag-


 * I have the same exact issue with my dark hallway in 1.4.6 (It's the first time I see this glitch) : its dimensions are 3*3*128, it contains no light source whatsoever and it's surronded all the way by completely opaque blocks (Oak wooden planks (not slabs) for the floor and the celling (along with some unactive redstone lamps which I'm sure I have updated) and horizontal Oak wood for the walls). However, it's completely bright !
 * I have tried to rebuild the ceiling, it worked for a while but then the glitch reappeared by its own ! I'm really pissed off since this hallway was intended to be dark and scary ...


 * Notes :
 * I've used TNT to destroy a NPC village to make room for the hallway BUT then I changed my mind and made it pass above it without rebuilding.
 * There's another hallway UNDER the first one which doesn't seem to have the problem even through it's closer to the destroyed NPC houses. this one is 3*3*64.
 * These hallways are floating in the air.
 * I'm playing in default superflat in a world generated in 1.4.6.
 * I don't suffer much from lags. (I didn't at all when I built my hallway.)
 * Missingno 26 10:19, 24 December 2012 (UTC)


 * I fixed your spelling, because "omitting" means not doing something they normally would, which is opposite toi your meaning. Also, weird bug -- I suggest submitting it to the Mojira bug tracker. --Mental Mouse 13:22, 24 December 2012 (UTC)

Light from multiple sources is not cumulative
Wanted to light up a nether fortress to avoid Blazes and made a few tests using torches and signs (signs change brightness to match the light level, making comparison easy). A torch (Light level 14) will have a light level of 13 next to it and 12 diagonally. Having two torches one space apart will still net a light level of 13 in that space. Is this interesting enough to put on the page?

12   12    12 13 12 13 12 12 13 14 13 14 13 12    12 13 12 13 12       12    12

(90.227.80.118 22:48, 15 December 2012 (UTC))
 * I put it in. I'm surprised it wasn't there already -- I certainly knew it from experience, and I think it's implied elsewhere on the wiki. --Mental Mouse 12:03, 24 December 2012 (UTC)

Jack'o'Lantern lighting
To me it seems the face of the Jack'o'Lantern and its side all give light level 15, not less for the sides. My test : enclosing myself in a bl 0 room, with a lantern at my eyes level; then standing right next to it, on the side and on the face, checking the bl given by f3. 14 in both cases.

(Preceding was not signed)


 * Correct as of 1.4.7. Mojang was attempting to make various "sided" blocks give different light levels -- a lit furnace, I believe, is 13, so it would have been "almost" the same as "pretend there is light level 12 in the space in front of the furnace".
 * The problem, as I understood it, was that you still wanted the furnace front face itself to be 13 (and note that putting a "12 in front" does not supply a source for that 13), but you did not want the rest of the furnace to look that bright, which meant that a single block would have 4 different lighting values on the different faces. The code worked, but was not optimized fast enough.
 * Keybounce 14:50, 23 March 2013 (UTC)
 * Keybounce 14:50, 23 March 2013 (UTC)

Code walk though / page review needed
This page is in need of a major review.

Examples of something I know is dated/wrong in 1.4.7: Sun lighting level is more than 7 when in thunder. Monsters do spawn, probably as a special case in the spawning code, but I know what 7 looks like, and that is NOT light level 7 outdoors.

Additionally, "What's my light level" agrees with me -- actual reported light level is 12, which matches the visual.

Keybounce 14:52, 23 March 2013 (UTC)