Frequently Asked Questions
This page contains Frequently asked questions about Shaderpacks.
I cant' even select the shader pack.
If the pack isn't showing up in the shader selection menu or does not appear to do anything in-game, it may have downloaded incorrectly. Some web browsers (like safari) don't handle zip files correctly by default. You can either turn off "open safe files after downloading" (only applies to safari), or use a different browser, like firefox or chrome. Alternatively, you may have assumed it was necessary to manually unzip the file - it is not. On the other hand, some packs might even be zipped incorrectly to begin with. In this case, try extracting the zip file manually. The folder structure for unzipped shaders should be .minecraft/shaderpacks/(shader name here)/shaders/(everything else here). If you don't know where your .minecraft folder is, see this link.
Shaders crash my game.
There are two different types of crashes Minecraft can generate: Java crashes, and native crashes. Both types will generate a crash log file, and this crash log is absolutely essential for diagnosing the issue. Java crashes will put this file at .minecraft/crash-reports/crash-(date)-(time)-(client or server).txt, where as native crashes will put the file at .minecraft/hs_err_pid(number).log instead. If you don't know if your crash was java or native, check for both of them. If you have more than one crash log, and you don't know which one is the correct one, delete all existing crash logs and launch the game again. When it crashes a 2nd time, there will now only be one crash log anywhere. Once you have your crash log open...
For Java crashes: If the crash log says java.lang.NoSuchFieldError: field_191308_b and you're on 1.12.2, update Optifine to the latest version (G5 as of time of writing). If your crash log does NOT mention that specific error, then ask about it in main.
For native crashes: Search for Problematic frame near the top. If the problematic frame mentions atio6axx.dll, then you need to perform a minor LWJGL patch. More info on this can be found in this PDF. If the problematic frame starts with nv or ig, then you probably need to update your Nvidia or Intel graphics drivers respectively. If the problematic frame starts with libGLProgrammability, the shaderpack you're using is not compatible with the M1 chip, and you should see the GPU column on the Shaderpacks page for alternatives.
In both of the above cases, if your error is not covered above, join our Discord server and ask about it in #main. Upload your crash log as well, as we can't do much without it.
Shaders do not crash, but don't look right either.
The first thing to look for when debugging shaders is the dreaded "invalid program" error. If a shader fails to compile, you will see "invalid program" in your chat menu when you enable the shader pack. However, it won't tell you what the actual issue is. For that, you'll need to look in your log file. If you have Forge installed, this can be found in
.minecraft/logs/fml-client-latest.log. Otherwise, use
.minecraft/logs/latest.log instead. Simply upload this log file on our Discord server, and we'll help you figure out what the issue is. It also helps if you do not select any other shader packs after the broken one. This way, the broken one will be the last thing in your log file, so it's easier for us to find information on it.
Note: If your chat says "OpenGL error", you can ignore this. It's not related to invalid programs. If these messages bother you, you can disable them through Video Settings > Other > Show GL Errors: OFF. Hiding GL errors will not hide invalid program errors.
If you don't have any invalid programs, the next thing to check is mods. Try running the shader pack with just OptiFine and nothing else. Not even Forge or Fabric. If it starts working again, then it's probably a mod issue. Luckily, most mods will have config options which allow you to disable problematic mod feature(s) without removing the entire mod. Config files can be found in .minecraft/config. In 1.13+, forge config files are split up into client, server, and common config files, though not every mod will have all 3 of these files. Nevertheless, client should usually be the first config file you open when trying to find a config option that fixes shaders. If the mod does not have a client config file, try the common one next. You will never have to open the server config file to fix shaders.
Common mod problems and fixes
Advanced Rocketry: Set overworldSkyOverride to false.
Astral Sorcery: 1.12.2 and earlier: Add 0 to weakSkyRenders. It should look like this: S:weakSkyRenders <
1.15.2: Add 0 to weakSkyRenders. It should look like this: weakSkyRenders = [ 0 ]
1.16.4: Add "minecraft:overworld" to skyRenderingConstellations. It should look like this: skyRenderingConstellations = [ "minecraft:overworld" ]
Better End: Set "customSky [default: true]" to false in config/betterend/client.json if it causes issues with the shader pack you're using.
Better Foliage (1.12): Won't necessarily crash, but can cause waving foliage to break in some shader packs. To fix this, the config option Mod Options > Better Foliage > Shader Configuration should match the values specified in your shader pack's block.properties file. Note: block.properties can contain IDs for multiple MC versions, so be sure to use the correct IDs for your MC version. If you're not sure what IDs to use, ask the pack's developer.
Betweenlands: Set use_shader to false. Note: This will fix some rendering issues, but the dimension itself might not have working effects from your shader pack.
Botania: Set fancySkybox.enable AND shaders.enabled to false.
COFH Core (1.15+): Set Render Area Effect Block Breaking to false.
Computer Craft Tweaked: Set monitor_renderer to "gui.computercraft:config.peripheral.monitor_renderer.vbo".
Extended Days: Set Override Sky Rendering to false.
Litematica: Set Visuals > enableRendering to false.
Psi: 1.12: Set B:"Use Shaders" to false. 1.15 and later: Set useShaders to false.
Rats: Turn off Fast Render in Video Settings > Performance.
SnowRealMagic: Turn on Old Lighting in Video Settings > Shaders.
The Midnight Mod: Set rift_shaders to false. Note: This will fix some rendering issues, but the dimension itself might not have working effects from your shader pack.
Thermal Dynamics: Add Unifine to your game: https://www.curseforge.com/minecraft/mc-mods/unifine
If you've ruled out all of the above mods, the next step for figuring out the culprit is to do a binary split search: Step 1: Split your mods into 2 groups. Step 2: Test both groups, and keep whichever group is still broken. Step 3: Repeat until there's only one mod (and its dependencies) left. Once you're done, let @Builderb0y know which mod was the problem so he can add it to the above list.
Still broken even in vanilla?
Sometimes, certain video settings options can break shaders as well. The easiest way to check if this is the case or not is to: 1: Make a backup of .minecraft/options.txt, .minecraft/optionsof.txt, and .minecraft/optionsshaders.txt. 2: Go to Options > Video Settings > Other > Reset Video Settings. 3: Re-enable the shader pack. If it starts working again, then you probably changed a setting which the shader pack didn't like.
List of video settings which are known to cause issues
Brightness: Make sure this is set to a reasonable value. If you set this to an extreme value with mods or by manually editing options.txt, don't do that.
Quality > Anisotropic Filtering: This can sometimes break shader packs which use voxellization. Turn this OFF if you have issues with it.
Quality > Emissive Textures: Resource packs which use OptiFine's emissive textures do not play nicely with shader packs which use specular data. Turn this OFF if you have issues with it.
Quality > Connected Textures: This can sometimes break shader packs which use Parallax Occlusion Mapping (or POM for short). Turn this OFF if you have issues with it.
Quality > Natural Textures: This can sometimes break shader packs which use Parallax Occlusion Mapping (or POM for short). Turn this OFF if you have issues with it.
Quality > Custom Sky: Resource packs which use OptiFine's custom skys do not play nicely with most shader packs. Turn this OFF when using such resource packs and shaders at the same time.
Details > Clouds: Vanilla clouds do not always work correctly with shaders, particularly in old versions. Turn this OFF if you have issues with it.
Details > Trees: Set this to Fancy if leaves show terrain through them, xray-style.
Details > Sky: Turn this ON.
Details > Alternate Blocks: This can sometimes break shader packs which use Parallax Occlusion Mapping (or POM for short). Turn this OFF if you have issues with it.
Performance > Fast Render: This can sometimes break shader packs in unpredictable ways. Turn this OFF if you have issues with it.
Shaders > Render Quality: This can sometimes break shader packs in unpredictable ways. It's best to just leave this set to 1x.
Shaders > Shadow Quality: This can sometimes break shader packs in unpredictable ways. It's best to just leave this set to 1x.
Shaders > Old Lighting: This can sometimes make blocks appear brighter or darker than they should be. It's best to just leave this set to Default.
Other miscellaneous things to check
Versions: Sometimes a shader pack will only work in specific versions. At the time of writing this, 1.16.5 is the most stable version for shaders, and 1.17 is known to be buggy. Try using 1.16.5 before reporting bugs.
Iris: At the time of writing this, Iris does not yet support every feature that every shader pack needs to function properly. Try regular OptiFine instead before reporting bugs.
3rd-party clients: Some 3rd-party clients contain their own broken, outdated, or even illegal distributions of OptiFine. Test in the official Mojang launcher before reporting bugs.
Hardware and drivers: Some packs don't support certain GPU manufacturers or drivers. The Shaderpacks page tells you which graphics cards a pack is supposed to be compatible with.
Still not working?
If you have ruled out faulty downloads, invalid programs, mods, graphics settings, and system configuration issues, then the next step is to report the issue to whoever develops the shader pack. Most popular packs have a channel in our Discord server. Remember to state your issue CLEARLY. "It's broken!" doesn't help. Additionally, be sure to provide screenshots or videos of your issue with the F3 menu open. Your F3 menu gives us a lot of useful information that we can use to diagnose the problem. You may also be asked for log files, so be prepared to give those too.
I got a pack to work, but I'm getting really bad framerate while it's enabled.
Pretty graphics don't come out of nowhere. All shader packs will be worse on framerate than having shaders disabled. Sometimes, this is unavoidable, because there's no fast way of doing a certain effect within the limitations of Minecraft's rendering engine or OptiFine's pipeline. The good news however is that some packs have config options to disable certain effects. The config options for shader packs can be accessed by clicking "Shader Options" in the bottom right corner of the shader selection menu. Depending on your OptiFine version, you may or may not also be able to open this menu by pressing F3 and O at the same time. Either way, mess around with this menu a bit, and try disabling or reducing effects that you don't care about. If you're lucky, you might be able to get a combination of effects that you like, at an acceptable framerate.
See also the Performance Tips page for shaderpack-independent tweaks you can make to the game to make it run faster with minimal quality loss.
If all else fails and you just can't get the pack to do what you want, all is not lost! Remember, there's more than one shader pack out there. Try a few until you find one that does work for you.
Sunlight is leaking into totally enclosed caves.
Take a look at Chunkloading.
I like the water from <some pack>, but I like the clouds from <a different pack>. Can I combine the two packs?
Usually, no. There's no "standard" way of doing almost anything in shaders, so different packs usually do effects in different ways. Combining packs is nearly impossible. If you're good at coding though, you can certainly give it a try.