Look into how F7 works
https://cdn.discordapp.com/attachments/234936569360809996/539890558399676436/2019-01-29_11.31.37.png
that's in 4.6. F7 does not show red/yellow lines on the :11 - :15 metas of the greg stone blocks
from what lithorn is saying, 6.6 does show red/yellow lines now
Before it used to not show anything on blocks that didn't allow spawning. This is what its doing now in 2.0.6.6aDEV

Did not show in 2.0.5.1 nor in 2.0.6.2DEV
btw, I can't really emphasize this more than by just saying, this is VERY VERY VERY VERY bad thing to happen. I'm sure ppl don't use these w/o adding some lights but one benefit is you don't have to light up every single area. the amt of mobs you could feasibly get if the light levels are accurate could be really disasterous...
Must fix before next release
ok
NO GT block should have the canSpawnCreatures (Or whatever the flag is) set true.. Who even changed that? B A D
public boolean canCreatureSpawn(EnumCreatureType type, IBlockAccess world, int x, int y, int z) {
return false; //GT Machines are not valid for creature spawns, ever.
}
Its been like that for a while. I though I was miss remembering that they blocked spawns.
For at least 3 years. I suspect it is this way so that mobs can spawn on the normal GT stones like marble/basalt/red and black granites.

Everyone OK with just changing it to false? NO mobs spawn on any GT stones?
why in 6.6 does NEI light overlay show red lines on the blocks and not in 4.6 for example.
seems like more than one problem here.
I can guarantee 100% that light level dictates spawnage and that the variants I have in my base and specified earlier, definately keep mobs from spawning on them currently, in 4.6.
someone in 6.6 should test for sure whether or not mobs can spawn on those blocks, and if not, why is light overlay bugging out now when before it was fine.
Sure its possible to set all gt stones disable spawns of mobs but i want to know why this changed from 62 to 66.
Smells like an NEI problem. Could someone try rolling back to the older NEI version? @mitchej123 Any chance your changes or changes in a newer NEI did something here?
I think the smelted ones only as that was the intention? GT stones in the wild should still spawn mobs. I confirmed spawning on SMOOTH Granite, Smooth RED granite, Smooth Marble, all GT blocks. Not the non smelted ones. Had spiders and creepers spawn in
I'm on 5.1, Nei shows yellow on get stone bricks and concrete but I have never seen a mob spawn on them. Nothing I changed was remotely related to this.
I'm on 4.6 and they don't show yellow/red
see above pics
When set to return false, the blocks properly block spawns. When set to using the original code, it definitely allows spawns.
More testing.
Definitely something screwy going on
public boolean canCreatureSpawn(EnumCreatureType type, IBlockAccess world, int x, int y, int z) {
//return false;
System.out.println(" X " +x + " Y "
+y+ " Z " +z+ " Metadata" + world.getBlockMetadata(x, y, z) + " CanSpawn" + ((world.getBlockMetadata(x, y, z) % 8 < 3) ? " True" : "False") );
return world.getBlockMetadata(x, y, z) % 8 < 3;
}
Bisecting. Confirming first GT 33.04 from 6.2 did not have this issue.
33.04 from 6.2 - Broken
6.2 (with 6.0 modpack) - Works
6.0 ( whole modpack) - Works
5.1 (whole modpack) - Works
Based on above testing, there is something happening outside of Gregtech that causing this issue. Will try updating scripts first.
Scripts work fine. Replacing all mods above Gregtech in name. (A-G). Works. Trying bottom half (G-Z). Breaks. Something in the bottom half of mods is causing the problem.
Going back to 6.0 on Q-Z
Going back to 6.0 on G-M
Removing optifine
Optifine is the culprit. Confirming with latest dev pack.
Confirmed.
Looking through google, it looks like OF has caused issues with mobs NOT spawning before. I will take some screenshots and post to the OF github about this problem.
more reasons why not to use, bundle or recommend OF.
optifine is only in zeta pack far testings. Should i remove it ? @richardhendricks
Can confirm, NEI no longer shows spawnable on GT Smooth with Optifine removed. Not seen a spawn since
Optifine should NOT be in the main pack/download. If someone wants it, they should add it themselves.
it will not be in the official pack because its not allowed. Zeta Pack is a private pack for testings @MineAnPlay
Is it possible to run client-side only? I think we can update the pinned instructions with info on the limitations and bug, but not include it by default.
Most helpful comment
Sure its possible to set all gt stones disable spawns of mobs but i want to know why this changed from 62 to 66.