On the 64-Bit Client there is a problem with the shader when it rains in the game and then when you look at the ground you see a lot pixelation. Basically the ground looks like a giant disco ball being hit by a strobe light. There is also another issue with this concerning water and mobs in water you are unable to distinguish the mobs when in watery terrain (i.e. Crocs).
Screenshots:
imgur.com/a/bG7H6
System Specs:
OS X El Capitan Version 10.11.3
iMac 21.5 inch (Mid-2011)
2.7 GHz Intel Core i5
12 GB 1333 MHz DDR3
AMD Radeon HD 6770M 1GB VRAM
Any and all help would be appreciated. Looking for
chris.dillman to post why this is happening.