Hopper: java.lang.NullPointerException

java.lang.NullPointerException
	at azb.b(SourceFile:421)
	at azb.a(SourceFile:405)
	at ays.a(SourceFile:297)
	at ayz.a(SourceFile:270)

---- Minecraft Crash Report ----
// This doesn't make any sense!

Time: 9/27/13 3:21 PM
Description: Rendering screen

java.lang.NullPointerException
	at azb.b(SourceFile:421)
	at azb.a(SourceFile:405)
	at ays.a(SourceFile:297)
	at ayz.a(SourceFile:270)
	at bfe.b(SourceFile:718)
	at atv.S(SourceFile:686)
	at atv.d(SourceFile:619)
	at net.minecraft.client.main.Main.main(SourceFile:101)


A detailed walkthrough of the error, its code path and all known details is as follows:
---------------------------------------------------------------------------------------

-- Head --
Stacktrace:
	at azb.b(SourceFile:421)
	at azb.a(SourceFile:405)
	at ays.a(SourceFile:297)
	at ayz.a(SourceFile:270)

-- Screen render details --
Details:
	Screen name: ayz
	Mouse location: Scaled: (347, 207). Absolute: (1042, 144)
	Screen size: Scaled: (456, 256). Absolute: (1366, 768). Scale factor of 3
Stacktrace:
	at bfe.b(SourceFile:718)
	at atv.S(SourceFile:686)
	at atv.d(SourceFile:619)
	at net.minecraft.client.main.Main.main(SourceFile:101)

-- System Details --
Details:
	Minecraft Version: 1.6.4
	Operating System: Windows 7 (amd64) version 6.1
	Java Version: 1.6.0_22, Sun Microsystems Inc.
	Java VM Version: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Sun Microsystems Inc.
	Memory: 89141792 bytes (85 MB) / 165281792 bytes (157 MB) up to 954466304 bytes (910 MB)
	JVM Flags: 2 total; -XX:HeapDumpPath=MojangTricksIntelDriversForPerformance_javaw.exe_minecraft.exe.heapdump -Xmx1G
	AABB Pool Size: 0 (0 bytes; 0 MB) allocated, 0 (0 bytes; 0 MB) used
	Suspicious classes: No suspicious classes found.
	IntCache: cache: 0, tcache: 0, allocated: 0, tallocated: 0
	Launched Version: 1.6.4
	LWJGL: 2.9.0
	OpenGL: Intel(R) HD Graphics GL version 2.1.0 - Build 8.15.10.2622, Intel
	Is Modded: Probably not. Jar signature remains and client brand is untouched.
	Type: Client (map_client.txt)
	Resource Pack: Default
	Current Language: English (US)
	Profiler Position: N/A (disabled)
	Vec3 Pool Size: ~~ERROR~~ NullPointerException: null