normal mat3 from mat4 extraction util
normal mat3 from mat4 extraction util

stardazed/stardazed-tx,zenmumbler/stardazed-tx,zenmumbler/libzm,zenmumbler/libzm,zenmumbler/stardazed-tx,zenmumbler/libzm,stardazed/stardazed-tx,zenmumbler/stardazed-tx,zenmumbler/stardazed-tx,zenmumbler/libzm,stardazed/stardazed,stardazed/stardazed-tx,stardazed/stardazed