A large non-patterned noise texture occupies a relatively small physical
memory space. Each of a small set of physical pages in physical memory
includes noise texels forming part of a noise texture. A large "virtual"
noise texture is created by mapping each one of a large number of pages
in virtual address space to one of the small set of physical pages;
multiple virtual pages may be mapped to the same physical page. The
physical page that each virtual page maps to is randomly or
pseudo-randomly selected such that the resulting noise texture appears to
be non-repeating. When a noise texel is requested by reference to a
virtual address during rendering, the virtual address of the virtual page
is translated to the corresponding physical address, and the noise texel
is retrieved.