An isosurface is a discrete representation of geometry. The world is divided
into blocks, and each block contains the distance to the nearest surface.
Inside objects, the numbers are negative; on the outside, they are positive
(this is an arbitrary decision), and the actual surface is exactly the contour
where the numbers are equal to zero.
Texture synthesis describes the generation of repeating images, so-called
textures, from a set of sample images. The algorithms used can, for example,
recognize the pattern of flowers in a flower bed and then create images of
other flower beds that look similar but are not exactly the same.