The intuitive categorization of computer-generated
artwork used in this paper was based on the type of artwork (pen-and-ink
illustration, painterly rendering or
cartoon-style). A more general categorization
would be dependent on the way in which the paintings are produced
(refer to Figure ): At low level,
there are approaches that try to physically simulate the distribution
of pigments over a canvas (physical layer).
The next layer, which I have called the tool layer,
deals with the properties of drawing tools and colors. However, it
does not care about the process of drawing itself. This is the subject
of the next layer, called the painting layer.
The mental layer, which forms the highest
level in this model, looks at the way in which artists think
when painting.
At the highest level (mental layer), we have seen
an approach that deals with the problem of composition (Section
, Cartoon-Style Rendering). In the painting
layer, traditional painting style approaches for pen-and-ink were
presented (see Section
), starting with the Comprehensible
rendering of 3D-Shapes and Computer-Generated Pen-and-Ink Illustrations.
With the use of fast silhouette determination and Tonal
Art Maps, it is now possible to render pen-and-ink-style drawings
in real-time, for example in games. Other types of painting
styles mentioned in this report include the rendering of Chinese
Portrait and Landscape Paintings, Sumi-e (Section
)
and Cartoon-Style Images (Section
).
Additionally, an approach that simulates the artistic learning
of painting style through repetition (Image Analogies, Section
) was presented. For the tool
layer, we have seen a simulation of painting with various brush
strokes and sizes (Section
) as well
as a discussion on the influence of line direction (Section
) for hatched illustrations. Colors are often
simulated in the physical layer, with watercolor (Section
) and graphite pencils
(Section
) being examples. Furthermore, the
mentioned three-dimensional painting techniques (Section
)
can also be seen as physical approaches, because the distribution
of particles on a surface is computed.