BibTex Entry:

  author = {Holger Winnem{\"o}ller},
  year = 2002,
  title = {{I}mplementing {N}on-photorealistic {R}endering {E}nhancements with
          {R}eal-{T}ime {P}erformance},
  school = {Rhodes University, South Africa},
  abstract = {We describe quality and performance enhancements, which work in
             real-time, to all well-known Non-photorealistic (NPR) rendering
             styles for use in an interactive context. These include Comic
             rendering, Sketch rendering, Hatching and Painterly rendering,
             but we also attempt and justify a widening of the established
             definition of what is considered NPR. In the individual Chapters,
             we identify typical stylistic elements of the different NPR
             styles. We list problems that need to be solved in order to
             implement the various renderers. Standard solutions available in
             the literature are introduced and in all cases extended and
             optimised. In particular, we extend the lighting model of the
             comic renderer to include a specular component and introduce
             multiple inter-related but independent geometric approximations
             which greatly improve rendering performance. We implement two
             completely different solutions to random perturbation sketching,
             solve temporal coherence issues for coal sketching and find an
             unexpected use for 3D textures to implement hatch-shading.
             Textured brushes of painterly rendering are extended by
             properties such as stroke-direction and texture, motion, paint
             capacity, opacity and emission, making them more flexible and
             versatile. Brushes are also provided with a minimal amount of
             intelligence, so that they can help in maximising screen coverage
             of brushes. We furthermore devise a completely new NPR style,
             which we call super-realistic and show how sample images can be
             tweened in real-time to produce an image-based six
             degree-of-freedom renderer performing at roughly 450 frames per
             second. Performance values for our other renderers all lie
             between 10 and over 400 frames per second on home-PC hardware,
             justifying our real-time claim. A large number of sample
             screen-shots, illustrations and animations demonstrate the visual
             fidelity of our rendered images. In essence, we successfully
             achieve our attempted goals of increasing the creative,
             expressive and communicative potential of individual NPR styles,
             increasing performance of most of them, adding original and
             interesting visual qualities, and exploring new techniques or
             existing ones in novel ways.},
  keywords = {3D Texturing; Brownian Motion; Brush-Stroke Extensions; Comic,
             Cartoon, Coal, Pencil, Chalk, Hatching, Painterly Rendering;
             Control-Vertex Acquisition & Identification; Edge-Fading;
             Importance-Functions; Level-of-Detail Measure; Linear, Bi-Linear,
             Tri-Linear Interpolation; Morphing; Natural Media Simulation;
             Non-Photorealistic Rendering; Perspective-Correction; Phong
             Lighting; Projective Texturing; Realistic Rendering; Real-Time;
             Reference-Image Acquisition; Super-Realistic Rendering; Temporal
             Coherence; Textured Brushes; Tweening; Uncertainty-Functions.}