Creating Non-Photorealistic Images the Designer's Way

In NPAR 2002:

Nick Halper and Stefan Schlechtweg and Thomas Strothotte



We present a novel way for quickly and easily designing non-photorealistic images based on elementary operations which are linked together to create a variety of visual effects. Rather than mimicking a visual effect that an artist has already produced, we instead mimick the process undergone for the artist to produce that image. Compared to traditional approaches, this opens the possibility to have the images created by users with no programming skills. We describe a modular system that makes these elementary operations available to the user. A specially designed user interface allows for an easy and intuitive combination of these operations to create an image. Visual feedback is provided to the user at any time and for any stage in the process.


Nick Halper, Stefan Schlechtweg, and Thomas Strothotte. Creating Non-Photorealistic Images the Designer's Way. In Stephen N. Spencer, editor, Proceedings NPAR 2002: Symposium on Non-Photorealistic Animation and Rendering (June 3-5, 2002, Annecy, France), pages 97-104, New York, USA, 2002. ACM SIGGRAPH. (PDF)


Screenshot of the Interface

  • Novel Interaction Method

Comparison of two interaction sequences: (left) interface maps user intention onto the underlying system order of application of effects, and (right) user must be aware of application order of 2D and 3D effects. Notice that on the left, we see a linear progression of effects, whereas on the right, the user has to backtrack to apply effects at appropriate insertion points.

[qt video 38mb with voice]

  • Playing with ideas

This video shows a relatively long sequence (~6min) about how the user can play with ideas. Starting from the two images shown at the left, after playing with the system for a while (sequence in the middle) the user comes up with a 'sponge-painting' effect shown on the right. There were about 10 simple modifiers used to create this image. Notice, that at every point in the sequence the user has simply taken an image and applied a new effect directly to that image. In this respect, even though the screenshot of this sequence looks complicated and disorganised, it is simple to just take any image in the sequence and continue experimenting with it.

[qt video 44mb



© 2002 Nick Halper  [ ]