Skeletal Draw A Skeletal Stroke Based Drawing System

Skeletal Draw is an implementation of our vision of a professional drawing system (Figure 21). The current system is implemented on a 486 PC under MS-Windows , and is derived from a previous Unix version on X. The system consists of less than 15000 lines of C++ code. Basic drawing tools like the free-hand brush, the polygonal pen, rubber rectangles and so on are all available their uses are basically identical to those in most other drawing systems. The major difference is that the strokes are...

Anchoring the Flesh

Zeroth order anchoring is the more often used anchoring mode. It preserves the aspect ratio of a chosen part of a picture so that after application that part would not stretch or shrink with the length of the application path. To perform a zeroth order anchoring is easy. In the stroke definition box, one just needs to use the Anchor Tool to circle the part of the flesh to be anchored and to specify an anchor origin, the position (within the box) to where that part of the flesh is to be...

Review on Skeletal Stroke Deformation

The skeletal stroke deformation has been discussed in detail in 28 , here we will only briefly go through the main points but leave out the mathematical details and derivations. The skeletal stroke deformation is based on localized parametric coordinate system transformation along the stroke application path. A skeletal stroke is defined by specifying a reference backbone and a reference thickness on any arbitrary picture. The purpose of defining the reference backbone and thickness is for...

Speed Lines for Motion Blurring

In both comics and animation, fast action is often represented by speed lines, which suggest the distance an object or character has travelled across the camera before its shutter is closed again. Motion blurring is particularly important in animation because it reduces temporal aliasing effects. Its method of generation in vector based cartoon has not been, however, a well addressed problem. One possible way is to employ temporal antialiasing techniques like stochastic sampling across the time...

Rendering a Recursive Stroke

Rendering a recursive stroke explicitly by determining the resultant geometry is in general impossible. Since a recursive stroke is equivalent to an IFS (Iterated Function System) code (with a condensation set if objects other than itself are present in the definition) 3,4,5,6 , the attractor is often a fractal with a fractal dimension less than 2. We therefore have to resort to one of the approximation methods for rendering these fractals. The Escape Time Algorithm 4 would result in a clean...

General Drawing Applications

We anticipate that skeletal strokes would have considerable impact on many drawing applications in fashion design where stylish bold strokes are often used in interior design where pseudo-3D strokes representing furniture and architectural objects can be laid out with ease in dynamic clip-arts which can deform dramatically beyond the limits of stretching, shrinking, shearing, twisting and bending. If implemented in windowing system kernels or page description languages like PostScript, the...

Animation with Skeletal Draw

Animation takes full advantage of the picture and deformation abstraction capability provided by skeletal strokes. The Skeletal Draw program has also been built with facilities to generate animation sequences. Traditional key-frame technique is used by Skeletal Draw. To create the key-frames, the user directly manipulates the characters in the scene. The system then calculates the in-betweens by interpolating Catmull-Rom splines. After the keyframes have been laid out, the program can do a...