John R. Rankin

Recursive bisection line algorithm

Abstract This article presents a new algorithm for drawing lines on raster graphics devices. The algorithm is not related to Euclids algorithm but instead is based on a fractal definition for the line. The fractal has the same dimension as the topological dimension of the line. The recursive nature of the algorithm results in fewer decisions being made in comparison with other algorithms. Therefore, this line algorithm performs faster especially with lines near to horizontal, diagonal, or vertical. The algorithm does not produce a palindrome and on low resolution devices may not appear to be perfectly straight. It is shown, however, that the line accuracy improves in proportion to the display resolution.

FPS Extensions Modelling ESGs

In this paper we show that the FPS paradigm has metaphorical correspondences with a low level category of ESGs. Extensions of the FPS paradigm lead to simple concept learning lessons analogous to the needs of teachers for the development of low level ESGs for use in classroom teaching. The main FPS extension discussed in this paper is the FSM module. The teacher is not required to recompile any code but simply to provide the data representing the FSM corresponding to each concept learning lesson in the target ESG. The purpose of this research is not to develop the full ESG but rather to show that the FSM module coupled with other extensions to the FPS game development tools provides a means for building future ESG development tools.

Testing metaphorical educational FPS games

It is widely recognized that there is value in making use of modern Games Technology in Serious Games for educational purposes in the classroom and yet tools that enable teachers to construct such Educational Serious Games (ESGs) with minimal programming, artistic, or GT skills are not yet widely available. In this paper we investigate the feasibility of employing the FPS game genre for teaching purposes in the classroom. This is done by starting with a typical FPS game and constructing metaphorical correspondences with the desired ESG category. This mapping highlights the mentality level of FPS games and what it would take to modify them towards the level for real knowledge acquisition as in ESGs. By changing the game world rules to correspond with a classroom study area, we create a metaphorical educational FPS game. In this paper we describe two metaphorical educational FPS games and report on preliminary testing of their use in education. If testing of thesemetaphorical educational FPS games indicates that they would be beneficial in school classes then we intend to pursue the design of software tools and tutorials to enable teachers to develop their own metaphorical educational FPS games in two months or less.

A simple naturalistic hair model

We propose a new computer graphics model to render naturalistic human hair. In this model, a simplified progressive polyline simulation was used for fast processing. The problems of inter-hair collisions and hair-head collisions were avoided by certain assumptions, and the bend in the hair was provided by angle-dependent pseudo-force equations. Several hair-colour and shadowing techniques were tested. Despite the simplicity of the hair model itself, when it was combined with the coloring and shadowing techniques described here, the proposed model did effectively render hair, as illustrated by the still images.

Skinning Analysis of a Mapping Algorithm in Higher Dimensions

Recently, a geometric approach to the coordinatization of measured spaces (called the Map Maker algorithm) was extended to three and high dimensions. This has significance in now allowing a new sort of data projection from higher dimensions to any lower dimension of choice. The algorithms however need a thorough testing review, and this paper makes the necessary thorough analysis of the error and speed performance of the extended approaches. By means of the skinning operation introduced in this paper, we have been able to derive meaningful performance charts with the statistical fluctuations effectively removed. This has resulted in some new findings. We have found that the fit of the data to a given dimensionality is very sensitive to the precision in the given data. In addition, we have resolved a conjecture regarding the dimensionality of the Map Maker algorithm resonating with the dimensionality of the data from which the distance matrix information was derived.

Performance of a Parallel Multi-Agent Simulation using Graphics Hardware

Large-scale Agent-Based Modelling and Simulation (ABMS) is a field of research that is becoming increasingly popular as researchers work to construct simulations at a higher level of complexity and realism than previously done. These systems can not only be difficult and time consuming to implement, but can also be constrained in their scope due to issues arising from a shortage of available processing power. This work simultaneously presents solutions to these two problems by demonstrating a model for ABMS that allows a developer to design their own simulation, which is then automatically converted into code capable of running on a mainstream Graphical Processing Unit (GPU). By harnessing the extra processing power afforded by the GPU this paper creates simulations that are capable of running in real-time with more autonomous agents than allowed by systems using traditional x86 processors. Performance of a Parallel Multi-Agent Simulation using Graphics Hardware

Harmonic Curve Design

Abstract Many aesthetically appealing curves can be generated by using epicycloid and spirographic parametric curve equations. The difficulty in obtaining an interesting and appealing curve comes from having to choose good values for the coefficients in these equations. If a poor choice of coefficients is made the curve generated will have little regularity and a high amount of confusion. Since these curve types involve up to ten real coefficients the set of aesthetic curves is a set of measure zero on the infinite coefficient space. Rather than making random searches through coefficient space another approach which proved to be far more productive in discovering curves of aesthetic appeal was investigated. In this approach we looked at the Fourier Transform of the curves and performed editing on the coefficients in Fourier space. This approach is especially suited to the epicycloid and spirographic curve types which turn out to be simply low-order harmonic functions after suitable filtering and a rotation. As a result, curves can now be defined by free-form input and then cleaned up by this method to yield the nearest epicycle or spirograph.