Worksheet Three

This worksheet came a couple of weeks after worksheet two. It was aimed at a slight draft/mock of the final proposal. At this point I was starting to really focus in on my research question and find very useful papers on the subject area.

Introduction

The aim of the project is to find out, through research, if voxels are a viable method of rendering using today’s hardware. Also what practical applications they can have in real time applications,

Motivation


The tremendous evolution of programmable graphics hardware has made high-quality real-time volume graphics a reality (Engel et al 2004). This quote from a paper published in 2004 is entirely correct in what it says yet there has been little in the way of volume rendering appearing in real-time applications such as games. In addition to the traditional application of rendering volume data in scientific visualization,
The interest in applying these techniques for real-time rendering of atmospheric phenomena and participating media such as fire, smoke, and
Clouds are growing rapidly (Engel et al 2004). Although the interest may have been there a few years ago there, again, has been little to show for this interest. The only exception is that there are certain volume rendering methods used within the Direct X 10 framework, but only in the above instances of what would have previously been particle systems. Volume rendering is used mainly for scientific and medical imaging as it gives a representation of the inside of an object, a requirement in medical imaging. The main reason for this is the speed of graphical hardware, medical images did not need to be updated at least 30 times a second required to give the fluid motion required for games. Also the size of the data sets needed for volumetric data were just too large for the standard memory of the home PC user until recently. With the now midrange graphics cards like the ATI 4870 series coming in with memory bandwidths of 107 G bytes/s( need a reference for this as I got it from the box my graphics card came in) and over 1 teraflop of processing power this should no longer be a problem. With 3D graphics becoming set to move away from traditional rasterisation and into a ray traced method there are big things on the horizon for the future of games. In an interview John Carmack says “I have my own personal hobby horse in this race ....... It involves ray tracing into a sparse voxel octree.” This is when the subject really justifies grabbing a lot of attention once again. John Carmack has always been one of the so called gurus of Graphics technologies and his opinions carry a lot of weight in the games community.


Research Question

Using a voxel based approach to creating deformable and destructible objects what are the advantages over using traditional methods?




Addressing the Question

To address the question investigations into the data structures and different methods of rendering volumetric data are required. This is going to be done using papers that were generated by the SIGGRAPH conventions for use in courses at their annual conventions. This will provide a basic foundation for building on what needs to be done in creating the deformable and destroyable objects. This will most likely involve using a physics simulator tool like PhysX. This simulation can then also be used on the traditional types of models to see what kinds of results are obtained. It is more than likely that the volumetric data version will need to be highly optimised as current dedicated graphics hardware is not built for this, but to circumvent this the SDK available from ATI that allows calculations on the graphics card will be used if needed.
The information obtained through this experimental work will allow a table to be drawn up comparing performance of the two methods. This will then allow for a reasonable conclusion to be drawn from the experimental work and hence a full answer to be given to the research question.

Resource Requirements

All that will be required for the project will be a computer with visual studio and a good graphics card, which are available. A few other tools such as ATI's stream SDK or possibly Nvidia's CUDA may also be needed but these are freely available from the appropriate websites for download. An application will need to be made to PhysX makers Ageia for this use of their tool but no problems with this can be foreseen as it is made freely available to students.


References and Bibliography

Engel, K. et al 2004 Real-Time Volume Graphics SIGGRAPH


Eisemann E , Decoret X 2008 , Single-Pass GPU Solid Voxelisation for Real-Time Applications GraphicsInterface

Shrout R 2008 PC Perspective – John Carmack on id Tech6, Ray Tracing , Consoles, Physics and more [Online] Available at: http://www.pcper.com/article.php?aid=532 [ accessed 4th November 2008]