HolliDance

for SGI




What is it?
Holli Dance is a real time animation program that I intended to look like an MTV video. It depicts a virtual girl who dances. Two virtual camera operators capture the action while a virtual lighting effects person sets the mood. She dances to music played through your workstation's microphone, line in jacks, or CD player (you may need to run a cable from your CD player to your line jacks).

Concept
I originally started this project as a 90 second prerendered dance video, but when I discovered that I could render complex scenes on my Mac in real time, I decided that it would be better to create it has a free-running animation program. This way, I can take advantage of faster computers which can render larger and more realistic scenes without having to rerender the whole sequence every time. The program should also maintain interest longer as no two of its frames look the same.

Requirements
The IRIX version is designed to run on SGI work stations that support Open GL. Frame rates vary from 3 to 5 frames/sec on the O2 to over 25 frames/sec on the Indigo 2 Maximum impact. It should be even faster on Onyx 2's. Holli Dance also runs on Power Macintosh, Be OS computers and Sony Play Stations (Net Yaroze).

Installation
Everything HolliDance needs is contained in the HolliDance directory. HolliDance is designed for use with IRIX 6.x and is compiled to the mips3 format. There is a version that will work with IRIX 5.x called HolliDance5.3. This version does not support audio synchronization, but Holli will dance in silence.

Holli prefers 24 bit, double buffered graphics so she'll look her best. She can, however, make due with at least 12 bit, double buffered graphics.

O2 users should use xscreen to configure their frame buffer for double buffering such as '32+32'.

User options
One of the cameras may be controlled manually and various rendering options are available.

The IRIX version of Holli Dance supports a keyboard interface.

L: Toggle Lights
B: Toggle Background
P: Toggle Pause
C: Toggle Camera
LEFT: Camera Left
RIGHT: Camera Right
UP: Camera Up
DOWN: Camera Down
I: Camera In
O: Camera Out
W: Camera Wide
N: Camera Narrow
D: Toggle Dance When Silent
T: Toggle Texture Display
Q: Quit

The two cameras normally operate automatically, but one may be controlled manually. Tap the 'C' key and then tap the appropriate keys to 'dolly' in and out, zoom in and out, pan left and right, and pan up and down.

The club may be replaced with a simple background, but this will not significantly increase rendering speed.

Three spot lights (one stationary and two moving) normally illuminate the scene, but switching to simple lighting increases rendering speed over 50%.

You can pause the dance and Holli will try very hard to stand still.

Select an audio source and play some dance tunes! Choose songs with good consistent beats and Holli will really groove. She will also sway to slower tunes. Use the SGI audiopanel program to set the audio levels in the yellow region for best results.

Holli can dance in silence if you don't have any music for her or would rather just watch.

Some SGI workstations do not have hardware texture acceleration. Turning off texture display may significantly improve rendering speed.

Safety
Holli Dance simulates nightclub lighting and can display a strobe light effect. Unfortunately, some people can be harmed by strobing light, so as a safety feature, I have included a file in the HolliDance directory called 'NoStrobe'. As long as this file is present, the light strobe effect is disabled. To enable the light strobe effect, simply remove or rename the file. Light strobing can be disabled again by creating any file with the name 'NoStrobe' (file size, type, and contents are not important). I apologize for this complication, but some folks can really be injured with strobing lights and it's best not to take chances!

Technical details
Holli is comprised of over 9,100 polygons. Her club is made up of another 1,500 polygons. Holli is fully articulated with 58 segments. Even her fingers are fully flexible. These models were originally modeled on Animation Master (version 3) as roughly 2,300 and 380 curved surface patches respectively.

Future plans
1. Holli Dance supports a full compliment of X-windows user interfaces.
2. Holli dances around her stage rather than dancing in place.
3. Display Holli as a continuous flexible surface rather than rigid segments.
4. Holli varies her expressions and blinks her eyes.
5. Holli Dance displays stereo images via electronic shutter goggles.
6. Holli Dance works with virtual reality head sets.

Contact
I can be reached via my Web page at www.znet.com/~dwhite. You can email me at dwhite2@san.rr.com.