Project 2

Hamlet with Tines

This second project will allow you to use motion-tracking to give life to an animated character. In this case you are going to use OpenGL to help a fork play Hamlet. I will supply the audio files, but you need to supply the motion (and emotion) to go with it.

Why a fork? A fork is quite easy to create in OpenGL so you can concentrate on moving the fork to give it appropriate emotion for the scenes. You can give your fork either 3 or 4 tines (the pointy parts) and the rest of the design is up to you as long as it looks like a fork, and as long as you create it completely within OpenGL - no importing models. Note that you can not add any additional 'body parts' to the fork - no extra arms or legs, or eyeballs or ears or hair. You can make the fork move or jump around the set if you want, or it can stand in the same spot. You can twist or bend the body of the fork, and each of the tines. If you have any question about whether your fork design is legitimate then you should check with Andy.

What does the fork get to do? The fork gets to play two scenes from Hamlet - one longer (about a minute) and one shorter (about 30 seconds). The staging of the scene is up to you - Richard Burton's Hamlet was done on a minimal stage in street clothes, so you don't need lot of setting to stage Hamlet. The fork can be alone on a black stage with only minimal props, or you can create a set and some props. Several of these scenes suggest props (knife, skull, etc) and sets (graveyard, etc). If you want any props or backdrops, then you need to create them yourself in OpenGL. You can set up your lighting any way you wish to get the effect you want.

There are several very good renditions of Hamlet that have been preserved on audio and video. Unfortunately the audio quality on both the Sir Lawrence Olivier version and the Richard Burton version is rather lacking by today's standards - and they each took their own liberties with the text, as did Mel Gibson. Fortunately, in 1992 before filming Hamlet, Kenneth Branaugh and friends did a dramatization of the complete play for BBC radio. That is the version of the audio that we will be using.

For the longer speach you have three choices:

For the shorter speach you have three choices:

All of the files are given in aiff format (8K, mono, 16bit) which is compatible with the SGI machines. The simplest way to play these on an SGI is: playaiff soundfile.aiff

In order to get the fork to move, we will use motion capture. The virtual reality equipment in EVL is designed to monitor the location and orientation of the user to update the graphics. Instead we can use this equipment to record the position and orientation of the user and then use those positions and orientations to move the fork. We have three trackers on most of our VR devices, typically one for the head and one for each hand, so you can simultaneously record the position and orientation of three locations.

I am providing a piece of software to record those positions and orientations into a text file. The software is called 'capture' and can be found in ~aej. You start the program by typing 'capture'

To do the motion capture, you stand in the CAVE and start the recording by pressing the left button on the wand and stop the recording by pressing the right button. Each time you press the left button you will create a new text file. Be sure to keep the original recordings - you will need to turn them in. You will probably need to edit the resulting files (e.g. cropping )and you should note what modifications you have made to those files. The files will give the locations in the CAVE's coordinate system where 0,0,0 is at the center of the CAVE on the floor so you will need to adjust the coordinate system in your playback program. The sound file "sound.aiff" starts playing automatically when you press the left button; this allows you to play back the sound and do your acting to the sound file. You may want to try and do the whole speach at once, or do it in segments and then conenct the files together. You may want to act out all the 'body parts' of the fork at once, or do them one at a time. You may end up with one large data file or a bunch of separate ones. There are lots of options for how to do this.

While you are recording you will be able to see a representation of where the computer believes the sensors are so you can adjust your behavious accordingly. You will probably want to 'overact' somewhat and be a a bit more dramatic in your gestures.

You should do the long scene straight - that is you should do it seriously. For the second shorter scene you can either do it seriously or goof on it and parody the speach. Its up to you.

I have set aside October 2nd in the lab for people to use the CAVE to do their recordings. We will set up a schedule and each person will have an hour to do their recordings.

Once you have the recordings done you should be able to do the rest of your work on the SGI O2s that are available in the Computer Science labs on the second floor of SEL.

Now that you have all of the motions recorded you can use them to move the fork in your OpenGL programs (one for the first speach, one for the second speach).When you run either of the programs it should open up a 500 x 500 pixel resizable window showing an appropriate view of the action with the fork on stage. Pressing the 'F' key starts the audio playing and the fork acting. Pressing the left and right arrows allows the viewer to circle around the scene - you should give the user the 'best view' to start with but the user is free to change that view.

The data file that you create gived the time (in seconds) since capture started, then for each sensor it gives the position (3 floats) and orientation (3 floats). Standing in the center of the CAVE looking at the front screen, the position X is left (negative) to right (positive); the position Y is 0 and the floor and positive upward; the position Z is ahead (negative) to behind (positive.) The orientation is in the order pitch, yaw, roll where pitch is down (negative) to up (positive); yaw is right (negative) to left (positive); roll is clockwise (negative) to counterclockwise (positive.)

Before the project deadline you should create a directory containing the C/C++ source code for both programs, the two executables, the motion-capture text files, the final version of the files used by your applications, the notes on what changes you made to the motion capture files to generate the final versions of the files.

Obviously all of the code, aside from that which I provide, should be your own. In order to play the sounds we will use the brain-dead approach of doing a system call from within the program. Its not the best way, but its simple and it seems to work quite well.

Now I would suggest that the first thing you should do is listen to the audio file for the scenes and chose the two that you like. What are the main emotions in that scene? How might you want to stage the scene? If you haven't read the play in a while, or if you haven't read the play at all, then you probably should read it for the context - see the links below. If you want to take the easy way out then you can take a look at how various productions of Hamlet have staged these scenes, but note that these audio files come from a BBC Radio production so there is no accompanying video. I would caution against trying to do a straight translation of Olivier's or Burton's or Branaugh's actions into a fork - I don't think that will work. Start looking at forks - different styles of forks. Check the web. Go to stores that sell silverware sets. Get ideas. Start drawing forks. Start drawing storyboards. See what parts of the fork you are going to need to move, and how they will need to move.

For more information on Hamlet, including the full text(s) of the play, please see

last revision 9/19/01