Multimedia in DrScheme

[Mark Guzdial <guzdial@cc.gatech.edu>]

Hi!  I'm a first time caller to the list, and a newcomer to DrScheme. 
We're using DrScheme in our introduction to computing class at 
Georgia Tech.

I'd like to invent some multimedia activities in DrScheme, and to do 
so, I need some existing toolbox functions available at just one 
level lower of abstract, it seems to me.  Or maybe what I want to do 
is already available, or easily implemented, but I just am not seeing 
it.

- I want students to be able to do simple "transition" animations 
between images, e.g., blurs, fades, or even morphing.  There is a 
function for loading a pixmap from a file, and there's another for 
setting a pixel in a viewport.  But what I really need are the 
lower-level functions: To be able to manipulate a pixmap in memory, 
and get individual pixel color values.

- I want students to be able to fill a sound buffer with computed 
values (e.g., a sine wave, and later, a sine wave modified by an 
envelope) and then play the sound buffer.  There is a function for 
playing a sound from a file, but I need to be able to access the 
sound buffer before it starts to play.

These are interesting because they're computationally not very 
complicated, but the results are fun and fairly different from 
traditional CS1 projects.

These basic abilities are available in other languages in 
cross-platform versions, so the basic source code should be 
available.  Squeak (http://www.squeak.org) can do this.  Java can do 
some of this.  CSound can do the sound example cross-platform. 
Tcl/Tk, I believe, can do the transitions programming cross-platform.

Can anyone tell me if
(a) these functions are already available, and how I get to them? or
(b) how to extend DrScheme to allow these facilities?

Thank you!
  Mark
--------------------------
Mark Guzdial : Georgia Tech : College of Computing : Atlanta, GA 30332-0280
Associate Professor - Learning Sciences & Technologies.
Collaborative Software Lab - http://coweb.cc.gatech.edu/csl/
(404) 894-5618 : Fax (404) 894-0673 : guzdial@cc.gatech.edu
http://www.cc.gatech.edu/gvu/people/Faculty/Mark.Guzdial.html