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<TITLE>Tao User Manual -- <B>Tao</B>'s Cellular Material</TITLE>
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<H2><B>Tao</B>'s Cellular Material</H2>
<P><B>Tao</B> is based around the notion of building complex vibrating structures
from simpler acoustic building blocks. In order to realise this goal
a general purpose adaptable acoustic material is provided. The material
consists of point masses arranged in a regular grid pattern and connected
together with springs. The overall structure of the material is shown in
figure <A HREF="#1">*</A>.
<P><P> <A NAME="1">
<BLOCKQUOTE><CENTER>
<IMG SRC="cells.gif">
</CENTER></BLOCKQUOTE>
<CENTER>A small portion of <B>Tao</B>'s cellular acoustic material</CENTER>
</A>
<P><P>Each point mass or <EM>cell</EM><A NAME="2"> maintains</A> a set of state variables for
its position, velocity, mass, etc., and the overall state is updated in
discrete time steps or <EM>ticks</EM><A NAME="3"> according</A> to rules which take into
account a cell's own state and the states of its immediate neighbours.
More specifically a cell's spring connections to its neighbours exert
forces on the cell and from these forces Newton's laws of motion can
be used to calculate the acceleration and velocity of the cell.
<P>Note that the cells are constrained to have one degree of freedom (in the
direction of the <I>z</I> axis). This has two practical advantages:
<P><UL><LI>It makes the calculations involved in animating the material simpler.
<LI>It also makes it a simple matter to generate time varying waveforms
from the vibrations in the material since all cells will vibrate about a
fixed zero reference point at <I>z=0</I> so long as at least one cell
is fixed at that position.
</UL>
<P>One question which has often been asked in relation to <B>Tao</B>'s cellular
material is: `have you experimented with 3D blocks of material?'. The answer
to this question is no, for the following reasons. Firstly, the computational
expense of such instruments would be prohibitive, and secondly, although the
restriction of working with 2D instruments may at first seem like a limitation,
in practice it doesn't significantly affect <B>Tao</B>'s ability to produce an
wide variety of interesting sounds.
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<LI><A HREF="UserManual_21.html">Cell Attributes</A>
<LI><A HREF="UserManual_22.html">The Emergent Behaviour of the Material</A>
<LI><A HREF="UserManual_23.html">Generating Sound Output from the Material</A>
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<tr><td colspan="3" class="addr"><!-- bottom panel --><ADDRESS><FONT SIZE=-1>©1999,2000 Mark Pearson
<A HREF="mailto:m.pearson@ukonline.co.uk">m.pearson@ukonline.co.uk</A> April 30, 2000</ADDRESS><BR></td></tr><!-- end bottom panel --></table></BODY></HTML>
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