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<p>Nobody has reached out to me about needing assistance in class
tomorrow. Since it was going to be a "workday", I am officially
cancelling class tomorrow. You can still come use the lab if you
would like.</p>
<p>Now -- some gifts come in small packages... and since we are are
not having class tomorrow, and since I have not seen any houses
"moving", I wanted to give you a snippet of code (a small package)
that is found in my own 3D house code. I have replaced my
"pipeline code", which built the translation and rotation matrices
and applied them to the coordinates, with the following OpenGL
transformations.<br>
</p>
<p><font face="monospace">void pipeline(void)<br>
{<br>
spinX(); spinY(); spinZ(); <br>
glRotatef(SPIN_ANGLE_X,1.0,0.0,0.0);<br>
glRotatef(SPIN_ANGLE_Y,0.0,1.0,0.0);<br>
glRotatef(SPIN_ANGLE_Z,0.0,0.0,1.0);<br>
glutPostRedisplay();<br>
}</font><br>
<br>
where the SPIN_ANGLE_X,Y,Z global variables are modified by their
representative functions...</p>
<pre class="code highlight" lang="c"><span id="LC350" data-testid="content" class="line" lang="c"><span class="hljs-type">void</span><span class=""> </span><span class="hljs-title.function">spinX</span><span class="hljs-params"><span class="hljs-params">(</span><span class="hljs-type">void</span><span class="hljs-params">)</span></span></span>
<span id="LC351" data-testid="content" class="line" lang="c"><span class="">{</span></span>
<span id="LC352" data-testid="content" class="line" lang="c"><span class=""> SPIN_ANGLE_X </span><span class="">= SPIN_ANGLE_X + DELTA_SPIN_X;</span><span class=""></span></span>
<span id="LC353" data-testid="content" class="line" lang="c"><span class=""> </span><span class="hljs-keyword">if</span><span class=""> </span><span class="">(SPIN_ANGLE_X > </span><span class="hljs-number">360.0</span><span class="">)</span><span class=""> SPIN_ANGLE_X </span><span class="">= SPIN_ANGLE_X - </span><span class="hljs-number">360.0</span><span class="">;</span><span class=""></span></span>
<span id="LC354" data-testid="content" class="line" lang="c"><span class="">}</span></span>
</pre>
<p>and the DELTA_SPIN_X,Y,Z global variables are set in the mouse
function.<br>
</p>
<p>You are welcome to use this coding paradigm in your own code.
Remember to call glutPostRedisplay after you change the state of
your graphics window ( you will also need to make sure that you
have double buffering set up correctly).</p>
<p>I hope this helps you - and please let me know if you have
questions. I may not have internet access on Wednesday - but if I
do I will be answering questions. <br>
</p>
<p><br>
</p>
<div class="moz-signature">-- <br>
<b>Andrew J. Pounds, Ph.D.</b><br>
<i>Professor of Chemistry and Computer Science</i><br>
<i>Director of the Computational Science Program</i><br>
<i>Mercer University, Macon, GA, 31207 (478) 301-5627 </i></div>
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