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		<id>https://wiki.kram.nz/index.php?title=CS372&amp;diff=58&amp;oldid=prev</id>
		<title>Mark: New page: == 2006 Exam Answers ==  1 a  2 b  3 b  4 d  5 b  6 c  &#039;&#039;&#039;jtho153&#039;&#039;&#039;  The line and the plane are parallel ( The planes normal and the line vector are orthagonal ).   So we can just find th...</title>
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		<updated>2008-02-15T19:57:28Z</updated>

		<summary type="html">&lt;p&gt;New page: == 2006 Exam Answers ==  1 a  2 b  3 b  4 d  5 b  6 c  &amp;#039;&amp;#039;&amp;#039;jtho153&amp;#039;&amp;#039;&amp;#039;  The line and the plane are parallel ( The planes normal and the line vector are orthagonal ).   So we can just find th...&lt;/p&gt;
&lt;p&gt;&lt;b&gt;New page&lt;/b&gt;&lt;/p&gt;&lt;div&gt;== 2006 Exam Answers ==&lt;br /&gt;
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1 a&lt;br /&gt;
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2 b&lt;br /&gt;
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3 b&lt;br /&gt;
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4 d&lt;br /&gt;
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5 b&lt;br /&gt;
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6 c&lt;br /&gt;
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&amp;#039;&amp;#039;&amp;#039;jtho153&amp;#039;&amp;#039;&amp;#039;&lt;br /&gt;
 The line and the plane are parallel ( The planes normal and the line vector are orthagonal ). &lt;br /&gt;
 So we can just find the distance from point on the line to the plane.&lt;br /&gt;
 &lt;br /&gt;
 Easiest point = (2,1,0).&lt;br /&gt;
 &lt;br /&gt;
 Distance = |n.p| / |n|&lt;br /&gt;
  = 4 / √21&lt;br /&gt;
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7 c&lt;br /&gt;
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8 d&lt;br /&gt;
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9 d&lt;br /&gt;
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&amp;#039;&amp;#039;&amp;#039;jtho153&amp;#039;&amp;#039;&amp;#039;&lt;br /&gt;
 | y^2 + 3*e^(xz)*z |&lt;br /&gt;
 |      2xy         |&lt;br /&gt;
 |  3*e^(xz)*x - 1  |&lt;br /&gt;
&lt;br /&gt;
10 &amp;#039;&amp;#039;&amp;#039;arob136&amp;#039;&amp;#039;&amp;#039;: B -&amp;gt; I subsituted (1, 0) for (s, t) &lt;br /&gt;
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&amp;#039;&amp;#039;&amp;#039;jtho153&amp;#039;&amp;#039;&amp;#039;: A&lt;br /&gt;
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&amp;#039;&amp;#039;&amp;#039;jtho153&amp;#039;&amp;#039;&amp;#039;&lt;br /&gt;
 I can only find in the notes how to get the tangent of a parametric equation with 1 parameter. But because its multi-choice you can figure it out :P.&lt;br /&gt;
 s&amp;#039;= (1,0,2s) = (1,0,2)&lt;br /&gt;
 t&amp;#039;= (0,1,-e^t) =(0,1,-1)&lt;br /&gt;
 n = s&amp;#039; x t&amp;#039; = (-2,1,1) &lt;br /&gt;
 &lt;br /&gt;
 Cross the tangents of both parameters, at the point, and you should get the normal. &lt;br /&gt;
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11 c&lt;br /&gt;
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12 a&lt;br /&gt;
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13 b&lt;br /&gt;
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14 a&lt;br /&gt;
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&amp;#039;&amp;#039;&amp;#039;jtho153&amp;#039;&amp;#039;&amp;#039;&lt;br /&gt;
 Cross product gives you an othagonal vector, dotted with either u or v will give you 0.&lt;br /&gt;
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15 d&lt;br /&gt;
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16 &amp;#039;&amp;#039;&amp;#039;ezur001&amp;#039;&amp;#039;&amp;#039; a. texture coords of (10,10) is (1,1)&lt;br /&gt;
&lt;br /&gt;
17 d None of the above, should be over √14 &lt;br /&gt;
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18 c&lt;br /&gt;
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19 a&lt;br /&gt;
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&amp;#039;&amp;#039;&amp;#039;jtho153&amp;#039;&amp;#039;&amp;#039;&lt;br /&gt;
                 *     &lt;br /&gt;
                 ^ Q    ^&lt;br /&gt;
                 |      |&lt;br /&gt;
             ^   |      |&lt;br /&gt;
             |n  | h    |&lt;br /&gt;
       ______|___|_     | H&lt;br /&gt;
      /      |   | \    |&lt;br /&gt;
     |       *c  *a |   |&lt;br /&gt;
      \____________/    |&lt;br /&gt;
             ^          |&lt;br /&gt;
             |          |&lt;br /&gt;
             |d         |&lt;br /&gt;
             |          |&lt;br /&gt;
    (origin) o ----------&lt;br /&gt;
            &lt;br /&gt;
 |a-c| &amp;lt; r&lt;br /&gt;
 a = Q - c&lt;br /&gt;
 a = Q - h&lt;br /&gt;
 h = H - d&lt;br /&gt;
 H = (Q.n) * n&lt;br /&gt;
 d = (n.c) * n&lt;br /&gt;
 h = (Q.n - n.c) * n&lt;br /&gt;
 |Q - (Q.n - n.c) * n - c| &amp;lt; r&lt;br /&gt;
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20 b&lt;br /&gt;
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21 &amp;#039;&amp;#039;&amp;#039;bcar066&amp;#039;&amp;#039;&amp;#039;: d  Stunt him is C - clai049&lt;br /&gt;
&lt;br /&gt;
&amp;#039;&amp;#039;&amp;#039;arob136&amp;#039;&amp;#039;&amp;#039;: B -&amp;gt; translate by 1, then scale and rotate &lt;br /&gt;
&lt;br /&gt;
22 &amp;#039;&amp;#039;&amp;#039;jtho153&amp;#039;&amp;#039;&amp;#039;: b (&amp;#039;&amp;#039;&amp;#039;jtho153&amp;#039;&amp;#039;&amp;#039; could be (a) not 100% sure )&lt;br /&gt;
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&amp;#039;&amp;#039;&amp;#039;aols010&amp;#039;&amp;#039;&amp;#039;: d&lt;br /&gt;
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&amp;#039;&amp;#039;&amp;#039;jtho153&amp;#039;&amp;#039;&amp;#039;&lt;br /&gt;
 (i)&lt;br /&gt;
 Don&amp;#039;t even know if we&amp;#039;re meant to know about extents but its like the view volume.&lt;br /&gt;
 If you use them but all your objects end up inside it anyway then you&amp;#039;ve just wasted time checking it.&lt;br /&gt;
 &lt;br /&gt;
 So yeah it can slow it down.&lt;br /&gt;
 &lt;br /&gt;
 (ii)&lt;br /&gt;
 False, just examine the square of the distances. Square root is too expensive.&lt;br /&gt;
 &lt;br /&gt;
 (iii)&lt;br /&gt;
 I&amp;#039;m not 100% sure but like it makes sense. There may be some exception.&lt;br /&gt;
&lt;br /&gt;
&amp;#039;&amp;#039;&amp;#039;aols010&lt;br /&gt;
 Extents sounds like a way of only testing if rays hit complex objects by first testing if the ray is within a simple extent, &lt;br /&gt;
 eg a sphere or a cube. That sounds faster. You can look it up and tell me how good a guesser I am sometime. &lt;br /&gt;
&lt;br /&gt;
23 ? [inside sets? not even in the notes]&lt;br /&gt;
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24 &amp;#039;&amp;#039;&amp;#039;aols010&amp;#039;&amp;#039;&amp;#039;: guess=b?&lt;br /&gt;
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25 [no longer examinable]&lt;br /&gt;
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26 [no longer examinable]&lt;br /&gt;
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27 d&lt;br /&gt;
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28 a&lt;br /&gt;
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29 c&lt;br /&gt;
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30 &amp;#039;&amp;#039;&amp;#039;aols010&amp;#039;&amp;#039;&amp;#039;: a or c (are surface normals affected at all by translations (or crazy transposes of translations)? if not then c). &lt;br /&gt;
&lt;br /&gt;
31 ?&lt;br /&gt;
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32 b&lt;br /&gt;
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33 b&lt;br /&gt;
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34 a&lt;br /&gt;
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35 ? [whats image precision?]&lt;br /&gt;
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36 a&lt;br /&gt;
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37 d&lt;br /&gt;
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38 d&lt;br /&gt;
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39 c&lt;br /&gt;
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40 a&lt;br /&gt;
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41 ? [&amp;quot;dir&amp;quot;?]&lt;br /&gt;
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42 d&lt;br /&gt;
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43 c&lt;br /&gt;
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44 b&lt;br /&gt;
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45 b (or d if &amp;quot;positive&amp;quot; == &amp;quot;non negative&amp;quot;)&lt;br /&gt;
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46 [no longer examinable]&lt;br /&gt;
&lt;br /&gt;
47 [no longer examinable]&lt;br /&gt;
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48 [no longer examinable]&lt;br /&gt;
&lt;br /&gt;
49 D&lt;br /&gt;
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50 D object gets brighter as more blue is added, bringing it closer to white.&lt;/div&gt;</summary>
		<author><name>Mark</name></author>
	</entry>
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