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Strip comments and inline ids onto h*

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James Gregory 2013-12-30 15:11:04 +11:00
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@ -10,16 +10,9 @@
<meta name="vspubdate" content="07/01/97" />
<meta name="vscategory" content="Web and Software Development: Game Development,Web and Software Development: Graphics and Multimedia Development" />
<title>Michael Abrash's Graphics Programming Black Book Special Edition: Bresenham Is Fast, and Fast Is Good</title><!-- HEADER -->
<!-- Empty Reference Subhead -->
<!--ISBN=1576101746//-->
<!--TITLE=Michael Abrash's Graphics Programming Black Book Special Edition//-->
<!--AUTHOR=Michael Abrash//-->
<!--PUBLISHER=The Coriolis Group, Inc.//-->
<title>Michael Abrash's Graphics Programming Black Book Special Edition: Bresenham Is Fast, and Fast Is Good</title>
<meta name="chapter" content="35" />
<meta name="pages" content="664-667" />
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</head>
<body>
@ -37,7 +30,7 @@
<p><br /></p>
<p><b>LISTING 35.2 L35-2.C</b></p><!-- CODE //-->
<p><b>LISTING 35.2 L35-2.C</b></p>
<pre>
/*
* Sample program to illustrate EGA/VGA line drawing routines.
@ -122,9 +115,9 @@ void main()
_AX = TEXT_MODE;
geninterrupt(BIOS_VIDEO_INT);
}
</pre><!-- END CODE //-->
</pre>
<h4 align="left"><a id="Heading7"></a>Looking at EVGALine</h4>
<h4 align="left" id="Heading7">Looking at EVGALine</h4>
<p>The <b>EVGALine</b> function itself performs four operations. <b>EVGALine</b> first sets up the VGA&rsquo;s hardware so that all pixels drawn will be in the desired color. This is accomplished by setting two of the VGA&rsquo;s registers, the Enable Set/Reset register and the Set/Reset register. Setting the Enable Set/Reset to the value 0FH, as is done in <b>EVGALine</b>, causes all drawing to produce pixels in the color contained in the Set/Reset register. Setting the Set/Reset register to the passed color, in conjunction with the Enable Set/Reset setting of 0FH, causes all drawing done by <b>EVGALine</b> and the functions it calls to generate the passed color. In summary, setting up the Enable Set/Reset and Set/Reset registers in this way causes the remainder of <b>EVGALine</b> to draw a line in the specified color.</p>
@ -142,9 +135,8 @@ void main()
<p>Similarly, octants 0 (where X increases from start to finish) and 3 (where X decreases from start to finish) differ only in the direction in which the X coordinate moves when it changes. The difference between line drawing in octants 0 and 3 and line drawing in octants 1 and 2 is that in octants 0 and 3, since X is the major axis, the X coordinate changes on every pixel of the line and the Y coordinate changes only when the running error of the line dictates. In octants 1 and 2, the Y coordinate changes on every pixel and the X coordinate changes only when the running error dictates, since Y is the major axis.</p>
<p><a id="Fig4"><!-- </A><A HREF="javascript:displayWindow('images/35-04.jpg',408,247 )"> --><img src="images/35-04.jpg" /><br />
<!-- </A>
<BR><A HREF="javascript:displayWindow('images/35-04.jpg',408,247)"> --><b>Figure 35.4</b></a>&nbsp;&nbsp;<i>Bresenham&rsquo;s eight possible line orientations.</i></p>
<p><a id="Fig4"><img src="images/35-04.jpg" /><br />
<b>Figure 35.4</b></a>&nbsp;&nbsp;<i>Bresenham&rsquo;s eight possible line orientations.</i></p>
<p><br /></p>
@ -163,10 +155,6 @@ void main()
<div align="center">
Graphics Programming Black Book &copy; 2001 Michael Abrash
</div><!-- all of the reference materials (books) have the footer and subfoot reveresed -->
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</body>
</html>