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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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31-05.html
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<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: Higher 256-Color Resolution on the VGA</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: Higher 256-Color Resolution on the VGA</title>
<meta name="chapter" content="31" />
<meta name="pages" content="600-605" />
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</head>
<body>
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<p><br /></p>
<p><b>LISTING 31.2 L31-2.ASM</b></p><!-- CODE //-->
<p><b>LISTING 31.2 L31-2.ASM</b></p>
<pre>
; Program to demonstrate the two pages available in 320x400
; 256-color modes on a VGA. Draws diagonal color bars in all
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</pre><!-- END CODE //-->
</pre>
<p>When you run Listing 31.2, note the extremely smooth edges and fine gradations of color, especially in the screens with slanting color bars. The displays produced by Listing 31.2 make it clear that 320x400 256-color mode can produce effects that are simply not possible in any 16-color mode.</p>
<h3><a id="Heading8"></a>Something to Think About</h3>
<h3 id="Heading8">Something to Think About</h3>
<p>You can, if you wish, use the display memory organization of 320x400 mode in 320x200 mode by modifying <b>Set320x400Mode</b> to leave the maximum scan line setting at 1 in the mode set. (The version of <b>Set320x400Mode</b> in Listings 31.1 and 31.2 forces the maximum scan line to 0, doubling the effective resolution of the screen.) Why would you want to do that? For one thing, you could then choose from not two but <i>four</i> 320x200 256-color display pages, starting at offsets 0, 4000H, 8000H, and 0C000H in display memory. For another, having only half as many pixels per screen can as much as double drawing speeds; that&rsquo;s one reason that many games run at 320x200, and even then often limit the active display drawing area to only a portion of the screen.</p>
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<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>