]]>妯″瀷瑙嗗浘鍙樻崲鏃訛紝娉曠嚎鍚戦噺瑕佷箻妯″瀷瑙嗗浘鐭╅樀鐨勯嗚漿緗煩闃?/title><link>http://www.shnenglu.com/flushthink/archive/2009/11/19/101380.html</link><dc:creator>tiny</dc:creator><author>tiny</author><pubDate>Thu, 19 Nov 2009 06:38:00 GMT</pubDate><guid>http://www.shnenglu.com/flushthink/archive/2009/11/19/101380.html</guid><wfw:comment>http://www.shnenglu.com/flushthink/comments/101380.html</wfw:comment><comments>http://www.shnenglu.com/flushthink/archive/2009/11/19/101380.html#Feedback</comments><slash:comments>4</slash:comments><wfw:commentRss>http://www.shnenglu.com/flushthink/comments/commentRss/101380.html</wfw:commentRss><trackback:ping>http://www.shnenglu.com/flushthink/services/trackbacks/101380.html</trackback:ping><description><![CDATA[鏃╁墠涓鐩磋榪欎釜闂鍥版儜錛屼絾鏄嚜宸辨帹鍊掍簡(jiǎn)寰堝閬嶄篃娌℃帹鍑烘潵銆?br>鍝庯紝鍦╣ameres涓婃悳浜?騫村墠鐨勮皥璇濓紝鍚庢潵鍦╣amedev鎼滃埌浜?jiǎn)绛旀銆?br>鍏跺疄鍦ㄨ綆楁満鍥懼艦瀛︿腑錛屽彧瑕佹槸鍙樻崲錛屾棤璁哄鉤縐伙紝鏃嬭漿錛岀緝鏀撅紝閮芥槸涔樹(shù)竴涓煩闃點(diǎn)?br>鍦ㄦā鍨嬭鍥懼彉鎹㈡椂錛岄《鐐逛箻妯″瀷瑙嗗浘鍙樻崲鐭╅樀錛岃岄《鐐瑰搴旂殑欏剁偣娉曠嚎鍚戦噺錛堟垨鍏朵粬鐨勬硶綰垮悜閲忥級(jí)鍒欒涔樻ā鍨嬭鍥劇煩闃電殑閫嗚漿緗煩闃點(diǎn)?br>欏剁偣鍜屾硶綰塊兘鏄悜閲忥紝浠栦滑鐨勫尯鍒槸浠涔堬紵鏃犻潪欏剁偣鏄?lt;x, y, z>琛ㄧず緙虹渷鐨?lt;x, y, z, 1>錛岃屾硶綰垮悜閲忔槸<x, y, z>琛ㄧず緙虹渷鐨?lt;x, y, z, 0>銆傚叧浜庝負(fù)浠涔堟槸榪欐牱錛屼笉鐢ㄦ垜璇翠簡(jiǎn)鍚э紝2涓《鐐瑰悜閲忓噺涓嬬湅鐪嬪氨鐭ラ亾浜?jiǎn)銆?br>浠庤繖鐐規(guī)潵鐪嬶紝紜疄涓嶅悓錛屾垨璁稿氨鏄繖涓笉鍚岋紝閫犳垚浜?jiǎn)鍙樻崲鐨勪笉鍚屽惂銆?br>娉曠嚎鍚戦噺鍙兘淇濊瘉鏂瑰悜鐨勪竴鑷存э紝鑰屼笉鑳戒繚璇佷綅緗殑涓鑷存э紝鎵浠ワ紝鎵鏈夌嚎鍚戦噺蹇呴』浠ラ潰鐨勫艦寮忚繘琛屽彉鎹紝濡備笅錛?br>
<h2>Transforming Planes</h2>
<p>If we have a plane vector <strong>n</strong> = [a, b, c, d] which describes a plane then for any point <strong>p</strong> = [x, y, z, 1] in that plane the follow equation holds:</p>
<p><strong>n</strong><sup>t</sup> <strong>p</strong> = ax + by + cz + d = 0 </p>
<p>If for a point <strong>p</strong> on the plane, we apply an invertible transformation <strong>R</strong> to get the transformed point <strong>p<sub>1</sub></strong>, then the plane vector <strong>n<sub>1</sub></strong> of the transformed plane is given by applying a corresponding transformation <strong>Q</strong> to the original plane vector <strong>n</strong> where <strong>Q</strong> is unknown.
<p><strong>p<sub>1</sub></strong> = <strong>R</strong> <strong>p</strong> <br><strong>n<sub>1</sub></strong> = <strong>Q</strong> <strong>n</strong> <br></p>
We can solve for <strong>Q</strong> by using the resulting plane equation: <br>
<p><strong>n<sub>1</sub></strong><sup>t</sup> <strong>p<sub>1</sub></strong> = 0 <br></p>
Begin by substituting for <strong>n<sub>1</sub></strong> and <strong>p<sub>1</sub></strong>: <br>
<p>(<strong>Q</strong> <strong>n</strong>)<sup>t</sup> (<strong>R</strong> <strong>p</strong>) = 0 <br><strong>n</strong><sup>t</sup> <strong>Q</strong><sup>t</sup> <strong>R</strong> <strong>p</strong> = 0 <br></p>
If <strong>Q</strong><sup>t</sup> <strong>R</strong> = <strong>I</strong> then <strong>n</strong><sup>t</sup> <strong>Q</strong><sup>t</sup> <strong>R</strong> <strong>p</strong> = <strong>n</strong><sup>t</sup> <strong>I</strong> <strong>p</strong> = <strong>n</strong><sup>t</sup> <strong>p</strong> = 0 which is given.<br>
<p><strong>Q</strong><sup>t</sup> <strong>R</strong> = <strong>I</strong> <br><strong>Q</strong><sup>t</sup> = <strong>R</strong><sup>-1</sup> <br><strong>Q</strong> = (<strong>R</strong><sup>-1</sup>)<sup>t</sup> <br></p>
Substituting <strong>Q</strong> back into our plane vector transformation equation we get: <br>
<p><strong>n<sub>1</sub></strong> = <strong>Q</strong> <strong>n</strong> = (<strong>R</strong><sup>-1</sup>)<sup>t</sup> <strong>n</strong> </p>
<img src ="http://www.shnenglu.com/flushthink/aggbug/101380.html" width = "1" height = "1" /><br><br><div align=right><a style="text-decoration:none;" href="http://www.shnenglu.com/flushthink/" target="_blank">tiny</a> 2009-11-19 14:38 <a href="http://www.shnenglu.com/flushthink/archive/2009/11/19/101380.html#Feedback" target="_blank" style="text-decoration:none;">鍙戣〃璇勮</a></div>]]></description></item><item><title>compiler opthttp://www.shnenglu.com/flushthink/archive/2009/11/10/100551.htmltinytinyMon, 09 Nov 2009 23:25:00 GMThttp://www.shnenglu.com/flushthink/archive/2009/11/10/100551.htmlhttp://www.shnenglu.com/flushthink/comments/100551.htmlhttp://www.shnenglu.com/flushthink/archive/2009/11/10/100551.html#Feedback0http://www.shnenglu.com/flushthink/comments/commentRss/100551.htmlhttp://www.shnenglu.com/flushthink/services/trackbacks/100551.html鍏徃鐨勫鉤鍙板彧緙栬瘧浜?jiǎn)release鐗堬紝鎴戜滑灝卞繀欏誨湪release涓嬪啓鍏蜂綋瀹炵幇銆傦紙渚濊禆release鍐檇ebug浼?xì)鍑洪棶棰樺Q?br>鍙伓鐨勬槸錛屾垜鐨勪唬鐮佸璞″眰嬈￠澶氾紝鎵浠ユ垜鍐欎簡(jiǎn)寰堝灝忓嚱鏁幫紝榪欎簺灝忓嚱鏁板湪release鐗堟湰涓嬮粯璁ゆ槸鍐呰仈鐨勩?br>灝辮繖鏍烽犳垚浜?jiǎn)鎮(zhèn)插墽锛寴q囧鐨勫唴鑱旓紝鎶婅皟璇曞櫒閮芥檭鏅曚簡(jiǎn)錛岀儲(chǔ)鎬э紝鎴戞妸緙栬瘧浼樺寲鍏充簡(jiǎn)錛屽彂鐜癲ll鑶ㄨ儉鍒?鍊嶃?br>
