⭐ 欢迎来到虫虫下载站！ | 📦 资源下载 📁 资源专辑 ℹ️ 关于我们
⭐ 虫虫下载站
📤 上传资源

📄 3.2.2 规格化变换与设备坐标变换.htm

📁 计算机图形学教程计算机图形学教程
💻 HTM
字号:
🔍 
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
<!-- saved from url=(0058)http://www.ekany.com/wdg98/cg/contents/chapter3/les322.htm -->
<HTML xmlns="http://www.w3.org/TR/REC-html40" xmlns:v = 
"urn:schemas-microsoft-com:vml" xmlns:o = 
"urn:schemas-microsoft-com:office:office" xmlns:w = 
"urn:schemas-microsoft-com:office:word"><HEAD><TITLE>3</TITLE>
<META http-equiv=Content-Type content="text/html; charset=GB2312">
<META content=FrontPage.Editor.Document name=ProgId>
<META content="MSHTML 6.00.2800.1106" name=GENERATOR>
<META content="Microsoft Word 9" name=Originator><LINK 
href="les322.files/filelist.xml" rel=File-List><LINK 
href="les322.files/editdata.mso" rel=Edit-Time-Data><LINK 
href="les322.files/oledata.mso" rel=OLE-Object-Data><!--[if !mso]>
<STYLE>v\:* {
	BEHAVIOR: url(#default#VML)
}
o\:* {
	BEHAVIOR: url(#default#VML)
}
w\:* {
	BEHAVIOR: url(#default#VML)
}
.shape {
	BEHAVIOR: url(#default#VML)
}
</STYLE>
<![endif]--><!--[if gte mso 9]><xml> <o:DocumentProperties>  <o:Author>maojian</o:Author>  <o:Template>Normal</o:Template>  <o:LastAuthor>zlj</o:LastAuthor>  <o:Revision>3</o:Revision>  <o:TotalTime>0</o:TotalTime>  <o:Created>2000-04-15T07:28:00Z</o:Created>  <o:LastSaved>1999-04-15T22:45:00Z</o:LastSaved>  <o:Pages>7</o:Pages>  <o:Words>679</o:Words>  <o:Characters>3874</o:Characters>  <o:Company>AI Institute</o:Company>  <o:Lines>32</o:Lines>  <o:Paragraphs>7</o:Paragraphs>  <o:CharactersWithSpaces>4757</o:CharactersWithSpaces>  <o:Version>9.2812</o:Version> </o:DocumentProperties></xml><![endif]--><!--[if gte mso 9]><xml> <w:WordDocument>  <w:DrawingGridVerticalSpacing>7.8 磅</w:DrawingGridVerticalSpacing>  <w:Compatibility>   <w:UseFELayout/>  </w:Compatibility> </w:WordDocument></xml><![endif]-->
<STYLE>@font-face {
	font-family: 宋体;
}
@font-face {
	font-family: 黑体;
}
@font-face {
	font-family: @宋体;
}
@font-face {
	font-family: @黑体;
}
@page  {mso-page-border-surround-header: no; mso-page-border-surround-footer: no; }
@page Section1 {size: 595.3pt 841.9pt; margin: 72.0pt 90.0pt 72.0pt 90.0pt; mso-header-margin: 35.4pt; mso-footer-margin: 35.4pt; mso-paper-source: 0; }
P.MsoNormal {
	FONT-SIZE: 12pt; MARGIN: 0cm 0cm 0pt; FONT-FAMILY: "Times New Roman"; mso-style-parent: ""; mso-pagination: widow-orphan; mso-fareast-font-family: 宋体
}
LI.MsoNormal {
	FONT-SIZE: 12pt; MARGIN: 0cm 0cm 0pt; FONT-FAMILY: "Times New Roman"; mso-style-parent: ""; mso-pagination: widow-orphan; mso-fareast-font-family: 宋体
}
DIV.MsoNormal {
	FONT-SIZE: 12pt; MARGIN: 0cm 0cm 0pt; FONT-FAMILY: "Times New Roman"; mso-style-parent: ""; mso-pagination: widow-orphan; mso-fareast-font-family: 宋体
}
H1 {
	TEXT-JUSTIFY: inter-ideograph; FONT-SIZE: 22pt; MARGIN: 17pt 0cm 16.5pt; LINE-HEIGHT: 28.9pt; FONT-FAMILY: "Times New Roman"; TEXT-ALIGN: justify; mso-pagination: lines-together; mso-style-next: 正文; mso-outline-level: 1; mso-layout-grid-align: none; mso-font-kerning: 22.0pt
}
H2 {
	TEXT-JUSTIFY: inter-ideograph; FONT-SIZE: 16pt; MARGIN: 13pt 0cm; LINE-HEIGHT: 20.8pt; FONT-FAMILY: Arial; TEXT-ALIGN: justify; mso-pagination: lines-together; mso-fareast-font-family: 黑体; mso-style-next: 正文; mso-outline-level: 2; mso-layout-grid-align: none; mso-bidi-font-family: "Times New Roman"
}
H3 {
	TEXT-JUSTIFY: inter-ideograph; FONT-SIZE: 16pt; MARGIN: 13pt 0cm; LINE-HEIGHT: 20.8pt; FONT-FAMILY: "Times New Roman"; TEXT-ALIGN: justify; mso-pagination: lines-together; mso-style-next: 正文; mso-outline-level: 3; mso-layout-grid-align: none
}
A:link {
	COLOR: blue; TEXT-DECORATION: underline; text-underline: single
}
SPAN.MsoHyperlink {
	COLOR: blue; TEXT-DECORATION: underline; text-underline: single
}
A:visited {
	COLOR: purple; TEXT-DECORATION: underline; text-underline: single
}
SPAN.MsoHyperlinkFollowed {
	COLOR: purple; TEXT-DECORATION: underline; text-underline: single
}
P.MsoDocumentMap {
	TEXT-JUSTIFY: inter-ideograph; FONT-SIZE: 10.5pt; BACKGROUND: navy; MARGIN: 0cm 0cm 0pt; LINE-HEIGHT: 15.6pt; FONT-FAMILY: 宋体; TEXT-ALIGN: justify; mso-hansi-font-family: "Times New Roman"; mso-pagination: none; mso-layout-grid-align: none; mso-bidi-font-family: "Times New Roman"
}
LI.MsoDocumentMap {
	TEXT-JUSTIFY: inter-ideograph; FONT-SIZE: 10.5pt; BACKGROUND: navy; MARGIN: 0cm 0cm 0pt; LINE-HEIGHT: 15.6pt; FONT-FAMILY: 宋体; TEXT-ALIGN: justify; mso-hansi-font-family: "Times New Roman"; mso-pagination: none; mso-layout-grid-align: none; mso-bidi-font-family: "Times New Roman"
}
DIV.MsoDocumentMap {
	TEXT-JUSTIFY: inter-ideograph; FONT-SIZE: 10.5pt; BACKGROUND: navy; MARGIN: 0cm 0cm 0pt; LINE-HEIGHT: 15.6pt; FONT-FAMILY: 宋体; TEXT-ALIGN: justify; mso-hansi-font-family: "Times New Roman"; mso-pagination: none; mso-layout-grid-align: none; mso-bidi-font-family: "Times New Roman"
}
DIV.Section1 {
	page: Section1
}
</STYLE>
<!--[if gte mso 9]><xml> <o:shapedefaults v:ext="edit" spidmax="1037"/></xml><![endif]--><!--[if gte mso 9]><xml> <o:shapelayout v:ext="edit">  <o:idmap v:ext="edit" data="1"/> </o:shapelayout></xml><![endif]--></HEAD>
<BODY lang=ZH-CN style="tab-interval: 36.0pt" vLink=purple link=blue>
<H3><FONT size=4><SPAN lang=EN-US><FONT face=楷体_GB2312>3.2.2 </FONT></SPAN><FONT 
face=楷体_GB2312><SPAN 
style="mso-ascii-font-family: Times New Roman; mso-hansi-font-family: Times New Roman">规格化变换与设备坐标变换</SPAN></FONT></FONT></H3>
<P class=MsoNormal><SPAN style="mso-spacerun: yes"><FONT face=楷体_GB2312 
size=4>&nbsp;&nbsp;&nbsp; </FONT></SPAN><FONT size=4><FONT face=楷体_GB2312><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">在计算机图形学中，世界坐标和规格化设备坐标</SPAN><SPAN 
lang=EN-US>(NOrmalized Dovice Coorolinates)</SPAN><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">简称</SPAN><SPAN 
lang=EN-US>NDC)</SPAN><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">是两个同时使用的坐标系统，世界坐标是设计者用描述实际工世界中的设计对象所用的坐标系统，其坐标的范围可以是任意大小的。</SPAN><SPAN 
lang=EN-US>NDC</SPAN><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">是计算机图形软件描给设计对象所用的价值，随着图形硬件的不同，设备的坐标系统也不同，例如有的图形显示器的分辩率只有</SPAN><SPAN 
lang=EN-US>640</SPAN><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">×４８０，而有的高达</SPAN><SPAN 
lang=EN-US>2408</SPAN><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">×</SPAN><SPAN 
lang=EN-US>1024</SPAN><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">。至于绘图机的输出坐标还可以更大。为了使用图形软件于在不同设备之间移植，图形软件并不采用实际的设备坐标，而采用规格化设备坐标</SPAN><SPAN 
lang=EN-US>NDC</SPAN><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">。</SPAN><SPAN 
lang=EN-US>NDC</SPAN><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">定义</SPAN><SPAN 
lang=EN-US>x</SPAN><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">方向和</SPAN><SPAN 
lang=EN-US>y</SPAN><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">方向的变化范围均为</SPAN><SPAN 
lang=EN-US>0</SPAN><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">～</SPAN><SPAN 
lang=EN-US>1</SPAN><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">。从</SPAN><SPAN 
lang=EN-US>NDC</SPAN><SPAN 
style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">到各图形硬件实际坐标之间的映射由图形软件自动实现。因此，使用图形软件的用户均以</SPAN><SPAN 
lang=EN-US>NDC</SPAN><SPAN 
style="mso-ascii-font-family: Times New Roman; mso-hansi-font-family: Times New Roman">在各图形输出与显示设备上作图。</SPAN></FONT></FONT></P>
<P class=MsoNormal><SPAN style="mso-spacerun: yes"><FONT face=楷体_GB2312 
size=4>&nbsp;&nbsp;&nbsp; </FONT></SPAN><FONT size=4><FONT face=楷体_GB2312><SPAN 
style="mso-ascii-font-family: Times New Roman; mso-hansi-font-family: Times New Roman">世界坐标范围是无限大的。为了使</SPAN><SPAN 
lang=EN-US>NDC</SPAN><SPAN 
style="mso-ascii-font-family: Times New Roman; mso-hansi-font-family: Times New Roman">上所显示的世界坐标中物体有一个合适的范围与大小，首先必须对世界坐标指定一个显示范围，它通常是个矩形。这个在世界坐标系中的矩形被称为窗口</SPAN><SPAN 
lang=EN-US>(window)</SPAN><SPAN 
style="mso-ascii-font-family: Times New Roman; mso-hansi-font-family: Times New Roman">。其次，在</SPAN><SPAN 
lang=EN-US>NDC</SPAN><SPAN 
style="mso-ascii-font-family: Times New Roman; mso-hansi-font-family: Times New Roman">上也要指定一个矩形位置来与窗口对应，显示窗口里的内容。这个在</SPAN><SPAN 
lang=EN-US>NDC</SPAN><SPAN 
style="mso-ascii-font-family: Times New Roman; mso-hansi-font-family: Times New Roman">中的矩形被称为视区</SPAN><SPAN 
lang=EN-US>(viewport)</SPAN><SPAN 
style="mso-ascii-font-family: Times New Roman; mso-hansi-font-family: Times New Roman">。图形软件根据窗口与视区的一一对应，自动实现从世界坐标到</SPAN><SPAN 
lang=EN-US>NDC</SPAN><SPAN 
style="mso-ascii-font-family: Times New Roman; mso-hansi-font-family: Times New Roman">的转换。这种从窗口到视区的变换，称为规格化变换</SPAN><SPAN 
lang=EN-US>(Normalization Transformation)</SPAN><SPAN 
style="mso-ascii-font-family: Times New Roman; mso-hansi-font-family: Times New Roman">。</SPAN></FONT></FONT></P>
<P class=MsoNormal>　</P>
<P class=MsoNormal><SPAN lang=EN-US><SPAN style="mso-spacerun: yes"><FONT 
face=楷体_GB2312 size=4>&nbsp;&nbsp;&nbsp; </FONT></SPAN><FONT face=楷体_GB2312 
size=4>(</FONT></SPAN><FONT size=4><FONT face=楷体_GB2312><SPAN 
style="mso-ascii-font-family: Times New Roman; mso-hansi-font-family: Times New Roman">一</SPAN><SPAN 
lang=EN-US>)</SPAN><SPAN 
style="mso-ascii-font-family: Times New Roman; mso-hansi-font-family: Times New Roman">规格化变换</SPAN></FONT></FONT></P>
<P class=MsoNormal><SPAN style="mso-spacerun: yes"><FONT face=楷体_GB2312 
size=4>&nbsp;&nbsp;&nbsp; </FONT></SPAN><FONT size=4><FONT face=楷体_GB2312><SPAN 
style="mso-ascii-font-family: Times New Roman; mso-hansi-font-family: Times New Roman">在图形软件中，定义规格化变换由三条指令构成，它们是：</SPAN></FONT></FONT></P>
<P class=MsoNormal><SPAN lang=EN-US><SPAN style="mso-spacerun: yes"><FONT 
face=楷体_GB2312 size=4>&nbsp;&nbsp;&nbsp; </FONT></SPAN><FONT face=楷体_GB2312 
size=4>1</FONT></SPAN><FONT size=4><FONT face=楷体_GB2312><SPAN 
style="mso-ascii-font-family: Times New Roman; mso-hansi-font-family: Times New Roman">

⌨️ 快捷键说明

复制代码 Ctrl + C
搜索代码 Ctrl + F
全屏模式 F11
切换主题 Ctrl + Shift + D
显示快捷键 ?
增大字号 Ctrl + =
减小字号 Ctrl + -