几何体.htm

此文件是微软MSDN中d3d部分资料的翻译文件

      style="FONT-FAMILY: 宋体; mso-bidi-font-family: 宋体; mso-fareast-language: ZH-CN"><o:p></o:p></SPAN></P></TD>
    <TD 
    style="PADDING-RIGHT: 0.75pt; PADDING-LEFT: 0.75pt; PADDING-BOTTOM: 0.75pt; PADDING-TOP: 0.75pt">
      <P class=MsoNormal><SPAN lang=EN-US 
      style="mso-fareast-language: ZH-CN">sizeof(<B>DWORD</B>)</SPAN><SPAN 
      lang=EN-US 
      style="FONT-FAMILY: 宋体; mso-bidi-font-family: 宋体; mso-fareast-language: ZH-CN"><o:p></o:p></SPAN></P></TD></TR>
  <TR style="mso-yfti-irow: 4">
    <TD 
    style="PADDING-RIGHT: 0.75pt; PADDING-LEFT: 0.75pt; PADDING-BOTTOM: 0.75pt; PADDING-TOP: 0.75pt">
      <P class=MsoNormal><SPAN lang=EN-US 
      style="mso-fareast-language: ZH-CN">D3DFVF_TEX<I>n</I></SPAN><SPAN 
      lang=EN-US 
      style="FONT-FAMILY: 宋体; mso-bidi-font-family: 宋体; mso-fareast-language: ZH-CN"><o:p></o:p></SPAN></P></TD>
    <TD 
    style="PADDING-RIGHT: 0.75pt; PADDING-LEFT: 0.75pt; PADDING-BOTTOM: 0.75pt; PADDING-TOP: 0.75pt">
      <P class=MsoNormal><SPAN lang=EN-US 
      style="mso-fareast-language: ZH-CN">sizeof(<B>float</B>) </SPAN><SPAN 
      style="FONT-FAMILY: 宋体; mso-fareast-language: ZH-CN; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">×</SPAN><SPAN 
      lang=EN-US 
      style="mso-fareast-language: ZH-CN">&nbsp;<I>n</I>&nbsp;</SPAN><SPAN 
      style="FONT-FAMILY: 宋体; mso-fareast-language: ZH-CN; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">×</SPAN><SPAN 
      lang=EN-US style="mso-fareast-language: ZH-CN"> t </SPAN><SPAN lang=EN-US 
      style="FONT-FAMILY: 宋体; mso-bidi-font-family: 宋体; mso-fareast-language: ZH-CN"><o:p></o:p></SPAN></P></TD></TR>
  <TR style="mso-yfti-irow: 5">
    <TD 
    style="PADDING-RIGHT: 0.75pt; PADDING-LEFT: 0.75pt; PADDING-BOTTOM: 0.75pt; PADDING-TOP: 0.75pt">
      <P class=MsoNormal><SPAN lang=EN-US 
      style="mso-fareast-language: ZH-CN">D3DFVF_XYZ</SPAN><SPAN lang=EN-US 
      style="FONT-FAMILY: 宋体; mso-bidi-font-family: 宋体; mso-fareast-language: ZH-CN"><o:p></o:p></SPAN></P></TD>
    <TD 
    style="PADDING-RIGHT: 0.75pt; PADDING-LEFT: 0.75pt; PADDING-BOTTOM: 0.75pt; PADDING-TOP: 0.75pt">
      <P class=MsoNormal><SPAN lang=EN-US 
      style="mso-fareast-language: ZH-CN">sizeof(<B>float</B>) </SPAN><SPAN 
      style="FONT-FAMILY: 宋体; mso-fareast-language: ZH-CN; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">×</SPAN><SPAN 
      lang=EN-US style="mso-fareast-language: ZH-CN"> 3</SPAN><SPAN lang=EN-US 
      style="FONT-FAMILY: 宋体; mso-bidi-font-family: 宋体; mso-fareast-language: ZH-CN"><o:p></o:p></SPAN></P></TD></TR>
  <TR style="mso-yfti-irow: 6; mso-yfti-lastrow: yes">
    <TD 
    style="PADDING-RIGHT: 0.75pt; PADDING-LEFT: 0.75pt; PADDING-BOTTOM: 0.75pt; PADDING-TOP: 0.75pt">
      <P class=MsoNormal><SPAN lang=EN-US 
      style="mso-fareast-language: ZH-CN">D3DFVF_XYZRHW</SPAN><SPAN lang=EN-US 
      style="FONT-FAMILY: 宋体; mso-bidi-font-family: 宋体; mso-fareast-language: ZH-CN"><o:p></o:p></SPAN></P></TD>
    <TD 
    style="PADDING-RIGHT: 0.75pt; PADDING-LEFT: 0.75pt; PADDING-BOTTOM: 0.75pt; PADDING-TOP: 0.75pt">
      <P class=MsoNormal><SPAN lang=EN-US 
      style="mso-fareast-language: ZH-CN">sizeof(<B>float</B>) </SPAN><SPAN 
      style="FONT-FAMILY: 宋体; mso-fareast-language: ZH-CN; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">×</SPAN><SPAN 
      lang=EN-US style="mso-fareast-language: ZH-CN"> 4</SPAN><SPAN lang=EN-US 
      style="FONT-FAMILY: 宋体; mso-bidi-font-family: 宋体; mso-fareast-language: ZH-CN"><o:p></o:p></SPAN></P></TD></TR></TBODY></TABLE>
<P 
style="tab-stops: 45.8pt 91.6pt 137.4pt 183.2pt 229.0pt 274.8pt 320.6pt 366.4pt 412.2pt 458.0pt 503.8pt 549.6pt 595.4pt 641.2pt 687.0pt 732.8pt">顶点格式中出现的纹理坐标的数量由<SPAN 
lang=EN-US>D3DFVF_TEX<I style="mso-bidi-font-style: normal">n</I>标志描述（<I 
style="mso-bidi-font-style: normal">n</I>为从0到8的值）。要计算某个数量的纹理坐标所需要的内存，应该将纹理坐标组的数量乘以每组纹理坐标的大小，每组纹理坐标的大小可以是一到四个浮点数。</SPAN></P>
<P 
style="tab-stops: 45.8pt 91.6pt 137.4pt 183.2pt 229.0pt 274.8pt 320.6pt 366.4pt 412.2pt 458.0pt 503.8pt 549.6pt 595.4pt 641.2pt 687.0pt 732.8pt">要存取某个顶点，应该使用整个顶点的步距增大或减小内存指针。</P>
<H2 
style="tab-stops: 45.8pt 91.6pt 137.4pt 183.2pt 229.0pt 274.8pt 320.6pt 366.4pt 412.2pt 458.0pt 503.8pt 549.6pt 595.4pt 641.2pt 687.0pt 732.8pt">取得顶点缓存描述</H2>
<P 
style="tab-stops: 45.8pt 91.6pt 137.4pt 183.2pt 229.0pt 274.8pt 320.6pt 366.4pt 412.2pt 458.0pt 503.8pt 549.6pt 595.4pt 641.2pt 687.0pt 732.8pt">应用程序可以通过调用<U><SPAN 
lang=EN-US>IDirect3DVertexBuffer9::GetDesc</SPAN></U>方法取得关于一个顶点缓存的信息。这个方法会把关于顶点缓存的信息填入<U><SPAN 
lang=EN-US>D3DVERTEXBUFFER_DESC</SPAN></U>结构的成员。</P>
<DIV class=MsoNormal 
style="TEXT-ALIGN: center; tab-stops: 45.8pt 91.6pt 137.4pt 183.2pt 229.0pt 274.8pt 320.6pt 366.4pt 412.2pt 458.0pt 503.8pt 549.6pt 595.4pt 641.2pt 687.0pt 732.8pt" 
align=center><SPAN lang=EN-US style="mso-fareast-language: ZH-CN">
<HR align=center width="100%" SIZE=1>
</SPAN></DIV>
<P class=MsoNormal 
style="mso-margin-top-alt: auto; mso-margin-bottom-alt: auto; mso-outline-level: 1; tab-stops: 45.8pt 91.6pt 137.4pt 183.2pt 229.0pt 274.8pt 320.6pt 366.4pt 412.2pt 458.0pt 503.8pt 549.6pt 595.4pt 641.2pt 687.0pt 732.8pt"><A 
name=用顶点缓存进行渲染><B><SPAN 
style="FONT-SIZE: 24pt; FONT-FAMILY: 宋体; mso-bidi-font-family: 宋体; mso-font-kerning: 18.0pt; mso-fareast-language: ZH-CN">用顶点缓存进行渲染<SPAN 
lang=EN-US><o:p></o:p></SPAN></SPAN></B></A></P><SPAN 
style="mso-bookmark: 用顶点缓存进行渲染"></SPAN>
<DIV class=MsoNormal 
style="TEXT-ALIGN: center; tab-stops: 45.8pt 91.6pt 137.4pt 183.2pt 229.0pt 274.8pt 320.6pt 366.4pt 412.2pt 458.0pt 503.8pt 549.6pt 595.4pt 641.2pt 687.0pt 732.8pt" 
align=center><SPAN lang=EN-US 
style="FONT-FAMILY: 宋体; mso-bidi-font-family: 宋体; mso-fareast-language: ZH-CN">
<HR align=center width="100%" SIZE=1>
</SPAN></DIV>
<P class=MsoNormal 
style="mso-margin-top-alt: auto; mso-margin-bottom-alt: auto; tab-stops: 45.8pt 91.6pt 137.4pt 183.2pt 229.0pt 274.8pt 320.6pt 366.4pt 412.2pt 458.0pt 503.8pt 549.6pt 595.4pt 641.2pt 687.0pt 732.8pt"><SPAN 
style="FONT-FAMILY: 宋体; mso-bidi-font-family: 宋体; mso-fareast-language: ZH-CN">用顶点缓存渲染顶点数据需要几个步骤。首先，应用程序需要通过调用<U><SPAN 
lang=EN-US>IDirect3DDevice9::SetStreamSource</SPAN></U>方法设置数据流的源，如下示例代码所示。<SPAN 
lang=EN-US><o:p></o:p></SPAN></SPAN></P>
<P class=MsoNormal 
style="tab-stops: 45.8pt 91.6pt 137.4pt 183.2pt 229.0pt 274.8pt 320.6pt 366.4pt 412.2pt 458.0pt 503.8pt 549.6pt 595.4pt 641.2pt 687.0pt 732.8pt"><SPAN 
lang=EN-US 
style="FONT-SIZE: 10pt; FONT-FAMILY: 宋体; mso-bidi-font-family: 宋体; mso-fareast-language: ZH-CN">d3dDevice-&gt;<SPAN 
class=GramE>SetStreamSource(</SPAN> 0, g_pVB, sizeof(CUSTOMVERTEX) 
);<o:p></o:p></SPAN></P>
<P class=MsoNormal 
style="mso-margin-top-alt: auto; mso-margin-bottom-alt: auto; tab-stops: 45.8pt 91.6pt 137.4pt 183.2pt 229.0pt 274.8pt 320.6pt 366.4pt 412.2pt 458.0pt 503.8pt 549.6pt 595.4pt 641.2pt 687.0pt 732.8pt"><B 
style="mso-bidi-font-weight: normal"><SPAN lang=EN-US 
style="FONT-FAMILY: 宋体; mso-bidi-font-family: 宋体; mso-fareast-language: ZH-CN">IDirect3DDevice9::SetStreamSource</SPAN></B><SPAN 
style="FONT-FAMILY: 宋体; mso-bidi-font-family: 宋体; mso-fareast-language: ZH-CN">方法的第一个参数告诉<SPAN 
lang=EN-US>Microsoft&reg; 
Direct3D&reg;设备数据流的源。第二个参数是要绑定到数据流的顶点缓存。第三个参数是成员的大小，以字节为单位。在上面的示例代码中，使用了CUSTOMVERTEX的大小作为成员的大小。<o:p></o:p></SPAN></SPAN></P>
<P class=MsoNormal 
style="mso-margin-top-alt: auto; mso-margin-bottom-alt: auto; tab-stops: 45.8pt 91.6pt 137.4pt 183.2pt 229.0pt 274.8pt 320.6pt 366.4pt 412.2pt 458.0pt 503.8pt 549.6pt 595.4pt 641.2pt 687.0pt 732.8pt"><SPAN 
style="FONT-FAMILY: 宋体; mso-bidi-font-family: 宋体; mso-fareast-language: ZH-CN">下一步是通过调用<U><SPAN 
lang=EN-US>IDirect3DDevice9::SetVertexShader</SPAN></U>方法告诉<SPAN 
lang=EN-US>Direct3D使用哪个顶点着色器。以下示例代码给顶点着色器设置了一个弹性顶点格式（FVF）码。这告诉Direct3D正在处理的顶点类型。<o:p></o:p></SPAN></SPAN></P>
<P class=MsoNormal 
style="tab-stops: 45.8pt 91.6pt 137.4pt 183.2pt 229.0pt 274.8pt 320.6pt 366.4pt 412.2pt 458.0pt 503.8pt 549.6pt 595.4pt 641.2pt 687.0pt 732.8pt"><SPAN 
lang=EN-US 
style="FONT-SIZE: 10pt; FONT-FAMILY: 宋体; mso-bidi-font-family: 宋体; mso-fareast-language: ZH-CN">d3dDevice-&gt;<SPAN 
class=GramE>SetFVF(</SPAN> D3DFVF_CUSTOMVERTEX );<o:p></o:p></SPAN></P>
<P class=MsoNormal 
style="mso-margin-top-alt: auto; mso-margin-bottom-alt: auto; tab-stops: 45.8pt 91.6pt 137.4pt 183.2pt 229.0pt 274.8pt 320.6pt 366.4pt 412.2pt 458.0pt 503.8pt 549.6pt 595.4pt 641.2pt 687.0pt 732.8pt"><SPAN 
style="FONT-FAMILY: 宋体; mso-bidi-font-family: 宋体; mso-fareast-language: ZH-CN">在设置数据流的源和顶点着色器之后，任何绘制方法将使用设定的顶点缓存。以下示例代码显示了如何用<U><SPAN 
lang=EN-US>IDirect3DDevice9::DrawPrimitive</SPAN></U>方法用顶点缓存渲染顶点。<SPAN 
lang=EN-US><o:p></o:p></SPAN></SPAN></P>
<P class=MsoNormal 
style="tab-stops: 45.8pt 91.6pt 137.4pt 183.2pt 229.0pt 274.8pt 320.6pt 366.4pt 412.2pt 458.0pt 503.8pt 549.6pt 595.4pt 641.2pt 687.0pt 732.8pt"><SPAN 
lang=EN-US 
style="FONT-SIZE: 10pt; FONT-FAMILY: 宋体; mso-bidi-font-family: 宋体; mso-fareast-language: ZH-CN">d3dDevice-&gt;<SPAN 
class=GramE>DrawPrimitive(</SPAN> D3DPT_TRIANGLELIST, 0, 1 
);<o:p></o:p></SPAN></P>
<P class=MsoNormal 
style="mso-margin-top-alt: auto; mso-margin-bottom-alt: auto; tab-stops: 45.8pt 91.6pt 137.4pt 183.2pt 229.0pt 274.8pt 320.6pt 366.4pt 412.2pt 458.0pt 503.8pt 549.6pt 595.4pt 641.2pt 687.0pt 732.8pt"><B 
style="mso-bidi-font-weight: normal"><SPAN lang=EN-US 
style="FONT-FAMILY: 宋体; mso-bidi-font-family: 宋体; mso-fareast-language: ZH-CN">IDirect3DDevice9::DrawPrimitive</SPAN></B><SPAN 
style="FONT-FAMILY: 宋体; mso-bidi-font-family: 宋体; mso-fareast-language: ZH-CN">方法接收的第二个参数是顶点缓存中要载入的第一个顶点的索引值。<SPAN 
lang=EN-US><o:p></o:p></SPAN></SPAN></P>
<DIV class=MsoNormal 
style="TEXT-ALIGN: center; tab-stops: 45.8pt 91.6pt 137.4pt 183.2pt 229.0pt 274.8pt 320.6pt 366.4pt 412.2pt 458.0pt 503.8pt 549.6pt 595.4pt 641.2pt 687.0pt 732.8pt" 
align=center><SPAN lang=EN-US 
style="FONT-FAMILY: 宋体; mso-bidi-font-family: 宋体; mso-fareast-language: ZH-CN">
<HR align=center width="100%" SIZE=1>
</SPAN></DIV>
<P class=MsoNormal 
style="mso-margin-top-alt: auto; mso-margin-bottom-alt: auto; mso-outline-level: 1; tab-stops: 45.8pt 91.6pt 137.4pt 183.2pt 229.0pt 274.8pt 320.6pt 366.4pt 412.2pt 458.0pt 503.8pt 549.6pt 595.4pt 641.2pt 687.0pt 732.8pt"><A 
name=FVF顶点缓存><B><SPAN lang=EN-US 
style="FONT-SIZE: 24pt; FONT-FAMILY: 宋体; mso-bidi-font-family: 宋体; mso-font-kerning: 18.0pt; mso-fareast-language: ZH-CN">FVF顶点缓存<o:p></o:p></SPAN></B></A></P><SPAN 
style="mso-bookmark: FVF顶点缓存"></SPAN>
<DIV class=MsoNormal 
style="TEXT-ALIGN: center; tab-stops: 45.8pt 91.6pt 137.4pt 183.2pt 229.0pt 274.8pt 320.6pt 366.4pt 412.2pt 458.0pt 503.8pt 549.6pt 595.4pt 641.2pt 687.0pt 732.8pt" 
align=center><SPAN lang=EN-US 
style="FONT-FAMILY: 宋体; mso-bidi-font-family: 宋体; mso-fareast-language: ZH-CN">
<HR align=center width="100%" SIZE=1>
</SPAN></DIV>
<P class=MsoNormal 
style="mso-margin-top-alt: auto; mso-margin-bottom-alt: auto; tab-stops: 45.8pt 91.6pt 137.4pt 183.2pt 229.0pt 274.8pt 320.6pt 366.4pt 412.2pt 458.0pt 503.8pt 549.6pt 595.4pt 641.2pt 687.0pt 732.8pt"><SPAN 
style="FONT-FAMILY: 宋体; mso-bidi-font-family: 宋体; mso-fareast-language: ZH-CN">把<U><SPAN 
lang=EN-US>IDirect3DDevice9::CreateVertexBuffer</SPAN></U>方法的弹性顶点格式（<SPAN 
lang=EN-US>FVF）参数设置为非零值，但必须是有效的FVF码，表示缓存的内容会通过FVF码描述。用一个FVF码创建的顶点缓存被称为FVF顶点缓存。一些<U>IDirect3DDevice9</U>的方法或用法需要FVF顶点缓存，而另一些需要非FVF顶点缓存。<U>IDirect3DDevice9::ProcessVertices</U>方法需要FVF顶点缓存作为目标顶点缓存参数。<I 
style="mso-bidi-font-style: normal"><o:p></o:p></I></SPAN></SPAN></P>
<P class=MsoNormal 
style="mso-margin-top-alt: auto; mso-margin-bottom-alt: auto; tab-stops: 45.8pt 91.6pt 137.4pt 183.2pt 229.0pt 274.8pt 320.6pt 366.4pt 412.2pt 458.0pt 503.8pt 549.6pt 595.4pt 641.2pt 687.0pt 732.8pt"><SPAN 
lang=EN-US 
style="FONT-FAMILY: 宋体; mso-bidi-font-family: 宋体; mso-fareast-language: ZH-CN">FVF顶点缓存可以被绑定到任意一个编号的源数据流。但是，不允许把FVF顶点缓存用作可编程顶点着色器的输入。<o:p></o:p></SPAN></P>
<P class=MsoNormal 
style="mso-margin-top-alt: auto; mso-margin-bottom-alt: auto; tab-stops: 45.8pt 91.6pt 137.4pt 183.2pt 229.0pt 274.8pt 320.6pt 366.4pt 412.2pt 458.0pt 503.8pt 549.6pt 595.4pt 641.2pt 687.0pt 732.8pt"><SPAN 
lang=EN-US 
style="FONT-FAMILY: 宋体; mso-bidi-font-family: 宋体; mso-fareast-language: ZH-CN">FVF顶点缓存中存在D3DFVF_XYZRHW成员表示缓存中的顶点已经处理过了。用作<B 
style="mso-bidi-font-weight: normal">IDirect3DDevice9::ProcessVertices</B>目标顶点缓存的顶点缓存必须是处理后的。用作固定功能着色器的输入的顶点缓存既可以是处理前的也可以是处理后的。如果顶点缓存是处理后的，那么着色器实际上被略过，数据被直接送到图元裁剪和设置模块。<o:p></o:p></SPAN></P>
<P class=MsoNormal 
style="mso-margin-top-alt: auto; mso-margin-bottom-alt: auto; tab-stops: 45.8pt 91.6pt 137.4pt 183.2pt 229.0pt 274.8pt 320.6pt 366.4pt 412.2pt 458.0pt 503