⭐ 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

📄 tutorial_44.htm

📁 如果你相信它就好好学学吧,同样这里也只是个入门
💻 HTM
📖 第 1 页 / 共 3 页
字号:
🔍
123 
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"><html><head><!-- 这篇文章由Dancingwind翻译，作者的联系方式zhouwei02@mails.tsinghua.edu.cn --><title>NeHe OpenGL教程第四十四课，DancingWind翻译</title>


<meta http-equiv="Content-Type" content="text/html; charset=gb2312">
<style type="text/css">
A:active {
	BACKGROUND: none transparent scroll repeat 0% 0%; COLOR: #bbccff; TEXT-DECORATION: none
}
A:link {
	BACKGROUND: none transparent scroll repeat 0% 0%; COLOR: #bbccff; TEXT-DECORATION: none
}
A:visited {
	BACKGROUND: none transparent scroll repeat 0% 0%; COLOR: #bbccff; TEXT-DECORATION: none
}
A:hover {
	BACKGROUND: none transparent scroll repeat 0% 0%; COLOR: #ffda6a; TEXT-DECORATION: none
}
BODY {
	COLOR: #ffffff; BACKGROUND-COLOR: #000000
}
TD IMG {
	DISPLAY: block
}
.back {
	BACKGROUND: #000022; COLOR: #ffffff
}
.back2 {
	BACKGROUND: #000000; COLOR: #ffffff
}
.back3 {
	BACKGROUND: #000022; COLOR: #ffffff
}
.copy {
	FONT-SIZE: 11px; LINE-HEIGHT: normal; FONT-STYLE: normal; FONT-FAMILY: Tahoma, Verdana, sans-serif; FONT-VARIANT: normal; TEXT-DECORATION: none
}
.head {
	FONT: bold 13px Tahoma, Verdana, sans-serif; TEXT-DECORATION: none
}
.link {
	FONT-SIZE: 14px; LINE-HEIGHT: normal; FONT-STYLE: normal; FONT-FAMILY: Tahoma, Verdana, sans-serif; FONT-VARIANT: normal; TEXT-DECORATION: none
}
.menu {
	FONT: bold 17px Tahoma, Verdana, sans-serif; TEXT-DECORATION: none
}
.news {
	BACKGROUND: #00008b; COLOR: #ffffff
}
.tab {
	PADDING-LEFT: 35px
}
.text {
	FONT-SIZE: 12px; LINE-HEIGHT: normal; FONT-STYLE: normal; FONT-FAMILY: Tahoma, Verdana, sans-serif; FONT-VARIANT: normal; TEXT-DECORATION: none
}
.theme {
	BACKGROUND: none transparent scroll repeat 0% 0%; COLOR: #bbccff
}
.dotted {
	BORDER-RIGHT: #00008b 2px dotted; BORDER-TOP: #00008b 2px dotted; BORDER-LEFT: #00008b 2px dotted; BORDER-BOTTOM: #00008b 2px dotted
}
.solid {
	BORDER-RIGHT: #ffffff 1px solid; BORDER-TOP: #ffffff 1px solid; BORDER-LEFT: #ffffff 1px solid; BORDER-BOTTOM: #ffffff 1px solid
}
.logo {
	BACKGROUND-IMAGE: url(../graphics/rgb/logo.jpg)
}
.menubar {
	BACKGROUND-IMAGE: url(../graphics/rgb/menubar.jpg)
}
.menubg {
	BACKGROUND-IMAGE: url(../graphics/rgb/menubg.jpg)
}
.menuheading {
	BACKGROUND-IMAGE: url(../graphics/rgb/menuheading.jpg)
}
.nehebutton {
	BACKGROUND-IMAGE: url(../graphics/rgb/nehebutton.jpg)
}
.newslogo {
	BACKGROUND-IMAGE: url(../graphics/rgb/newslogo.jpg)
}
.tinylogo {
	BACKGROUND-IMAGE: url(../graphics/rgb/border/tinylogo.jpg)
}
.bc {
	BACKGROUND-IMAGE:  url(../Pic/bc.png)
}
.bl {
	BACKGROUND-IMAGE:  url(../Pic/bl.png)
}
.br {
	BACKGROUND-IMAGE:  url(../Pic/br.png)
}
.c {
	BACKGROUND-IMAGE: url(../Picc.png)
}
.l {
	BACKGROUND-IMAGE:  url(../Pic/l.png)
}
.lc {
	BACKGROUND-IMAGE: url(../Piclc.png)
}
.r {
	BACKGROUND-IMAGE:  url(../Pic/r.png)
}
.rc {
	BACKGROUND-IMAGE: url(../Picrc.png)
}
.tc {
	BACKGROUND-IMAGE:  url(../Pic/tc.png)
}
.tl {
	BACKGROUND-IMAGE:  url(../Pic/tl.png)
}
.tr {
	BACKGROUND-IMAGE:  url(../Pic/tr.png)
}

</style></head><body bgcolor="black" link="#aaccff" text="white" vlink="#aaccff">
<table border="0" cellpadding="0" cellspacing="0" width="100%">
  <tbody>
  <tr>
    <td class="tinylogo" height="130" width="326"><img alt="NeHe Productions" src="Tutorial_44_files/logo.png" height="130" width="326"></td>
      <td align="center" valign="center"><div align="center"><font class="text"><font class="theme" size="+3"><b><i>第44课</i></b></font></font></div></td>
  </tr></tbody></table>
  <!-- 上边框-->
<table border="0" cellpadding="0" cellspacing="0" width="100%">
<tbody>
  <tr>
    <td><img src="Tutorial_44_files/tl.jpg" height="28" width="28"></td>
    <td width="100%"><img src="Tutorial_44_files/tc.gif" height="28" width="100%"></td>
    <td><img src="Tutorial_44_files/tr.gif" height="28" width="28"></td>
  </tr>
</tbody>
</table>

<!-- 中部-->
<table border="0" cellpadding="0" cellspacing="0" width="100%">
<tbody>
  <tr>
  	<!-- 中部左边框-->
    <td background="Tutorial_44_files/l.gif"><img src="Tutorial_44_files/l.gif" height="28" width="28"></td>
	<!-- 中部文字部分-->
    <td valign="top" width="100%">
	<table border="0" width="100%">
          <tbody><tr>
            <td width="20%"><img src="Tutorial_44_files/lesson44.jpg" height="120" width="160"></td>
            <td width="80%"><p><font><b>3D 光晕</b></font><font size="2"><b></b></font></p>
              <p><font size="3">当镜头对准太阳的时候就会出现这种效果，模拟它非常的简单，一点数学和纹理贴图就够了。好好看看吧。</font></p></td>
          </tr>
     </tbody></table>
      </td>
	<!-- 中部右边框-->
    <td background="Tutorial_44_files/r.gif"><img src="Tutorial_44_files/r.gif" height="28" width="28"></td>
  </tr>
</tbody>
</table>

<!-- 下边框-->
<table border="0" cellpadding="0" cellspacing="0" width="100%">
<tbody>
  <tr>
    <td><img src="Tutorial_44_files/bl.gif" height="28" width="28"></td>
    <td width="100%"><img src="Tutorial_44_files/bc.gif" height="28" width="100%"></td>
    <td><img src="Tutorial_44_files/br.gif" height="28" width="28"></td>
  </tr>
</tbody>
</table>
<table border="0" cellpadding="0" cellspacing="0" width="100%">
  <tbody>
  <tr>
    <td class="tl"><img alt="" src="Tutorial_44_files/blank1.gif" height="28" width="28"></td>
    <td class="tc" width="100%"><img alt="" src="Tutorial_44_files/blank1.gif" height="28" width="100%"></td>
    <td class="tr"><img alt="" src="Tutorial_44_files/blank1.gif" height="28" width="28"></td></tr></tbody></table>
<table border="0" cellpadding="0" cellspacing="0" width="100%">
  <tbody>
  <tr>
    <td class="l"><img alt="" src="Tutorial_44_files/blank1.gif" height="28" width="28"></td>
      <td class="back3" valign="top" width="100%">大家好,欢迎来到新的一课,在这一课中我们将扩展glCamera类，来实现镜头光晕的效果。在日常生活中，当我们对着光源看时，会发现强烈的反光。<br>
        为了完成这个效果，我们需要一些数学知识。首先，我们需要一些函数，用来检测某个点或球是否在当前的视景体内。接着我们需要一些纹理作为我们的光晕效果，我们可以把它贴在显示面上。
<p>在我的上一个摄像机类里把下面函数写错了，现在修正如下：</p>
    </td>
    <td class="r"><img alt="" src="Tutorial_44_files/blank1.gif" height="28" width="28"></td></tr></tbody></table>
<table border="0" cellpadding="0" cellspacing="0" width="100%">
  <tbody>
  <tr>
    <td class="bl"><img alt="" src="Tutorial_44_files/blank1.gif" height="28" width="28"></td>
    <td class="bc" width="100%"><img alt="" src="Tutorial_44_files/blank1.gif" height="28" width="28"></td>
    <td class="br"><img alt="" src="Tutorial_44_files/blank1.gif" height="28" width="28"></td></tr></tbody></table>
<pre>void glCamera::SetPrespective()<br>{<br>	GLfloat Matrix[16];												<br>	glVector v;														<br>																	</pre>
<p> <span class="theme">// 根据当前的偏转角旋转视线</span><br>
  glRotatef(m_HeadingDegrees, 0.0f, 1.0f, 0.0f);<br>
  glRotatef(m_PitchDegrees, 1.0f, 0.0f, 0.0f);</p>
<p> <span class="theme">// 返回模型变换矩阵</span><br>
  glGetFloatv(GL_MODELVIEW_MATRIX, Matrix);</p>
<p> <span class="theme">// 获得视线的方向</span><br>
  m_DirectionVector.i = Matrix[8];<br>
  m_DirectionVector.j = Matrix[9];<br>
  m_DirectionVector.k = -Matrix[10];</p>
<p> <span class="theme">// 重置矩阵</span><br>
  glLoadIdentity();</p>
<p> <span class="theme">// 旋转场景</span><br>
  glRotatef(m_PitchDegrees, 1.0f, 0.0f, 0.0f);<br>
  glRotatef(m_HeadingDegrees, 0.0f, 1.0f, 0.0f);</p>
<p> <span class="theme">// 设置当前摄像机的位置</span><br>
  v = m_DirectionVector;<br>
  v *= m_ForwardVelocity;<br>
  m_Position.x += v.i;<br>
  m_Position.y += v.j;<br>
  m_Position.z += v.k;</p>
<p> <span class="theme">// 变换到新的位置</span><br>
  glTranslatef(-m_Position.x, -m_Position.y, -m_Position.z);<br>
  }</p>
<p></p>
<table border="0" cellpadding="0" cellspacing="0" width="100%">
  <tbody>
  <tr>
    <td class="tl"><img alt="" src="Tutorial_44_files/blank1.gif" height="28" width="28"></td>
    <td class="tc" width="100%"><img alt="" src="Tutorial_44_files/blank1.gif" height="28" width="100%"></td>
    <td class="tr"><img alt="" src="Tutorial_44_files/blank1.gif" height="28" width="28"></td></tr></tbody></table>
<table border="0" cellpadding="0" cellspacing="0" width="100%">
  <tbody>
  <tr>
    <td class="l"><img alt="" src="Tutorial_44_files/blank1.gif" height="28" width="28"></td>
      <td class="back3" valign="top" width="100%"> <p>好了，我们现在开始吧。我将使用4个对立的纹理来制造我们的镜头光晕，第一和二个光晕图像被放置在光源处，第三和第四个图像将根据视点的位置和方向动态的生成。纹理的图像如下所示：</p>
      <table align="center" border="0">
        <tbody> 
        <tr> 
          <td align="center"><font class="text">Big Glow<br>
            <br>
            <img src="Tutorial_44_files/big_glow.jpg" height="128" width="128"></font></td>
          <td width="100">&nbsp;</td>
          <td align="center"><font class="text">Streaks<br>
            <br>
            <img src="Tutorial_44_files/streaks.jpg" height="128" width="128"></font></td>
        </tr>
        <tr> 
          <td align="center"><font class="text">Glow<br>
            <br>
            <img src="Tutorial_44_files/glow.jpg" height="64" width="64"></font></td>
          <td width="100">&nbsp;</td>
          <td align="center"><font class="text">Halo<br>
            <br>
            <img src="Tutorial_44_files/halo.jpg" height="64" width="64"></font></td>
        </tr>
        </tbody>
      </table>
      <p>&nbsp;</p>
      <p>&nbsp;</p>
123

⌨️ 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 + -