OpenGL里画线

xShandow

<>在OpenGL里画线语句:
: |/ E6 |. t+ g9 ^glBegin(GL_LINES);
   glVertex2f(x,y);
   glVertex2f(a,b);
glEnd();</P>
<>注意:目前只讨论OpenGL 2D模式.
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下面是一个画线实例和效果图
#define GL_PI 3.1415f</P>
<>void Draw()
# I9 }9 ^, @; Y{
GLfloat x,y,angle;</P>
6 u5 I8 D0 X9 L<> glPushMatrix();</P>
8 o! _3 F2 g" o/ I9 \4 M  [4 d7 b<> glTranslatef(300,200,0);
& \- q. c# i3 ^ glColor3f(0.6f,0.6f,0.1f);
& n( s5 h8 V4 ^" ^# { glBegin(GL_LINES);
  for(angle=0.0f;angle&lt;3*GL_PI;angle+=0.5f)
  t8 {% {2 g5 f5 @) Z  Y  {
   x=150.0f*sin(angle);
   y=150.0f*cos(angle);</P>
+ ?2 o# L* j" B5 K: ?<>   glVertex2f(x,y);</P>
6 }: a' M. R% ~<>   x=150.0f*sin(angle+3.1415f);
  b& m% }1 I$ P2 _/ A   y=150.0f*cos(angle+3.1415f);
* A* x3 a  i' N3 e' w  J6 g   glVertex2f(x,y);
3 a+ e! L2 I% q7 o, ]( X6 W2 X% v5 B: t  }
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glEnd();</P>
<> glPopMatrix();
}
</P>