OpenGL里画线

xShandow

<>在OpenGL里画线语句:
glBegin(GL_LINES);
   glVertex2f(x,y);
4 q: O0 ^/ |% |( ]5 ^9 q+ H   glVertex2f(a,b);
( f6 u5 J2 x& e# r, FglEnd();</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
  `8 M2 j* K" u) ?1 ~( F5 g+ y#define GL_PI 3.1415f</P>
" b; H" q' x2 s9 ^- }  U<>void Draw()
/ \8 B# D* W+ a" ]+ u2 L& E{
. ~+ m) H; q* u9 D* L GLfloat x,y,angle;</P>
4 R; {8 T: V6 s- W1 K/ G<> glPushMatrix();</P>
<> glTranslatef(300,200,0);
8 \/ N, e' W" N) M* h- q glColor3f(0.6f,0.6f,0.1f);
glBegin(GL_LINES);
  for(angle=0.0f;angle&lt;3*GL_PI;angle+=0.5f)
& \8 H6 k4 O. n! p& \  {
   x=150.0f*sin(angle);
   y=150.0f*cos(angle);</P>
7 y) O  m4 J8 j6 e8 B: [<>   glVertex2f(x,y);</P>
<>   x=150.0f*sin(angle+3.1415f);
8 ?! b: N; Y/ E" T. o+ b* k   y=150.0f*cos(angle+3.1415f);
+ |' \7 y( o  w8 ]0 W   glVertex2f(x,y);
) _) Q1 }6 `4 b0 o1 Q( q; I; o  }
5 P  |/ l7 {( }! i% T& x1 Y  
7 E8 w  q/ h% } glEnd();</P>
9 ]) q* f0 \0 b6 ?2 o/ M<> glPopMatrix();
- X5 k9 d! U; \" w  e- t}
8 M9 v6 K* ~# A  N</P>