在opengl中编写的程序没有错误,可是就是不显示图形

void CGeneric2View::OnDrawBezierCurve()

{

// TODO: 在此添加命令处理程序代码

HWND hWnd=GetSafeHwnd()

HDC hDC=::GetDC(hWnd)

wglMakeCurrent(hDC,hglrc)

drawb_curve()

wglMakeCurrent(NULL,NULL)

SwapBuffers(hDC)

}

我怎么没有看到HGLRC的赋值过程?

wglCreateContext(hDC)

#include <windows.h>

#include <stdio.h>

#include <string.h>

#include <stdlib.h>

#include <math.h>

#include <time.h>

#include "glut.h"

static GLfloat spin = 0.0

void init( void )

{

glClearColor( 0.0, 0.0, 0.0, 0.0 )

glShadeModel( GL_FLAT )

}

void display( void )

{

glClear( GL_COLOR_BUFFER_BIT )

glPushMatrix( )

glRotatef( spin, 0.0, 0.0, 1.0 )

glColor3f( 1.0, 1.0, 1.0 )

glRectf( -25.0, -25.0, 25.0, 25.0 )

glPopMatrix( )

glutSwapBuffers( )

}

void spinDisplay( void )

{

spin = spin + 2.0

if ( spin >360.0 )

spin = spin - 360.0

glutPostRedisplay( )

}

void reshape( int w, int h )

{

glViewport( 0, 0, (GLsizei)w, (GLsizei)h )

glMatrixMode( GL_PROJECTION )

glLoadIdentity( )

//void glOrtho(GLdouble left,GLdouble right,GLdouble bottom,GLdouble top,GLdouble near,GLdouble far)

glOrtho( -50.0, 50.0, -50.0, 50.0, -1.0, 1.0 )

glMatrixMode( GL_MODELVIEW )

glLoadIdentity( )

}

void mouse( int button, int state, int x, int y )

{

switch ( button )

{

case GLUT_LEFT_BUTTON:

if ( state == GLUT_DOWN )

glutIdleFunc( spinDisplay )

break

case GLUT_MIDDLE_BUTTON:

if ( state == GLUT_DOWN )

glutIdleFunc( 0 )

break

default:

break

}

}

void keyboard( unsigned char key, int x, int y )

{

switch (key)

{

case 'a':

glutIdleFunc( spinDisplay )

break

case 's':

glutIdleFunc( 0 )

break

}

}

int main( int argc, char** argv )

{

glutInit( &argc, argv )

glutInitDisplayMode( GLUT_DOUBLE | GLUT_RGB )

glutInitWindowSize( 250, 250 )

glutInitWindowPosition( 100, 100 )

glutCreateWindow( argv [0] )

init( )

glutDisplayFunc( display )

glutReshapeFunc( reshape )

glutMouseFunc( mouse )

glutKeyboardFunc( keyboard )

glutMainLoop( )

return 0

}

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