Question

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);
}

void CGeneric2View::drawb_curve(void)
{
myinit();
GLfloat points[4][3]={
{-0.6,-0.6,0.0},
{-0.4,0.6,0.0},
{0.4,-0.6,0.0},
{0.6,0.6,0.0}
};
glMap1f(GL_MAP1_VERTEX_3,0.0,1.0,3,4,&points[0][0]);
glEnable(GL_MAP1_VERTEX_3);
glShadeModel(GL_FLAT);
glClear(GL_COLOR_BUFFER_BIT|GL_DEPTH_BUFFER_BIT);
glColor3f(0.0,0.0,1.0);
glLineWidth(5.0);
glBegin(GL_LINE_STRIP);
int i;
for(i=0;i<=30;i++)
glEvalCoord1f((GLfloat)i/30.0);
glEnd();
glPointSize(10.0);
glColor3f(1.0,0.0,0.0);
glBegin(GL_POINTS);
for(i=0;i<=4;i++)
glVertex3fv(&points[i][0]);
glEnd();
glFlush();

}

Answer 1

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);

追问

我知道了，刚刚看了一下原来是在HGLRC这边法赋值出了问题，谢谢了！

追答

还有你的SwapBuffers(hDC);在wglMakeCurrent(NULL,NULL);之后,我不确定这样好不好,因为我没试过.最好是画完图直接交换缓冲区.