求助 我这个关于OpenGL基于MFC的画线怎么画不出呢？谢谢
#include "stdafx.h"
#include "F.h"
#include "FDoc.h"
#include "FView.h"
#include "MainFrm.h"
#ifdef _DEBUG
#define new DEBUG_NEW
#undef THIS_FILE
static char THIS_FILE[] = __FILE__;
#endif
/////////////////////////////////////////////////////////////////////////////
// CFView
IMPLEMENT_DYNCREATE(CFView, CView)
BEGIN_MESSAGE_MAP(CFView, CView)
//{{AFX_MSG_MAP(CFView)
ON_WM_CREATE()
ON_WM_CANCELMODE()
ON_WM_DESTROY()
ON_WM_MOUSEMOVE()
ON_COMMAND(ID_BUTTONnurbs, OnBUTTONnurbs)
ON_COMMAND(ID_BUTTONbezier, OnBUTTONbezier)
//}}AFX_MSG_MAP
// Standard printing commands
ON_COMMAND(ID_FILE_PRINT, CView::OnFilePrint)
ON_COMMAND(ID_FILE_PRINT_DIRECT, CView::OnFilePrint)
ON_COMMAND(ID_FILE_PRINT_PREVIEW, CView::OnFilePrintPreview)
END_MESSAGE_MAP()
/////////////////////////////////////////////////////////////////////////////
// CFView construction/destruction
CFView::CFView()
{
// TODO: add construction code here
my_pDC=NULL;
mybezier=FALSE;
mynurbs=FALSE;
}
CFView::~CFView()
{
}
BOOL CFView::PreCreateWindow(CREATESTRUCT& cs)
{
// TODO: Modify the Window class or styles here by modifying
// the CREATESTRUCT cs
return CView::PreCreateWindow(cs);
}
/////////////////////////////////////////////////////////////////////////////
// CFView drawing
void CFView::OnDraw(CDC* pDC)
{
CFDoc* pDoc = GetDocument();
ASSERT_VALID(pDoc);
// TODO: add draw code for native data here
static BOOL bBusy=FALSE;
if(bBusy) return;
bBusy=TRUE;
glClear(GL_COLOR_BUFFER_BIT|GL_DEPTH_BUFFER_BIT);
glMatrixMode(GL_MODELVIEW);
glLoadIdentity();
mydraw();
glFinish();
SwapBuffers(wglGetCurrentDC());
bBusy=FALSE;
}
/////////////////////////////////////////////////////////////////////////////
// CFView printing
BOOL CFView::OnPreparePrinting(CPrintInfo* pInfo)
{
// default preparation
return DoPreparePrinting(pInfo);
}
void CFView::OnBeginPrinting(CDC* /*pDC*/, CPrintInfo* /*pInfo*/)
{
// TODO: add extra initialization before printing
}
void CFView::OnEndPrinting(CDC* /*pDC*/, CPrintInfo* /*pInfo*/)
{
// TODO: add cleanup after printing
}
/////////////////////////////////////////////////////////////////////////////
// CFView diagnostics
#ifdef _DEBUG
void CFView::AssertValid() const
{
CView::AssertValid();
}
void CFView::Dump(CDumpContext& dc) const
{
CView::Dump(dc);
}
CFDoc* CFView::GetDocument() // non-debug version is inline
{
ASSERT(m_pDocument->IsKindOf(RUNTIME_CLASS(CFDoc)));
return (CFDoc*)m_pDocument;
}
#endif //_DEBUG
/////////////////////////////////////////////////////////////////////////////
// CFView message handlers
BOOL CFView::mypixelformat()
{
static PIXELFORMATDESCRIPTOR pfd =
{
sizeof(PIXELFORMATDESCRIPTOR),
1,
PFD_DRAW_TO_WINDOW |
PFD_SUPPORT_OPENGL|// support OpenGL
PFD_DOUBLEBUFFER, // double buffered
PFD_TYPE_RGBA,
24,
0, 0, 0, 0, 0, 0,
0,
0,
0,
0, 0, 0, 0,
32,
0,
0,
PFD_MAIN_PLANE,
0,
0, 0, 0
};
int pixelformat;
if ( (pixelformat = ChoosePixelFormat(my_pDC->GetSafeHdc(), &pfd)) == 0 )
{
MessageBox("ChoosePixelFormat failed");
return FALSE;
}
if (SetPixelFormat(my_pDC->GetSafeHdc(), pixelformat, &pfd) == FALSE)
{
MessageBox("SetPixelFormat failed");
return FALSE;
}
return TRUE;
}
void CFView::myfirst()
{
PIXELFORMATDESCRIPTOR pfd;
int n;
HGLRChrc;
my_pDC = new CClientDC(this);
ASSERT(my_pDC != NULL);
if (!mypixelformat())
return;
n =::GetPixelFormat(my_pDC->GetSafeHdc());
::DescribePixelFormat(my_pDC->GetSafeHdc(), n, sizeof(pfd), &pfd);
hrc = wglCreateContext(my_pDC->GetSafeHdc());
wglMakeCurrent(my_pDC->GetSafeHdc(), hrc);
GetClientRect(&my_oldRect);
glClearDepth(1.0f);
glEnable(GL_DEPTH_TEST);
glMatrixMode(GL_MODELVIEW);
glLoadIdentity();
}
int CFView::OnCreate(LPCREATESTRUCT lpCreateStruct)
{
if (CView::OnCreate(lpCreateStruct) == -1)
return -1;
// TODO: Add your specialized creation code here
myfirst();
return 0;
}
void CFView::OnCancelMode()
{
CView::OnCancelMode();
// TODO: Add your message handler code here
}
void CFView::OnDestroy()
{
CView::OnDestroy();
// TODO: Add your message handler code here
HGLRChrc;
hrc = ::wglGetCurrentContext();
::wglMakeCurrent(NULL, NULL);
if (hrc)
::wglDeleteContext(hrc);
if (my_pDC)
delete my_pDC;
}
void CFView::OnBUTTONnurbs()
{
// TODO: Add your command handler code here
mynurbs=!mynurbs;
glClearColor(0.0f,0.0f,1.0f,1.0f);
Invalidate(FALSE);
}
void CFView::mydraw()
{
glTranslatef(0.0f,0.0f,-6.0f);
if(mybezier) {Mybezier();};
if(mynurbs){Mynurbs();};
}
void CFView::Mynurbs()
{
glPushMatrix();
glBegin(GL_LINES);
glVertex2f(0.0f,0.0f);
glVertex2f(0.01f,-0.4f);
glEnd();
glPopMatrix();
}
[解决办法]
我猜测可能有以下几个方面的问题：
1、线条颜色和背景色重合，所以显示不出来。建议给线条赋予不用的颜色；
2、线条在视景体之外绘制了。建议对视景体进行明确设置，不要使用默认的，特别是前后平面的位置，要将线条的位置囊括在内。
[解决办法]
没看到你设置的近远观察平面，或者说视锥大小，你这个不一定是没画出来，是你画出来了但看不到，所以，要设置一下观察矩阵，而且在画出之前，建议压一下栈，画完弹出
[解决办法]
看看这个可不可以参考一下
http://blog.csdn.net/xianglitian/archive/2011/01/26/6164103.aspx
[解决办法]
倒掉。。您这个视景体完全没有把那根线包含在内，当然看不到了。
您的线的空间实际位置应该是（0,0,-6）（0.01,-0.4,-6）
而您的视景体的x轴范围是是-1~0，您说能看到吗？改成-1~1应该就能看到了
