eglSwapBuffers example c c++ java

Name

eglSwapBuffers - post EGL surface color buffer to a native window

C Specification

EGLBoolean eglSwapBuffers(EGLDisplay display,
    EGLSurface surface)

Parameters

display

Specifies the EGL display connection.

surface

Specifies the EGL drawing surface whose buffers are to be swapped.

Description

If surface is a window surface, eglSwapBuffers posts its color buffer to the associated native window.
eglSwapBuffers performs an implicit glFlush before it returns. Subsequent GL commands may be issued immediately after calling eglSwapBuffers, but are not executed until the buffer exchange is completed.
If surface is a pixel buffer or a pixmap, eglSwapBuffers has no effect, and no error is generated.

Notes

The color buffer of surface is left undefined after calling eglSwapBuffers.

Errors

EGL_FALSE is returned if swapping of the surface buffers fails, EGL_TRUE otherwise.
EGL_BAD_DISPLAY is generated if display is not an EGL display connection.
EGL_NOT_INITIALIZED is generated if display has not been initialized.
EGL_BAD_SURFACE is generated if surface is not an EGL drawing surface.

Copyright

Copyright © 2003 Silicon Graphics, Inc.
This document is licensed under the SGI Free Software B License. For details, see http://oss.sgi.com/projects/FreeB/.

See Also

glFlush, eglCopyBuffers

Example of eglswapbuffers

void CXXXView::OnInitialUpdate()

{

 CView::OnInitialUpdate();

 // TODO: Add your specialized code here and/or call the base class

 if (m_eglDisplay != EGL_NO_DISPLAY)

  return;

 const EGLint attrs[] = {

  EGL_LEVEL, 0,

  EGL_SURFACE_TYPE, EGL_WINDOW_BIT,

  EGL_RENDERABLE_TYPE, EGL_OPENGL_ES2_BIT,

  EGL_NATIVE_RENDERABLE, EGL_FALSE,

  EGL_DEPTH_SIZE, EGL_DONT_CARE,

  EGL_NONE

 };

 EGLint numConfig =0;

 m_eglDisplay = eglGetDisplay(GetDC()->GetSafeHdc());

 if (m_eglDisplay == EGL_NO_DISPLAY)

  if ((m_eglDisplay = eglGetDisplay((EGLNativeDisplayType) EGL_DEFAULT_DISPLAY)) == EGL_NO_DISPLAY)

   return;

 // Initialize the display

 EGLint major = 0;

 EGLint minor = 0;

 if (!eglInitialize(m_eglDisplay, &major, &minor))

  return;

 if (major < 1 || minor < 3)

 {

  // Does not support EGL 1.3

  printf("System does not support at least EGL 1.3 \n");

  return;

 }

 EGLConfig eglConfig;

 // Obtain the first configuration with a depth buffer

 if (!eglChooseConfig(m_eglDisplay, attrs, &eglConfig, 1, &numConfig))

  return;

 // Create a surface for the main window

 if ((m_eglSurface = eglCreateWindowSurface(m_eglDisplay, eglConfig, (EGLNativeWindowType) GetSafeHwnd(), NULL)) == EGL_NO_SURFACE)

  return;

 // Bind the API (It could be OpenGLES or OpenVG)

 // eglBindAPI(EGL_OPENGL_ES_API);

 EGLint ai32ContextAttribs[] = { EGL_CONTEXT_CLIENT_VERSION, 2, EGL_NONE };

 // Create an OpenGL ES context

 if ((m_eglContext = eglCreateContext(m_eglDisplay, eglConfig, EGL_NO_CONTEXT, ai32ContextAttribs)) == EGL_NO_CONTEXT)

  return;

 // Make the context and surface current

 if (!eglMakeCurrent(m_eglDisplay, m_eglSurface, m_eglSurface, m_eglContext))

  return;

 ///

 glClearColor(0.5f, 0.5f, 0.5f, 0.0f);

}

void CXXXView::PostNcDestroy()

{

 // TODO: Add your specialized code here and/or call the base class

 eglMakeCurrent(EGL_NO_DISPLAY, EGL_NO_SURFACE, EGL_NO_SURFACE, EGL_NO_CONTEXT);

 eglDestroyContext(m_eglDisplay, m_eglContext);

 eglDestroySurface(m_eglDisplay, m_eglSurface);

 eglTerminate(m_eglDisplay);

 CView::PostNcDestroy();

}

void CXXXView::onDraw(void)

{

 glClear(GL_COLOR_BUFFER_BIT);

 ///

 IGameImporter * gameImport = NULL;

 auto pDoc = GetDocument();

 if (pDoc && pDoc->IsKindOf(RUNTIME_CLASS(CXXXDoc)))

  gameImport = dynamic_cast<cxxxdoc *=""> (pDoc)->getGameImport();

 ///

 eglSwapBuffers(m_eglDisplay, m_eglSurface);

}

BOOL CXXXView::OnEraseBkgnd(CDC* pDC)

{

 // TODO: Add your message handler code here and/or call default

 /// return CView::OnEraseBkgnd(pDC);

 return FALSE;

}

void CXXXView::OnSize(UINT nType, int cx, int cy)

{

 CView::OnSize(nType, cx, cy);

 // TODO: Add your message handler code here

 glViewport(0, 0, cx, cy);

}

/// CXXXApp.cpp

BOOL CXXXApp::OnIdle(LONG lCount)

{

 // TODO: Add your specialized code here and/or call the base class

// return CWinAppEx::OnIdle(lCount);

 CMainFrame * pFrame = (CMainFrame *) AfxGetMainWnd();

 CView * pView = pFrame->GetActiveView();

 if (pView && pView->IsKindOf(RUNTIME_CLASS(CXXXView)))

  dynamic_cast<cxxxview *=""> (pView)->onDraw();

 return TRUE;

}

/// CViewTree.h

#define WM_TVN_SELCHANGED (WM_USER+3)

class CViewTree : public CTreeCtrl

{

public:

 afx_msg void OnTvnSelchanged(NMHDR *pNMHDR, LRESULT *pResult);

};

/// CViewTree.cpp

BEGIN_MESSAGE_MAP(CViewTree, CTreeCtrl)

 ON_NOTIFY_REFLECT(TVN_SELCHANGED, &CViewTree::OnTvnSelchanged)

END_MESSAGE_MAP()

void CViewTree::OnTvnSelchanged(NMHDR *pNMHDR, LRESULT *pResult)

{

 LPNMTREEVIEW pNMTreeView = reinterpret_cast<lpnmtreeview>(pNMHDR);

 // TODO: Add your control notification handler code here

 GetParent()->SendNotifyMessage(WM_TVN_SELCHANGED, (WPARAM) pNMTreeView, (LPARAM) pResult);

 *pResult = 0;

}