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#ifndef _CWGL_H_
#define _CWGL_H_
#define WGL_DONT_SWAP_BUFFERS true
#define WGL_FONTS_LISTBASE 1000
// define group
/*!
\defgroup OGLToolsGroup OGLTools Library : OpenGL Tools for MFC
*/
/*! \brief A Windows OpenGL rendering interface class.
\ingroup OGLToolsGroup
CWGL is a Windows OpenGL rendering interface class.
This header defines also a few interfaceing wgl_ inlines.
The idea behing the CWGL is to make use
of OpenGL in Microsoft Windows as simple as possible.
Under Windows only one OpenGL rendering context may be active
in a single thread. CWGL helps you write a single threaded
windows applications which need more than one OpenGL
rendering context.
\b Usage:
<ol>
<il> Optionaly, set different pixelformat if you are
not satisfied with CWGL's default one.
<li> Enable OpenGL telling it where it should render.
\code wgl.Begin(&windowOrBitmapDC); \endcode
<li> Call OpenGL API functions to do the rendering.
<li> Disable OpenGL, first optionaly showing the rendered image.
\code wgl.End(); \endcode
</ol>
\b Examples:
In MFC view, render to window's backbuffer and swap buffers.
\code
CView.h
CWGL m_wgl;
CView.cpp
CView::OnDraw(pDC)
{
m_wgl.Begin(pDC);
glClearColor(1.0, 1.0, 1.0, 0.0);
glClear(GL_COLOR_BUFFER_BIT);
m_wgl.End();
}
\endcode
Render on DIB section GDI object and copy it to clipboard.
\code
CRGBSurface tmpSurf; // CRGBSurface encapsulates a DIB section GDI object
tmpSurf.Create(10, 10);
CWGL wgl;
wgl.Begin(tmpSurf.GetDC());
glClearColor(1.0, 1.0, 1.0, 0.0)
glClear(GL_COLOR_BUFFER_BIT);
wgl.End();
tmpSurf.CopyToClipboard();
\endcode
Rendering contexts may be 'nested' if different
CWGL objects are used,
but remember that only one RC can be created for one window.
\code
wgl1.Begin(&windowDC);
{
CWGL wgl2;
wgl2.Begin(&bitmapDC);
wgl2.End();
// here wgl2 destructor delete's wgl2 RC and makes
// wgl1 RC current again.
}
// here all the display lists and textures of wgl1 RC
// remain valid
wgl1.End();
\endcode
If you need an RC for a window for which you
no longer have a device context available,
you may call wgl.Begin() with no DC
to make last used RC of this window current again.
\code
wgl.Begin(&windowDC);
wgl.End();
...
// some time in the future...
wgl.Begin();
wgl.End();
\endcode
After a call to CWGL::End() you may ask what the
rendering time was with GetRenderingTime().
NOTES:
When rendering on different DIB sections or bitmaps, a new RC with
PFD_DRAW_TO_BITMAP pixelformat is always created for that bitmap.
WindowsNT: CWGL synchronizes GDI and OpenGL access to
rendering surface automaticaly.
When switching RC's of different pixelformats with CWGL,
all textures and display lists must be recreated in a new RC.
Display list sharing is possible when RCs are of the same pixelformat
(this means also that you cannot share between window and bitmap RC).
Please also note that under Windows only one RC
may be created for a given window and this RC cannot be
used for another window.
\sa CGLImage
\sa CRGBSurface
\author (c) W.Weyna 'Voytec', http://shiptech.tuniv.szczecin.pl/~weyna/OpenGL/
\author Independent JPEG library : http://www.ijg.org
*/
class CWGL
{
public:
//! Default constructor.
CWGL();
//! Default destructor. Destroy all.
virtual ~CWGL();
// Attributes
public:
/*! \name Attributes */
//@{
//! TRUE if a new RC has been created.
bool NewRCCreated() {return m_bNewRCCreated; }
//! Rendering time
DWORD GetRenderingTime() {return m_dwRenderingTime; }
//! Pointer to DC
CDC* GetRenderingDC() {return m_pDC; }
//! true if rendering to bitmap.
bool RenderingToBitmap() {return m_pDC ? false : true;}
//! true if full screen mode
bool IsFullScreen() {return m_bFullScreen; }
//! returns window width (in pixels)
int GetFSWidth() {return m_windowRect.Width(); }
//! returns window height (in pixels)
int GetFSHeight() {return m_windowRect.Height(); }
//@}
protected:
CDC* m_pDC;
CDC* m_pBitmapDC;
CWnd* m_pWnd;
HWND m_hWnd;
HGLRC m_hWndRC;
HGLRC m_hFSWndRC;
HGLRC m_hBmpRC;
HDC m_hPrevDC;
HGLRC m_hPrevRC;
bool m_bNewRCCreated;
bool m_bWeCreatedDC;
DWORD m_dwRenderingTime;
DWORD m_dwStartRenderingTime;
LOGFONT m_defaultLogfont;
CFont m_defaultFont;
LOGFONT m_currentLogfont;
CFont m_currentFont;
CFont* m_pFont;
HWND m_hFSWnd;
HWND m_hViewWnd;
CView* m_pView;
bool m_bFullScreen;
int m_nMode;
CRect m_windowRect;
// Operations
public:
/*! \name Operations: */
//@{
/*! \brief Enables OpenGL.
It enables OpenGL and makes all subsequent OpenGL calls
render on a surface associated with supplied DC.
After all OpenGL calls have been made,
CWGL::End() must be called.
Any OpenGL calls made before a call to CWGL::Begin()
have no effect.
\sa CWGL::End
*/
bool Begin(CDC* pDC = NULL);
/*! \brief End OpenGL
Finish rendering and if rendered to double-buffered window,
show the rendered image.
Release currently selected RC.
After a call to this function is made, any subsequent
OpenGL calls will have no effect.
\sa CWGL::Begin
*/
void End(bool m_bDontSwapBuffers = false);
/*! \brief Toggle full screen on/off
Call this function to toggle full screen mode.
This function will also subclass the created full screen window
if a pointer to a CView derived view is passed.
See switch statement for description of nMode parameter.
*/
bool FullScreen(int nMode = -1, CView* pView = NULL);
/*! \brief Draw string str at raster position.
\sa CWGL::CompileFonts
*/
void TextOut(const CString& str);
//@}
// Helpers
public:
/*! \name Helpers */
//@{
/*! \brief Time helper.
This fuction returns a time difference in miliseconds
between the current time and dwStartTime obtained
with GetTickCount(). It works also when tick counter will
reset which happens after every 49.5 days.
*/
DWORD GetTimeDif(DWORD dwStartTime);
//@}
protected:
/*! \brief Sets the pixel format.
Set pixelformat, default is 24bit RGB double-buffered window.
If you want to work with different pixelformats,
add appropriate methods by yourself.
*/
bool SetPixelFormat(CDC* pDC, DWORD dwFlags =
PFD_DRAW_TO_WINDOW | PFD_DOUBLEBUFFER,
int nBitsPerPixel = 24);
/*! \brief Compile font lists.
\sa CWGL::TextOut
*/
void CompileFonts();
};
inline BYTE GetAValue(DWORD rgb) { return (BYTE)((rgb)>>24); }
inline void wgl_ClearColorCR(COLORREF cr, float fAlpha = 1.0)
{
glClearColor(GetRValue(cr)/255.0f, GetGValue(cr)/255.0f, GetBValue(cr)/255.0f, fAlpha);
}
inline void wgl_ColorCR(COLORREF cr, float fAlpha = 1.0, float fBrightness = 1.0)
{
glColor4f(fBrightness * GetRValue(cr)/255.0f, fBrightness * GetGValue(cr)/255.0f, fBrightness * GetBValue(cr)/255.0f, fAlpha);
}
inline void wgl_ColorCRA(COLORREF cr)
{
glColor4f(GetRValue(cr)/255.0f, GetGValue(cr)/255.0f, GetBValue(cr)/255.0f, GetAValue(cr)/255.0f);
}
inline void wgl_ColorCRB(COLORREF cr, float fAlpha = 1.0, int nBrightness = 0)
{
float fBrightness = 1.0;
switch(nBrightness)
{
case 0:
fBrightness = 1.0;
break;
case 1:
fBrightness = 0.85f;
break;
case 2:
fBrightness = 1.15f;
break;
}
glColor4f(fBrightness * GetRValue(cr)/255.0f, fBrightness * GetGValue(cr)/255.0f, fBrightness * GetBValue(cr)/255.0f, fAlpha);
}
#ifdef _DEBUG
inline bool wgl_ErrorCheck()
{
GLenum errCode;
if((errCode = glGetError()) != GL_NO_ERROR)
{
AfxMessageBox((TCHAR*)gluErrorString(errCode));
ASSERT(0);
return false;
}
return true;
}
#else
inline bool wgl_ErrorCheck() {return glGetError() == GL_NO_ERROR; }
#endif
#endif
//////////////////////////////////////////////////////////////////////
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I started programming on 8 bit machines as a teenager, writing my first compiled programming language before I was 16. I went on to study Engineering and Computer Science at Oxford University, getting a first and the University Prize for the best results in Computer Science. Since then I have worked in a variety of roles, involving systems management and development management on a wide variety of platforms. Now I manage a software development company producing CAD software for Windows using C++.
My 3 favourite reference books are: Design Patterns, Gamma et al; The C++ Standard Library, Josuttis; and Computer Graphics, Foley et al.
Outside computers, I am also the drummer in a band, The Unbelievers and we have just released our first album. I am a pretty good juggler and close up magician, and in my more insane past, I have cycled from Spain to Eastern Turkey, and cycled across the Namib desert.