[wxWidgets.git] / docs / latex / wx / glcontext.tex

\section{\class{wxGLContext}}\label{wxglcontext}

An instance of a wxGLContext represents the state of an OpenGL state machine and the connection between OpenGL and the system.

The OpenGL state includes everything that can be set with the OpenGL API: colors, rendering variables, display lists, texture objects, etc.
Although it is possible to have multiple rendering contexts share display lists in order to save resources,
this method is hardly used today any more, because display lists are only a tiny fraction of the overall state.

Therefore, one rendering context is usually used with or bound to multiple output windows in turn,
so that the application has access to the \emph{complete and identical} state while rendering into each window.

Binding (making current) a rendering context with another instance of a wxGLCanvas however works only
if the other wxGLCanvas was created with the same attributes as the wxGLCanvas from which the wxGLContext
was initialized. (This applies to sharing display lists among contexts analogously.)

Note that some wxGLContext features are extremely platform-specific - its best to check your native platform's glcanvas header (on windows include/wx/msw/glcanvas.h) to see what features your native platform provides.

\wxheading{Derived from}

\helpref{wxObject}{wxobject}

\wxheading{Include files}

<wx/glcanvas.h>

\wxheading{See also}

\helpref{wxGLCanvas}{wxglcanvas}

\latexignore{\rtfignore{\wxheading{Members}}}


\membersection{wxGLContext::wxGLContext}\label{wxglcontextconstr}

\func{ }{wxGLContext}{ \param{wxGLCanvas*}{ win}, \param{const wxGLContext*}{ other=NULL} }

Constructor.

\docparam{win}{The canvas that is used to initialize this context. This parameter is needed only temporarily,
and the caller may do anything with it (e.g. destroy the window) after the constructor returned.

It will be possible to bind (make current) this context to any other wxGLCanvas that has been created
with equivalent attributes as {\it win}.}

\docparam{other}{Context to share display lists with or NULL (the default) for no sharing.}


\membersection{wxGLContext::SetCurrent}\label{wxglcontextsetcurrent}

\func{void}{SetCurrent}{\param{const wxGLCanvas&}{ win}}

Makes the OpenGL state that is represented by this rendering context current with the wxGLCanvas {\it win}.
Note that {\it win} can be a different wxGLCanvas window than the one that was passed to the constructor of this rendering context.
If { \it RC } is an object of type wxGLContext, the statements { \it RC.SetCurrent(win); } and { \it win.SetCurrent(RC); } are equivalent,
see \helpref{wxGLCanvas::SetCurrent}{wxglcanvassetcurrentrc}.
Commit	Line	Data
38fc80ae RN	1	\section{\class{wxGLContext}}\label{wxglcontext}
38fc80ae RN	2
b7ea712c	3	An instance of a wxGLContext represents the state of an OpenGL state machine and the connection between OpenGL and the system.
38fc80ae	4
b7ea712c RR	5	The OpenGL state includes everything that can be set with the OpenGL API: colors, rendering variables, display lists, texture objects, etc.
	6	Although it is possible to have multiple rendering contexts share display lists in order to save resources,
	7	this method is hardly used today any more, because display lists are only a tiny fraction of the overall state.
38fc80ae	8
b7ea712c RR	9	Therefore, one rendering context is usually used with or bound to multiple output windows in turn,
	10	so that the application has access to the \emph{complete and identical} state while rendering into each window.
	11
	12	Binding (making current) a rendering context with another instance of a wxGLCanvas however works only
	13	if the other wxGLCanvas was created with the same attributes as the wxGLCanvas from which the wxGLContext
	14	was initialized. (This applies to sharing display lists among contexts analogously.)
38fc80ae RN	15
	16	Note that some wxGLContext features are extremely platform-specific - its best to check your native platform's glcanvas header (on windows include/wx/msw/glcanvas.h) to see what features your native platform provides.
	17
	18	\wxheading{Derived from}
	19
	20	\helpref{wxObject}{wxobject}
	21
	22	\wxheading{Include files}
	23
f2ac0386 RN	24	<wx/glcanvas.h>
	25
	26	\wxheading{See also}
38fc80ae RN	27
	28	\helpref{wxGLCanvas}{wxglcanvas}
	29
	30	\latexignore{\rtfignore{\wxheading{Members}}}
	31
38fc80ae	32
b7ea712c	33	\membersection{wxGLContext::wxGLContext}\label{wxglcontextconstr}
38fc80ae	34
b7ea712c	35	\func{ }{wxGLContext}{ \param{wxGLCanvas}{ win}, \param{const wxGLContext}{ other=NULL} }
38fc80ae	36
b7ea712c	37	Constructor.
38fc80ae	38
b7ea712c RR	39	\docparam{win}{The canvas that is used to initialize this context. This parameter is needed only temporarily,
b7ea712c RR	40	and the caller may do anything with it (e.g. destroy the window) after the constructor returned.
38fc80ae	41
b7ea712c RR	42	It will be possible to bind (make current) this context to any other wxGLCanvas that has been created
b7ea712c RR	43	with equivalent attributes as {\it win}.}
38fc80ae	44
b7ea712c	45	\docparam{other}{Context to share display lists with or NULL (the default) for no sharing.}
38fc80ae	46
38fc80ae RN	47
	48	\membersection{wxGLContext::SetCurrent}\label{wxglcontextsetcurrent}
	49
b7ea712c	50	\func{void}{SetCurrent}{\param{const wxGLCanvas&}{ win}}
058a62b1	51
b7ea712c RR	52	Makes the OpenGL state that is represented by this rendering context current with the wxGLCanvas {\it win}.
	53	Note that {\it win} can be a different wxGLCanvas window than the one that was passed to the constructor of this rendering context.
	54	If { \it RC } is an object of type wxGLContext, the statements { \it RC.SetCurrent(win); } and { \it win.SetCurrent(RC); } are equivalent,
418ab1e7	55	see \helpref{wxGLCanvas::SetCurrent}{wxglcanvassetcurrentrc}.