NAME

       wxGLCanvas - Functions for wxGLCanvas class

DESCRIPTION

       wxGLCanvas  is  a class for displaying OpenGL graphics. It is always used in conjunction with wxGLContext
       as the context can only be made current (i.e. active for the OpenGL commands) when it is associated to  a
       wxGLCanvas.

       More precisely, you first need to create a wxGLCanvas window and then create an instance of a wxGLContext
       that  is initialized with this wxGLCanvas and then later use either setCurrent/2 with the instance of the
       wxGLContext or wxGLContext:setCurrent/2 with the instance of the wxGLCanvas (which might be not the  same
       as  was  used  for  the  creation  of  the  context)  to bind the OpenGL state that is represented by the
       rendering context to the canvas, and then finally call swapBuffers/1 to swap the buffers  of  the  OpenGL
       canvas and thus show your current output.

       Please  note  that  wxGLContext  always  uses  physical pixels, even on the platforms where wxWindow uses
       logical pixels, affected by the coordinate scaling, on high DPI displays. Thus, if you want  to  set  the
       OpenGL   view   port   to  the  size  of  entire  window,  you  must  multiply  the  result  returned  by
       wxWindow:getClientSize/1 by wxWindow:getContentScaleFactor/1 before  passing  it  to  glViewport().  Same
       considerations  apply  to  other  OpenGL  functions  and  other coordinates, notably those retrieved from
       wxMouseEvent in the event handlers.

       Notice that versions of wxWidgets previous  to  2.9  used  to  implicitly  create  a  wxGLContext  inside
       wxGLCanvas  itself.  This  is  still  supported  in the current version but is deprecated now and will be
       removed in the future, please update your code to create the rendering contexts explicitly.

       To set up the attributes for the canvas (number of bits for the depth buffer,  number  of  bits  for  the
       stencil buffer and so on) you pass them in the constructor using a wxGLAttributes (not implemented in wx)
       instance.  You  can  still  use  the  way  before  3.1.0 (setting up the correct values of the attribList
       parameter) but it's discouraged.

       Note: On those platforms which  use  a  configure  script  (e.g.  Linux  and  macOS)  OpenGL  support  is
       automatically  enabled  if  the relative headers and libraries are found. To switch it on under the other
       platforms (e.g. Windows), you need to edit the setup.h file and set wxUSE_GLCANVAS to  1  and  then  also
       pass  USE_OPENGL=1  to  the  make  utility.  You may also need to add opengl32.lib (and glu32.lib for old
       OpenGL versions) to the list of the libraries your program is linked with.

       See: wxGLContext, wxGLAttributes (not implemented in wx), wxGLContextAttrs (not implemented in wx)

       This class is derived (and can use functions) from: wxWindow wxEvtHandler

       wxWidgets docs: wxGLCanvas

DATA TYPES

       wxGLCanvas() = wx:wx_object()

EXPORTS

       new(Parent) -> wxGLCanvas()

              Types:

                 Parent = wxWindow:wxWindow()

       new(Parent, Options :: [Option]) -> wxGLCanvas()

              Types:

                 Parent = wxWindow:wxWindow()
                 Option =
                     {id, integer()} |
                     {attribList, [integer()]} |
                     {pos, {X :: integer(), Y :: integer()}} |
                     {size, {W :: integer(), H :: integer()}} |
                     {style, integer()} |
                     {name, unicode:chardata()} |
                     {palette, wxPalette:wxPalette()}

              This constructor is still available only for compatibility reasons.

              Please use the constructor with wxGLAttributes (not implemented in wx) instead.

              If attribList is not specified, wxGLAttributes::PlatformDefaults()  (not  implemented  in  wx)  is
              used, plus some other attributes (see below).

       setCurrent(This, Context) -> boolean()

              Types:

                 This = wxGLCanvas()
                 Context = wxGLContext:wxGLContext()

              Makes the OpenGL state that is represented by the OpenGL rendering context context current, i.e.

              it will be used by all subsequent OpenGL calls.

              This is equivalent to wxGLContext:setCurrent/2 called with this window as parameter.

              Note:  This function may only be called when the window is shown on screen, in particular it can't
              usually be called from the constructor as the window isn't yet shown at this moment.

              Return: false if an error occurred.

       createSurface(This) -> boolean()

              Types:

                 This = wxGLCanvas()

       isDisplaySupported(AttribList) -> boolean()

              Types:

                 AttribList = [integer()]

              Determines if a canvas having the specified attributes is available.

              This only applies for visual attributes, not rendering context attributes.  Please,  use  the  new
              form of this method, using wxGLAttributes (not implemented in wx).

              Return: true if attributes are supported.

       swapBuffers(This) -> boolean()

              Types:

                 This = wxGLCanvas()

              Swaps the double-buffer of this window, making the back-buffer the front-buffer and vice versa, so
              that the output of the previous OpenGL commands is displayed on the window.

              Return: false if an error occurred.

       destroy(This :: wxGLCanvas()) -> ok

              Destroys the object.

wxWidgets team.                                    wx 2.2.2.1                                   wxGLCanvas(3erl)