ScreenGLProc
Gets the address of an OpenGL procedure
Syntax
`
Declare Function ScreenGLProc ( ByRef procname As Const String ) As Any Ptr
`
Parameters
`procname`
name of the procedure to retrieve the address of
Description
This function can be used to get the address of any OpenGL procedure, to be used to retrieve the pointers to new functions associated with OpenGL extensions. If given procedure named `procname` cannot be found, `ScreenGLProc` will return NULL (0).
Example
`
'' include fbgfx.bi for some useful definitions
#include "fbgfx.bi"
Dim SwapInterval As Function(ByVal interval As Integer) As Integer
Dim extensions As String
'' Setup OpenGL and retrieve supported extensions
ScreenRes 640, 480, 32,, FB.GFX_OPENGL
ScreenControl FB.GET_GL_EXTENSIONS, extensions
If (InStr(extensions, "WGL_EXT_swap_control") <> 0) Then
'' extension supported, retrieve proc address
SwapInterval = ScreenGLProc("wglSwapIntervalEXT")
If (SwapInterval <> 0) Then
'' Ok, we got it. Set OpenGL to wait for vertical sync on buffer swaps
SwapInterval(1)
End If
End If
`
Dialect Differences

- Not available in the -lang qb dialect unless referenced with the alias `__Screenglproc`.

Platform Differences

- Not available for DOS target.

Differences from QB

- New to FreeBASIC

See also

- `Screen (Graphics)`
- `ScreenControl`