/// <summary>
/// Query the version of the current OpenGL context.
/// </summary>
/// <returns>
/// It returns the <see cref="KhronosVersion"/> specifying teh actual version of <paramref name="ctx"/>.
/// </returns>
internal static KhronosVersion QueryContextVersion()
{
IntPtr ctx = GetCurrentContext();
if (ctx == null)
{
throw new InvalidOperationException("no current context");
}
// Load minimal Gl functions for querying information
IGetProcAddress getProcAddress = GetProcAddress.GetProcAddressGL;
if (Egl.IsRequired == false)
{
Gl.BindAPIFunction(Gl.Version_100, "glGetError", getProcAddress);
Gl.BindAPIFunction(Gl.Version_100, "glGetString", getProcAddress);
}
else
{
Gl.BindAPIFunction(Gl.Version_320_ES, "glGetError", getProcAddress);
Gl.BindAPIFunction(Gl.Version_320_ES, "glGetString", getProcAddress);
}
// Parse version string (effective for detecting Desktop and ES contextes)
KhronosVersion glversion = KhronosVersion.Parse(Gl.GetString(StringName.Version));
// ATM do not support fancy context creation flags
return(glversion);
}
/// <summary>
/// Query the version of the current OpenGL context.
/// </summary>
/// <returns>
/// It returns the <see cref="KhronosVersion"/> specifying teh actual version of <paramref name="ctx"/>.
/// </returns>
private static KhronosVersion QueryContextVersion()
{
IntPtr ctx = DeviceContext.GetCurrentContext();
if (ctx == null)
{
throw new InvalidOperationException("no current context");
}
// Load minimal Gl functions for querying information
IGetProcAddress getProcAddress = GetProcAddress.GetProcAddressGL;
if (Egl.IsRequired == false)
{
Gl.BindAPIFunction(Gl.Version_100, null, "glGetError", getProcAddress);
Gl.BindAPIFunction(Gl.Version_100, null, "glGetString", getProcAddress);
Gl.BindAPIFunction(Gl.Version_100, null, "glGetIntegerv", getProcAddress);
}
else
{
Gl.BindAPIFunction(Gl.Version_320_ES, null, "glGetError", getProcAddress);
Gl.BindAPIFunction(Gl.Version_320_ES, null, "glGetString", getProcAddress);
Gl.BindAPIFunction(Gl.Version_320_ES, null, "glGetIntegerv", getProcAddress);
}
// Parse version string (effective for detecting Desktop and ES contextes)
KhronosVersion glversion = KhronosVersion.Parse(Gl.GetString(StringName.Version));
// Context profile
if (glversion.Api == KhronosVersion.ApiGl && glversion >= Gl.Version_320)
{
string glProfile = null;
int ctxProfile = 0;
Gl.Get(Gl.CONTEXT_PROFILE_MASK, out ctxProfile);
if ((ctxProfile & Gl.CONTEXT_COMPATIBILITY_PROFILE_BIT) != 0)
{
glProfile = KhronosVersion.ProfileCompatibility;
}
else if ((ctxProfile & Gl.CONTEXT_CORE_PROFILE_BIT) != 0)
{
glProfile = KhronosVersion.ProfileCore;
}
else
{
glProfile = KhronosVersion.ProfileCompatibility;
}
return(new KhronosVersion(glversion, glProfile));
}
else
{
return(new KhronosVersion(glversion, KhronosVersion.ProfileCompatibility));
}
}
