OpenSceneGraph/src/osg/BlendEquation.cpp
Robert Osfield 409cdd0b28 Intoduced a new setGLExtensions template method to do a copy of void* pointer to
local function pointer to avoid compiler warnings related to case void*.

Moved various OSG classes across to using setGLExtensions instead of getGLExtensions,
and changed them to use typedef declarations in the headers rather than casts in
the .cpp.

Updated wrappers
2007-09-10 15:19:23 +00:00

130 lines
3.9 KiB
C++

/* -*-c++-*- OpenSceneGraph - Copyright (C) 1998-2006 Robert Osfield
*
* This library is open source and may be redistributed and/or modified under
* the terms of the OpenSceneGraph Public License (OSGPL) version 0.0 or
* (at your option) any later version. The full license is in LICENSE file
* included with this distribution, and on the openscenegraph.org website.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* OpenSceneGraph Public License for more details.
*/
#include <osg/BlendEquation>
#include <osg/GLExtensions>
#include <osg/State>
#include <osg/Notify>
#include <osg/buffered_value>
using namespace osg;
BlendEquation::BlendEquation():
_equation(FUNC_ADD)
{
}
BlendEquation::BlendEquation(Equation equation):
_equation(equation)
{
}
BlendEquation::~BlendEquation()
{
}
void BlendEquation::apply(State& state) const
{
// get the contextID (user defined ID of 0 upwards) for the
// current OpenGL context.
const unsigned int contextID = state.getContextID();
const Extensions* extensions = getExtensions(contextID,true);
if (!extensions->isBlendEquationSupported())
{
notify(WARN)<<"Warning: BlendEquation::apply(..) failed, BlendEquation is not support by OpenGL driver."<<std::endl;
return;
}
GLenum eqn = static_cast<GLenum>(_equation);
if((eqn == ALPHA_MIN || eqn == ALPHA_MAX) &&
!extensions->isSGIXMinMaxSupported())
{
notify(WARN)<<"Warning: BlendEquation::apply(..) failed, SGIX_blend_alpha_minmax extension is not supported by OpenGL driver." << std::endl;
return;
}
if(eqn == LOGIC_OP && !extensions->isLogicOpSupported())
{
notify(WARN)<<"Warning: BlendEquation::apply(..) failed, EXT_blend_logic_op extension is not supported by OpenGL driver." << std::endl;
return;
}
extensions->glBlendEquation(static_cast<GLenum>(_equation));
}
typedef buffered_value< ref_ptr<BlendEquation::Extensions> > BufferedExtensions;
static BufferedExtensions s_extensions;
BlendEquation::Extensions* BlendEquation::getExtensions(unsigned int contextID,bool createIfNotInitalized)
{
if (!s_extensions[contextID] && createIfNotInitalized) s_extensions[contextID] = new Extensions(contextID);
return s_extensions[contextID].get();
}
void BlendEquation::setExtensions(unsigned int contextID,Extensions* extensions)
{
s_extensions[contextID] = extensions;
}
BlendEquation::Extensions::Extensions(unsigned int contextID)
{
setupGLExtensions(contextID);
}
BlendEquation::Extensions::Extensions(const Extensions& rhs):
Referenced()
{
_isBlendEquationSupported = rhs._isBlendEquationSupported;
_isSGIXMinMaxSupported = rhs._isSGIXMinMaxSupported;
_isLogicOpSupported = rhs._isLogicOpSupported;
_glBlendEquation = rhs._glBlendEquation;
}
void BlendEquation::Extensions::lowestCommonDenominator(const Extensions& rhs)
{
if (!rhs._isBlendEquationSupported) _isBlendEquationSupported = false;
if (!rhs._glBlendEquation) _glBlendEquation = 0;
}
void BlendEquation::Extensions::setupGLExtensions(unsigned int contextID)
{
_isBlendEquationSupported = isGLExtensionSupported(contextID,"GL_EXT_blend_equation") ||
strncmp((const char*)glGetString(GL_VERSION),"1.2",3)>=0;
_isSGIXMinMaxSupported = isGLExtensionSupported(contextID, "GL_SGIX_blend_alpha_minmax");
_isLogicOpSupported = isGLExtensionSupported(contextID, "GL_EXT_blend_logic_op");
setGLExtensionFuncPtr(_glBlendEquation, "glBlendEquation", "glBlendEquationEXT");
}
void BlendEquation::Extensions::glBlendEquation(GLenum mode) const
{
if (_glBlendEquation)
{
_glBlendEquation(mode);
}
else
{
notify(WARN)<<"Error: glBlendEquation not supported by OpenGL driver"<<std::endl;
}
}