/**************************************************************************\
 * Copyright (c) Kongsberg Oil & Gas Technologies AS
 * All rights reserved.
 * 
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are
 * met:
 * 
 * Redistributions of source code must retain the above copyright notice,
 * this list of conditions and the following disclaimer.
 * 
 * Redistributions in binary form must reproduce the above copyright
 * notice, this list of conditions and the following disclaimer in the
 * documentation and/or other materials provided with the distribution.
 * 
 * Neither the name of the copyright holder nor the names of its
 * contributors may be used to endorse or promote products derived from
 * this software without specific prior written permission.
 * 
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
\**************************************************************************/

/*!
  \class SoGLColorIndexElement Inventor/elements/SoGLColorIndexElement.h
  \brief The SoGLColorIndexElement class sets the current OpenGL color.

  \ingroup elements

  This element is only used when the OpenGL canvas is in colorindex
  mode, ie where colors for individual pixels are fetched from a color
  lookup table ("CLUT"). The usual thing to do is to set up a canvas
  in RGBA truecolor mode.

  One common use for colorindex mode OpenGL canvases is to use one in
  the overlay planes (which are usually limited to only 2 or 4
  available colors), if supported by the OpenGL hardware and / or
  driver.

  \sa SoColorIndex
*/

#include <Inventor/elements/SoGLColorIndexElement.h>
#include <Inventor/elements/SoGLLazyElement.h>
#include <Inventor/misc/SoState.h>
#include <cassert>

#ifdef HAVE_CONFIG_H
#include <config.h>
#endif // HAVE_CONFIG_H

#include <Inventor/system/gl.h>

SO_ELEMENT_SOURCE(SoGLColorIndexElement);

// doc in parent
void
SoGLColorIndexElement::initClass(void)
{
  SO_ELEMENT_INIT_CLASS(SoGLColorIndexElement, inherited);
}


// doc in parent
void
SoGLColorIndexElement::init(SoState * stateptr)
{
  inherited::init(state);
  this->state = stateptr;
}

/*!
  The destructor.
*/
SoGLColorIndexElement::~SoGLColorIndexElement()
{
}

/*!
  Returns \c TRUE if the current GL context is in color index mode.
*/
SbBool
SoGLColorIndexElement::isColorIndexMode(SoState * state)
{
  return SoGLLazyElement::isColorIndex(state);
}

/*!
  Sets current color indices.
*/
void
SoGLColorIndexElement::set(SoState * const state, SoNode * const node,
                           const int32_t numindices,
                           const int32_t * const indices)
{
  SoLazyElement::setColorIndices(state, node, numindices, indices);
}

/*!
  Returns number of color indices in element.
*/
int32_t
SoGLColorIndexElement::getNum(void) const
{
  return SoLazyElement::getInstance(this->state)->getNumColorIndices();
}

/*!
  Returns the current element.
*/
const SoGLColorIndexElement *
SoGLColorIndexElement::getInstance(SoState *state)
{
  return (const SoGLColorIndexElement *)
    state->getElementNoPush(classStackIndex);
}

int32_t
SoGLColorIndexElement::get(const int index) const
{
  assert(index >= 0 && index < this->getNum());
  return SoLazyElement::getColorIndices(this->state)[index];
}

int32_t
SoGLColorIndexElement::getDefault(void)
{
  return SoLazyElement::getDefaultColorIndex();
}
