/////////////////////////////////////////////////////////////////

/// @file Lines.cpp

/// @author Chris L Baker (clb) <chris@chimail.net>

/// @date 2014.05.20

/// @brief Provide a simple interface to draw a line

///

/// @attention Copyright (C) 2014

/// @attention All rights reserved

/////////////////////////////////////////////////////////////////

#include "Lines.h"

#include <osg/Geometry>

#include <osg/Version>

namespace d3

{

/////////////////////////////////////////////////////////////////

/////////////////////////////////////////////////////////////////

osg::ref_ptr<osg::Node> get(const LineVec_t& lines)

{

// define the color array - these are all the colors we need!

osg::ref_ptr<osg::Vec4Array> osgColors( new osg::Vec4Array() );

// here are the lines lto add

osg::ref_ptr<osg::Vec3Array> verts( new osg::Vec3Array() );

// color mapping

osg::ref_ptr<osg::TemplateIndexArray<unsigned int, osg::Array::UIntArrayType, 4, 4> >

colorIndexArray(new osg::TemplateIndexArray<unsigned int, osg::Array::UIntArrayType, 4, 4>());

// the actual line indices

osg::ref_ptr<osg::DrawElementsUInt> theLines( new osg::DrawElementsUInt(osg::PrimitiveSet::LINES, 0) );

// add the lines and colors - only iterate the list once so we know we have

// the right number of lines and colors

unsigned int index(0);

for ( const Line& line : lines )

{

verts->push_back(line.begin);

osgColors->push_back(line.color);

colorIndexArray->push_back(index);

theLines->push_back(index++);

verts->push_back(line.end);

osgColors->push_back(line.color);

colorIndexArray->push_back(index);

theLines->push_back(index++);

}

// now add all this stuff to the geometry object

osg::ref_ptr<osg::Geometry> cloudGeometry( new osg::Geometry() );

cloudGeometry->setVertexArray(verts);

#if OSG_MIN_VERSION_REQUIRED(3,2,0)

cloudGeometry->setColorArray(osgColors, osg::Array::Binding::BIND_PER_VERTEX);

#else // OSG_MIN_VERSION_REQUIRED(3,2,0)

cloudGeometry->setColorArray(osgColors);

cloudGeometry->setColorBinding(osg::Geometry::BIND_PER_VERTEX);

#endif // OSG_MIN_VERSION_REQUIRED(3,2,0)

cloudGeometry->addPrimitiveSet(theLines);

// set the state - line size and lighting

cloudGeometry->getOrCreateStateSet()->setMode(GL_LIGHTING, osg::StateAttribute::OFF);

// create and return the geode

osg::ref_ptr<osg::Geode> geode(new osg::Geode());

geode->addDrawable(cloudGeometry);

return geode;

};

} // namespace d3