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

/// @file Capsules.cpp

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

/// @date 2014.06.10

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

///

/// @attention Copyright (C) 2014

/// @attention All rights reserved

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

#include "Capsules.h"

#include <osg/ShapeDrawable>

#include <osg/Material>

#include <osg/Geode>

namespace d3

{

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

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

osg::ref_ptr<osg::Node> get(const CapsuleVec_t& capsules)

{

osg::ref_ptr<osg::Group> pAddToThisGroup(new osg::Group());

for ( const auto& cc : capsules )

{

osg::Vec3d pp( cc.begin - cc.end );

double height( pp.length() );

if ( height < 0.000001 ) continue;

osg::Vec3d center( (cc.begin.x() + cc.end.x())/2.0,

(cc.begin.y() + cc.end.y())/2.0,

(cc.begin.z() + cc.end.z())/2.0 );

// This is the default direction for the capsules to face in OpenGL

static const osg::Vec3d ZZ( 0,0,1 );

// Get CROSS product (the axis of rotation)

osg::Vec3d tt( ZZ^pp );

// Get angle. length is magnitude of the vector

double angle( acos( (ZZ * pp) / height) );

// Create a capsule between the two points with the given radius

osg::ref_ptr<osg::Capsule> capsule( new osg::Capsule(center, cc.radius, height) );

capsule->setRotation(osg::Quat(angle, osg::Vec3d(tt.x(), tt.y(), tt.z())));

// A geode to hold the capsule

osg::ref_ptr<osg::ShapeDrawable> capsuleDrawable( new osg::ShapeDrawable(capsule) );

capsuleDrawable->setColor(cc.color);

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

geode->addDrawable(capsuleDrawable);

// Set the color of the capsule that extends between the two points.

// osg::ref_ptr<osg::Material> pMaterial( new osg::Material() );

// pMaterial->setDiffuse( osg::Material::FRONT, cc.color);

// geode->getOrCreateStateSet()->setAttribute( pMaterial, osg::StateAttribute::OVERRIDE );

geode->getOrCreateStateSet()->setMode(GL_BLEND, osg::StateAttribute::ON);

geode->getOrCreateStateSet()->setRenderingHint(osg::StateSet::TRANSPARENT_BIN);

pAddToThisGroup->addChild(geode);

}

return pAddToThisGroup;

}

} // namespace d3