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

/// @file Images.cpp

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

/// @date 2015.05.06

/// @brief Display an images in 3D

///

/// @attention Copyright (C) 2015

/// @attention All rights reserved

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

#include "Images.h"

#include <osg/Geometry>

#include <osg/Texture2D>

#include <osg/Geode>

#include <osg/TexEnv>

namespace d3

{

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

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

osg::ref_ptr<osg::Node> get(const ImageVec_t& images)

{

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

for ( const auto& image : images )

{

// here we create a quad that will be texture mapped with the image

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

quad->push_back( image.corners[0] );

quad->push_back( image.corners[1] );

quad->push_back( image.corners[2] );

quad->push_back( image.corners[3] );

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

geo->setVertexArray( quad );

// here we create a drawing elelment to draw on

osg::ref_ptr<osg::DrawElementsUInt>

primitiveSet( new osg::DrawElementsUInt(osg::PrimitiveSet::QUADS, 0) );

primitiveSet->push_back( 0 );

primitiveSet->push_back( 1 );

primitiveSet->push_back( 2 );

primitiveSet->push_back( 3 );

geo->addPrimitiveSet( primitiveSet );

// the texture mappings

osg::ref_ptr<osg::Vec2Array> texCoords( new osg::Vec2Array(4) );

(*texCoords)[3].set( 0.0f, 0.0f );

(*texCoords)[2].set( 1.0f, 0.0f );

(*texCoords)[1].set( 1.0f, 1.0f );

(*texCoords)[0].set( 0.0f, 1.0f );

geo->setTexCoordArray( 0, texCoords );

// now create the goede to hold our created geometry

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

geode->addDrawable( geo );

// create the texture for the image

osg::ref_ptr<osg::Texture2D> texture( new osg::Texture2D() );

texture->setResizeNonPowerOfTwoHint(false);

texture->setDataVariance(osg::Object::DYNAMIC);

texture->setImage( image.image );

// put this in decal mode

osg::ref_ptr<osg::TexEnv> decalTexEnv( new osg::TexEnv() );

decalTexEnv->setMode(osg::TexEnv::DECAL);

// set the state set, lighting and such, so we actually display the image

osg::ref_ptr<osg::StateSet> stateSet( geode->getOrCreateStateSet() );

stateSet->setTextureAttributeAndModes(0, texture, osg::StateAttribute::ON);

stateSet->setTextureAttribute(0, decalTexEnv);

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

geo->setStateSet(stateSet);

// turn off any color binding - we want to use the texture

geo->setColorBinding(osg::Geometry::BIND_OFF);

// add this image and continue

rv->addChild(geode);

}

return rv;

};

} // namespace d3