VolumeObject.cpp

#include <Engine/Data/VolumeObject.hpp>
 
#include <Core/Geometry/MeshPrimitives.hpp>
#include <Core/Geometry/Volume.hpp>
#include <Core/Types.hpp>
#include <Core/Utils/Log.hpp>
#include <Engine/Data/ShaderProgram.hpp>
#include <Engine/OpenGL.hpp>
 
namespace Ra {
namespace Engine {
namespace Data {
VolumeObject::VolumeObject( const std::string& name ) :
    Displayable( name ), m_mesh( name + "_internal" ) {}
 
VolumeObject::~VolumeObject() {}
 
void VolumeObject::loadGeometry( Core::Geometry::AbstractVolume* volume, const Core::Aabb& aabb ) {
    if ( volume != nullptr && volume->isDense() ) {
 
        m_mesh.loadGeometry( Core::Geometry::makeSharpBox( aabb ) );
 
        Core::Vector3Array tex_coords;
        tex_coords.resize( 24 );
        tex_coords.getMap() <<
            // R
            Scalar( 1 ),
            Scalar( 1 ), Scalar( 0 ), Scalar( 0 ),              // Bottom
            Scalar( 1 ), Scalar( 0 ), Scalar( 0 ), Scalar( 1 ), // Top
            Scalar( 1 ), Scalar( 1 ), Scalar( 1 ), Scalar( 1 ), // Right
            Scalar( 0 ), Scalar( 0 ), Scalar( 0 ), Scalar( 0 ), // Left
            Scalar( 1 ), Scalar( 0 ), Scalar( 0 ), Scalar( 1 ), // Floor
            Scalar( 1 ), Scalar( 1 ), Scalar( 0 ), Scalar( 0 ), // Ceil
            // G
            Scalar( 0 ), Scalar( 1 ), Scalar( 1 ), Scalar( 0 ), // Bottom
            Scalar( 0 ), Scalar( 0 ), Scalar( 1 ), Scalar( 1 ), // Top
            Scalar( 1 ), Scalar( 0 ), Scalar( 0 ), Scalar( 1 ), // Right
            Scalar( 0 ), Scalar( 1 ), Scalar( 1 ), Scalar( 0 ), // Left
            Scalar( 0 ), Scalar( 0 ), Scalar( 0 ), Scalar( 0 ), // Floor
            Scalar( 1 ), Scalar( 1 ), Scalar( 1 ), Scalar( 1 ), // Ceil
            // B
            Scalar( 0 ), Scalar( 0 ), Scalar( 0 ), Scalar( 0 ), // Bottom
            Scalar( 1 ), Scalar( 1 ), Scalar( 1 ), Scalar( 1 ), // Top
            Scalar( 0 ), Scalar( 0 ), Scalar( 1 ), Scalar( 1 ), // Right
            Scalar( 0 ), Scalar( 0 ), Scalar( 1 ), Scalar( 1 ), // Left
            Scalar( 0 ), Scalar( 0 ), Scalar( 1 ), Scalar( 1 ), // Floor
            Scalar( 0 ), Scalar( 1 ), Scalar( 1 ), Scalar( 0 ); // Ceil
        m_mesh.addAttrib( Ra::Core::Geometry::getAttribName( Ra::Core::Geometry::VERTEX_TEXCOORD ),
                          tex_coords );
 
        Core::Geometry::VolumeGrid* grid = static_cast<Core::Geometry::VolumeGrid*>( volume );
        m_volume = std::unique_ptr<Core::Geometry::AbstractVolume>( volume );
 
        auto dim = grid->size();
 
        // tmp hack create a shared ptr and copy to it.
        std::shared_ptr<float[]> data( new float[grid->data().size()] );
        auto itr = data.get();
        for ( const auto& v : grid->data() ) {
            *( itr++ ) = v;
        }
        TextureParameters texparam {
            getName(),
            { GL_CLAMP_TO_BORDER, GL_CLAMP_TO_BORDER, GL_CLAMP_TO_BORDER, GL_LINEAR, GL_LINEAR },
            { GL_TEXTURE_3D,
              size_t( dim( 0 ) ),
              size_t( dim( 1 ) ),
              size_t( dim( 2 ) ),
              GL_RED,
              GL_R32F,
              GL_SCALAR,
              false,
              data } };
        m_tex.setParameters( texparam );
 
        m_isDirty = true;
    }
}
 
void VolumeObject::loadGeometry( Core::Geometry::AbstractVolume* volume ) {
    loadGeometry( volume, volume->computeAabb() );
}
 
void VolumeObject::updateGL() {
    if ( m_isDirty ) {
        m_mesh.updateGL();
        GL_CHECK_ERROR;
        m_tex.initialize();
        GL_CHECK_ERROR;
        m_isDirty = false;
    }
}
 
void VolumeObject::render( const ShaderProgram* prog ) {
    GL_CHECK_ERROR;
    // Cull faces
 
    GLboolean cullEnable = glIsEnabled( GL_CULL_FACE );
    int culledFaces;
    glGetIntegerv( GL_CULL_FACE_MODE, &culledFaces );
    int frontFaces;
    glGetIntegerv( GL_FRONT_FACE, &frontFaces );
    glCullFace( GL_BACK );
    glEnable( GL_CULL_FACE );
 
    m_mesh.render( prog );
 
    glCullFace( gl::GLenum( culledFaces ) );
    glFrontFace( gl::GLenum( frontFaces ) );
    if ( !cullEnable ) glDisable( GL_CULL_FACE );
    GL_CHECK_ERROR;
}
 
} // namespace Data
} // namespace Engine
} // namespace Ra