void triangulate_visitor::copy_face( mesh_model_t& model,
const shape_t& shape,
std::size_t index,
boost::uint32_t face_start_index,
mesh_model_t& new_model,
shape_t& new_shape)
{
arrays::const_array_ref_t<boost::uint32_t> verts_per_face( model.const_verts_per_face_array());
arrays::const_array_ref_t<boost::uint32_t> face_vert_indices( model.const_face_vert_indices_array());
arrays::array_ref_t<boost::uint32_t> new_verts_per_face( new_model.verts_per_face_array());
arrays::array_ref_t<boost::uint32_t> new_face_vert_indices( new_model.face_vert_indices_array());
int num_verts = verts_per_face[index];
new_verts_per_face.push_back( num_verts);
for( int i = 0; i < num_verts; ++i)
{
int vertex_num = face_vert_indices[face_start_index +i];
new_face_vert_indices.push_back( vertex_num);
new_shape.attributes().vertex().push_back_attribute_values_copy( shape.attributes().vertex(),
vertex_num);
}
// copy face attributes
new_shape.attributes().primitive().push_back_attribute_values_copy( shape.attributes().primitive(),
index);
}
virtual void visit( visitable_t& model, shape_t& shape)
{
detail::transform_dictionary( shape.attributes().constant() , xform_);
detail::transform_attribute_table( shape.attributes().primitive(), xform_);
detail::transform_attribute_table( shape.attributes().vertex() , xform_);
detail::transform_attribute_table( shape.attributes().point() , xform_);
}
void compute_face_normals_visitor::do_visit( mesh_model_t& model, shape_t& shape)
{
if( !shape.attributes().point().has_attribute( g_P_name))
throw core::runtime_error( core::string8_t( "No P attribute found in compute face normals visitor"));
// create the N array, if it does not exist.
if( shape.attributes().primitive().has_attribute( g_N_name))
{
arrays::array_t N( core::normalf_k);
N.reserve( model.num_faces());
shape.attributes().primitive().insert( g_N_name, N);
}
arrays::const_array_ref_t<math::point3f_t> points( shape.attributes().point().const_array( g_P_name));
arrays::const_array_ref_t<boost::uint32_t> verts_per_face( model.const_verts_per_face_array());
arrays::const_array_ref_t<boost::uint32_t> face_vert_indices( model.const_face_vert_indices_array());
arrays::array_ref_t<math::normalf_t> normals( shape.attributes().primitive().array( g_N_name));
boost::uint32_t face_start_index = 0;
for( int i = 0, e = model.num_faces(); i < e; ++i)
{
boost::uint32_t num_verts = verts_per_face[i];
boost::optional<math::normalf_t> n = newell_polygon_normal( boost::make_permutation_iterator( points.begin(),
face_vert_indices.begin() + face_start_index),
boost::make_permutation_iterator( points.begin(),
face_vert_indices.begin() + face_start_index + num_verts));
if( n)
normals[i] = n.get();
face_start_index += num_verts;
}
}
void triangulate_visitor::visit( subd_mesh_model_t& model, shape_t& shape)
{
if( !shape.attributes().point().has_attribute( g_P_name))
throw core::runtime_error( core::string8_t( "No P attribute found in triangulate visitor"));
shape_t new_shape( shape_t::create_subd_mesh());
subd_mesh_model_t& new_model( shape_cast<subd_mesh_model_t>( new_shape));
do_visit( model, shape, new_model, new_shape);
}
void triangulate_visitor::do_visit( mesh_model_t& model,
shape_t& shape,
mesh_model_t& new_model,
shape_t& new_shape)
{
// copy attributes
new_shape.attributes().point() = shape.attributes().point();
new_shape.attributes().constant() = shape.attributes().constant();
new_shape.attributes().vertex() = attribute_table_t::create_empty_with_same_attributes( shape.attributes().vertex());
new_shape.attributes().primitive() = attribute_table_t::create_empty_with_same_attributes( shape.attributes().primitive());
arrays::const_array_ref_t<math::point3f_t> points( shape.attributes().point().const_array( g_P_name));
arrays::const_array_ref_t<boost::uint32_t> verts_per_face( model.const_verts_per_face_array());
arrays::const_array_ref_t<boost::uint32_t> face_vert_indices( model.const_face_vert_indices_array());
boost::uint32_t face_start_index = 0;
for( int i = 0, e = model.num_faces(); i < e; ++i)
{
boost::uint32_t num_verts = verts_per_face[i];
if( num_verts == 3)
copy_face( model, shape, i, face_start_index, new_model, new_shape);
else
{
if( num_verts == 4)
{
if( keep_quads_)
copy_face( model, shape, i, face_start_index, new_model, new_shape);
else
triangulate_quad( model, shape, i, face_start_index, new_model, new_shape);
}
else
{
// TODO: triangulate polygon here
throw core::not_implemented();
}
}
face_start_index += num_verts;
}
shape.swap( new_shape);
throw core::not_implemented();
}
void triangulate_visitor::triangulate_quad( mesh_model_t& model,
const shape_t& shape,
std::size_t index,
boost::uint32_t face_start_index,
mesh_model_t& new_model,
shape_t& new_shape)
{
arrays::const_array_ref_t<boost::uint32_t> verts_per_face( model.const_verts_per_face_array());
arrays::const_array_ref_t<boost::uint32_t> face_vert_indices( model.const_face_vert_indices_array());
arrays::array_ref_t<boost::uint32_t> new_verts_per_face( new_model.verts_per_face_array());
arrays::array_ref_t<boost::uint32_t> new_face_vert_indices( new_model.face_vert_indices_array());
assert( verts_per_face[index] == 4);
// First triangle
new_verts_per_face.push_back( 3);
new_face_vert_indices.push_back( face_vert_indices[face_start_index]);
new_shape.attributes().vertex().push_back_attribute_values_copy( shape.attributes().vertex(),
face_start_index);
new_face_vert_indices.push_back( face_vert_indices[face_start_index + 1]);
new_shape.attributes().vertex().push_back_attribute_values_copy( shape.attributes().vertex(),
face_start_index + 1);
new_face_vert_indices.push_back( face_vert_indices[face_start_index + 3]);
new_shape.attributes().vertex().push_back_attribute_values_copy( shape.attributes().vertex(),
face_start_index + 3);
new_shape.attributes().primitive().push_back_attribute_values_copy( shape.attributes().primitive(),
index);
// Second triangle
new_verts_per_face.push_back( 3);
new_face_vert_indices.push_back( face_vert_indices[face_start_index + 1]);
new_shape.attributes().vertex().push_back_attribute_values_copy( shape.attributes().vertex(),
face_start_index + 1);
new_face_vert_indices.push_back( face_vert_indices[face_start_index + 2]);
new_shape.attributes().vertex().push_back_attribute_values_copy( shape.attributes().vertex(),
face_start_index + 2);
new_face_vert_indices.push_back( face_vert_indices[face_start_index + 3]);
new_shape.attributes().vertex().push_back_attribute_values_copy( shape.attributes().vertex(),
face_start_index + 3);
new_shape.attributes().primitive().push_back_attribute_values_copy( shape.attributes().primitive(),
index);
}
