InfluenceMap::InfluenceMap(const size_t width, const size_t height, const bool clamp_values_to_0_1, const float initial_influence) :
_width(width), _height(height), _clamp_values_to_0_1(clamp_values_to_0_1)
{
// Of course, if width * height overflows size_t, we're screwed. No sane
// person would use values that large of course...
_data = new float[num_cells()];
_copy = new float[num_cells()];
const float clamped_influence = clamp_influence(initial_influence);
for (size_t i = 0; i < num_cells(); i++) {
_data[i] = clamped_influence;
_copy[i] = clamped_influence;
}
}
// Implements a greedy algorithm that split cells using the bisection until a target cell size is
// reached
std::tuple<std::vector<Partition>, std::vector<std::uint32_t>>
bisectionToPartition(const std::vector<BisectionID> &node_to_bisection_id,
const std::vector<std::size_t> &max_cell_sizes)
{
std::vector<std::uint32_t> permutation(node_to_bisection_id.size());
std::iota(permutation.begin(), permutation.end(), 0);
std::vector<CellBisection> cells;
cells.push_back(CellBisection{
0, static_cast<std::uint32_t>(node_to_bisection_id.size()), NUM_BISECTION_BITS - 1, false});
std::vector<Partition> partitions(max_cell_sizes.size());
std::vector<std::uint32_t> num_cells(max_cell_sizes.size());
int level_idx = max_cell_sizes.size() - 1;
for (auto max_cell_size : boost::adaptors::reverse(max_cell_sizes))
{
BOOST_ASSERT(level_idx >= 0);
partitionLevel(node_to_bisection_id, max_cell_size, permutation, cells);
partitions[level_idx] = cellsToPartition(cells, permutation);
num_cells[level_idx] = cells.size();
level_idx--;
}
return std::make_tuple(std::move(partitions), std::move(num_cells));
}
void InfluenceMap::propagate(const float momentum, const float decay)
{
float connections_array[InfluenceMap::CONNECTIONS_ARRAY_LENGTH];
size_t x = 0;
size_t y = 0;
const float edge_distance = 1.0f;
const float corner_distance = 1.414f;
const float edge = expf(-edge_distance * decay);
const float corner = expf(-corner_distance * decay);
for (size_t i = 0; i < num_cells(); i++) {
connections(x, y, connections_array, 1, 0);
// Spread //////////////////////////////////////////////////////
float max_influence = 0;
float neighbour_influence;
neighbour_influence = connections_array[ConnectionIndex::TopLeft] * corner;
if (neighbour_influence > max_influence) max_influence = neighbour_influence;
neighbour_influence = connections_array[ConnectionIndex::TopMiddle] * edge;
if (neighbour_influence > max_influence) max_influence = neighbour_influence;
neighbour_influence = connections_array[ConnectionIndex::TopRight] * corner;
if (neighbour_influence > max_influence) max_influence = neighbour_influence;
neighbour_influence = connections_array[ConnectionIndex::MiddleRight] * edge;
if (neighbour_influence > max_influence) max_influence = neighbour_influence;
neighbour_influence = connections_array[ConnectionIndex::BottomRight] * corner;
if (neighbour_influence > max_influence) max_influence = neighbour_influence;
neighbour_influence = connections_array[ConnectionIndex::BottomMiddle] * edge;
if (neighbour_influence > max_influence) max_influence = neighbour_influence;
neighbour_influence = connections_array[ConnectionIndex::BottomLeft] * corner;
if (neighbour_influence > max_influence) max_influence = neighbour_influence;
neighbour_influence = connections_array[ConnectionIndex::MiddleLeft] * edge;
if (neighbour_influence > max_influence) max_influence = neighbour_influence;
// lerp ////////////////////////////////////////////////////////
const float cur_influence = influence(x, y);
const float result = (max_influence - cur_influence) * momentum + cur_influence;
_copy[i] = clamp_influence(result);
// Move on
if (++x >= _width) {
x = 0;
y++;
}
}
// Swap the buffers
float * const tmp = _copy;
_copy = _data;
_data = tmp;
}
void IrradianceVolume::write( DataStream& stream )
{
stream.write_t(m_width);
stream.write_t(m_height);
stream.write_t(m_depth);
stream.write_t(m_position);
stream.write_t(m_dimensions);
stream.write_t(m_cell_size);
uint32 size = num_cells();
for(uint32 i=0; i<size; ++i )
{
stream.write_t(m_cells[i]);
}
}
Problem::Problem (Input input_param) {
/* Retrieve input parameters */
int num_reg = input_param.get_num_reg();
Col<int> num_cells = input_param.get_num_cells();
vec reg_size = input_param.get_reg_size();
string quad_type = input_param.get_quad_type();
Col<int> quad_order = input_param.get_quad_order();
vec abs_xs = input_param.get_abs_xs();
vec scat_xs = input_param.get_scat_xs();
vec ext_source = input_param.get_ext_source();
/* Create vector of pointers to each region */
Regions.resize(num_reg);
for (int i=0; i<num_reg; i++){
Regions[i] = new Region(quad_order(i), num_cells(i), reg_size(i), \
abs_xs(i), scat_xs(i), ext_source(i), quad_type);
}
}
bool IrradianceVolume::read( DataStream& stream )
{
delete m_cells;
stream.read_t(m_width);
stream.read_t(m_height);
stream.read_t(m_depth);
stream.read_t(m_position);
stream.read_t(m_dimensions);
stream.read_t(m_cell_size);
const uint32 size = num_cells();
m_cells = new SphericalHarmonics3[size];
for(uint32 i=0; i<size; ++i )
{
stream.read_t(m_cells[i]);
}
return true;
}
