// This file contains liberal use of asserts to assist code development and
// debugging. Standard matplotlib builds disable asserts so they cause no
// performance reduction. To enable the asserts, you need to undefine the
// NDEBUG macro, which is achieved by adding the following
// undef_macros=['NDEBUG']
// to the appropriate make_extension call in setupext.py, and then rebuilding.
#define NO_IMPORT_ARRAY
#include "src/mplutils.h"
#include "src/_contour.h"
#include <algorithm>
// 'kind' codes.
#define MOVETO 1
#define LINETO 2
#define CLOSEPOLY 79
// Point indices from current quad index.
#define POINT_SW (quad)
#define POINT_SE (quad+1)
#define POINT_NW (quad+_nx)
#define POINT_NE (quad+_nx+1)
// CacheItem masks, only accessed directly to set. To read, use accessors
// detailed below. 1 and 2 refer to level indices (lower and upper).
#define MASK_Z_LEVEL 0x0003 // Combines the following two.
#define MASK_Z_LEVEL_1 0x0001 // z > lower_level.
#define MASK_Z_LEVEL_2 0x0002 // z > upper_level.
#define MASK_VISITED_1 0x0004 // Algorithm has visited this quad.
#define MASK_VISITED_2 0x0008
#define MASK_SADDLE_1 0x0010 // quad is a saddle quad.
#define MASK_SADDLE_2 0x0020
#define MASK_SADDLE_LEFT_1 0x0040 // Contours turn left at saddle quad.
#define MASK_SADDLE_LEFT_2 0x0080
#define MASK_SADDLE_START_SW_1 0x0100 // Next visit starts on S or W edge.
#define MASK_SADDLE_START_SW_2 0x0200
#define MASK_BOUNDARY_S 0x0400 // S edge of quad is a boundary.
#define MASK_BOUNDARY_W 0x0800 // W edge of quad is a boundary.
// EXISTS_QUAD bit is always used, but the 4 EXISTS_CORNER are only used if
// _corner_mask is true. Only one of EXISTS_QUAD or EXISTS_??_CORNER is ever
// set per quad, hence not using unique bits for each; care is needed when
// testing for these flags as they overlap.
#define MASK_EXISTS_QUAD 0x1000 // All of quad exists (is not masked).
#define MASK_EXISTS_SW_CORNER 0x2000 // SW corner exists, NE corner is masked.
#define MASK_EXISTS_SE_CORNER 0x3000
#define MASK_EXISTS_NW_CORNER 0x4000
#define MASK_EXISTS_NE_CORNER 0x5000
#define MASK_EXISTS 0x7000 // Combines all 5 EXISTS masks.
// The following are only needed for filled contours.
#define MASK_VISITED_S 0x10000 // Algorithm has visited S boundary.
#define MASK_VISITED_W 0x20000 // Algorithm has visited W boundary.
#define MASK_VISITED_CORNER 0x40000 // Algorithm has visited corner edge.
// Accessors for various CacheItem masks. li is shorthand for level_index.
#define Z_LEVEL(quad) (_cache[quad] & MASK_Z_LEVEL)
#define Z_NE Z_LEVEL(POINT_NE)
#define Z_NW Z_LEVEL(POINT_NW)
#define Z_SE Z_LEVEL(POINT_SE)
#define Z_SW Z_LEVEL(POINT_SW)
#define VISITED(quad,li) (_cache[quad] & (li==1 ? MASK_VISITED_1 : MASK_VISITED_2))
#define VISITED_S(quad) (_cache[quad] & MASK_VISITED_S)
#define VISITED_W(quad) (_cache[quad] & MASK_VISITED_W)
#define VISITED_CORNER(quad) (_cache[quad] & MASK_VISITED_CORNER)
#define SADDLE(quad,li) (_cache[quad] & (li==1 ? MASK_SADDLE_1 : MASK_SADDLE_2))
#define SADDLE_LEFT(quad,li) (_cache[quad] & (li==1 ? MASK_SADDLE_LEFT_1 : MASK_SADDLE_LEFT_2))
#define SADDLE_START_SW(quad,li) (_cache[quad] & (li==1 ? MASK_SADDLE_START_SW_1 : MASK_SADDLE_START_SW_2))
#define BOUNDARY_S(quad) (_cache[quad] & MASK_BOUNDARY_S)
#define BOUNDARY_W(quad) (_cache[quad] & MASK_BOUNDARY_W)
#define BOUNDARY_N(quad) BOUNDARY_S(quad+_nx)
#define BOUNDARY_E(quad) BOUNDARY_W(quad+1)
#define EXISTS_QUAD(quad) ((_cache[quad] & MASK_EXISTS) == MASK_EXISTS_QUAD)
#define EXISTS_NONE(quad) ((_cache[quad] & MASK_EXISTS) == 0)
// The following are only used if _corner_mask is true.
#define EXISTS_SW_CORNER(quad) ((_cache[quad] & MASK_EXISTS) == MASK_EXISTS_SW_CORNER)
#define EXISTS_SE_CORNER(quad) ((_cache[quad] & MASK_EXISTS) == MASK_EXISTS_SE_CORNER)
#define EXISTS_NW_CORNER(quad) ((_cache[quad] & MASK_EXISTS) == MASK_EXISTS_NW_CORNER)
#define EXISTS_NE_CORNER(quad) ((_cache[quad] & MASK_EXISTS) == MASK_EXISTS_NE_CORNER)
#define EXISTS_ANY_CORNER(quad) (!EXISTS_NONE(quad) && !EXISTS_QUAD(quad))
#define EXISTS_W_EDGE(quad) (EXISTS_QUAD(quad) || EXISTS_SW_CORNER(quad) || EXISTS_NW_CORNER(quad))
#define EXISTS_E_EDGE(quad) (EXISTS_QUAD(quad) || EXISTS_SE_CORNER(quad) || EXISTS_NE_CORNER(quad))
#define EXISTS_S_EDGE(quad) (EXISTS_QUAD(quad) || EXISTS_SW_CORNER(quad) || EXISTS_SE_CORNER(quad))
#define EXISTS_N_EDGE(quad) (EXISTS_QUAD(quad) || EXISTS_NW_CORNER(quad) || EXISTS_NE_CORNER(quad))
// Note that EXISTS_NE_CORNER(quad) is equivalent to BOUNDARY_SW(quad), etc.
QuadEdge::QuadEdge()
: quad(-1), edge(Edge_None)
{}
QuadEdge::QuadEdge(long quad_, Edge edge_)
: quad(quad_), edge(edge_)
{}
bool QuadEdge::operator<(const QuadEdge& other) const
{
if (quad != other.quad)
return quad < other.quad;
else
return edge < other.edge;
}
bool QuadEdge::operator==(const QuadEdge& other) const
{
return quad == other.quad && edge == other.edge;
}
bool QuadEdge::operator!=(const QuadEdge& other) const
{
return !operator==(other);
}
std::ostream& operator<<(std::ostream& os, const QuadEdge& quad_edge)
{
return os << quad_edge.quad << ' ' << quad_edge.edge;
}
// conflict with code from matplotlib/tri/_tri.cpp
#if 0
XY::XY()
{}
XY::XY(const double& x_, const double& y_)
: x(x_), y(y_)
{}
bool XY::operator==(const XY& other) const
{
return x == other.x && y == other.y;
}
bool XY::operator!=(const XY& other) const
{
return x != other.x || y != other.y;
}
XY XY::operator*(const double& multiplier) const
{
return XY(x*multiplier, y*multiplier);
}
const XY& XY::operator+=(const XY& other)
{
x += other.x;
y += other.y;
return *this;
}
const XY& XY::operator-=(const XY& other)
{
x -= other.x;
y -= other.y;
return *this;
}
XY XY::operator+(const XY& other) const
{
return XY(x + other.x, y + other.y);
}
XY XY::operator-(const XY& other) const
{
return XY(x - other.x, y - other.y);
}
std::ostream& operator<<(std::ostream& os, const XY& xy)
{
return os << '(' << xy.x << ' ' << xy.y << ')';
}
#endif
ContourLine::ContourLine(bool is_hole)
: std::vector<XY>(),
_is_hole(is_hole),
_parent(0)
{}
void ContourLine::add_child(ContourLine* child)
{
assert(!_is_hole && "Cannot add_child to a hole");
assert(child != 0 && "Null child ContourLine");
_children.push_back(child);
}
void ContourLine::clear_parent()
{
assert(is_hole() && "Cannot clear parent of non-hole");
assert(_parent != 0 && "Null parent ContourLine");
_parent = 0;
}
const ContourLine::Children& ContourLine::get_children() const
{
assert(!_is_hole && "Cannot get_children of a hole");
return _children;
}
const ContourLine* ContourLine::get_parent() const
{
assert(_is_hole && "Cannot get_parent of a non-hole");
return _parent;
}
ContourLine* ContourLine::get_parent()
{
assert(_is_hole && "Cannot get_parent of a non-hole");
return _parent;
}
bool ContourLine::is_hole() const
{
return _is_hole;
}
// conflict with code from matplotlib/tri/_tri.cpp
#if 0
void ContourLine::push_back(const XY& point)
{
if (empty() || point != back())
std::vector<XY>::push_back(point);
}
#endif
void ContourLine::set_parent(ContourLine* parent)
{
assert(_is_hole && "Cannot set parent of a non-hole");
assert(parent != 0 && "Null parent ContourLine");
_parent = parent;
}
// conflict with code from matplotlib/tri/_tri.cpp
#if 0
void ContourLine::write() const
{
std::cout << "ContourLine " << this << " of " << size() << " points:";
for (const_iterator it = begin(); it != end(); ++it)
std::cout << ' ' << *it;
if (is_hole())
std::cout << " hole, parent=" << get_parent();
else {
std::cout << " not hole";
if (!_children.empty()) {
std::cout << ", children=";
for (Children::const_iterator it = _children.begin();
it != _children.end(); ++it)
std::cout << *it << ' ';
}
}
std::cout << std::endl;
}
#endif
Contour::Contour()
{}
Contour::~Contour()
{
delete_contour_lines();
}
void Contour::delete_contour_lines()
{
for (iterator line_it = begin(); line_it != end(); ++line_it) {
delete *line_it;
*line_it = 0;
}
std::vector<ContourLine*>::clear();
}
void Contour::write() const
{
std::cout << "Contour of " << size() << " lines." << std::endl;
for (const_iterator it = begin(); it != end(); ++it)
(*it)->write();
}
ParentCache::ParentCache(long nx, long x_chunk_points, long y_chunk_points)
: _nx(nx),
_x_chunk_points(x_chunk_points),
_y_chunk_points(y_chunk_points),
_lines(0), // Initialised when first needed.
_istart(0),
_jstart(0)
{
assert(_x_chunk_points > 0 && _y_chunk_points > 0 &&
"Chunk sizes must be positive");
}
ContourLine* ParentCache::get_parent(long quad)
{
long index = quad_to_index(quad);
ContourLine* parent = _lines[index];
while (parent == 0) {
index -= _x_chunk_points;
assert(index >= 0 && "Failed to find parent in chunk ParentCache");
parent = _lines[index];
}
assert(parent != 0 && "Failed to find parent in chunk ParentCache");
return parent;
}
long ParentCache::quad_to_index(long quad) const
{
long i = quad % _nx;
long j = quad / _nx;
long index = (i-_istart) + (j-_jstart)*_x_chunk_points;
assert(i >= _istart && i < _istart + _x_chunk_points &&
"i-index outside chunk");
assert(j >= _jstart && j < _jstart + _y_chunk_points &&
"j-index outside chunk");
assert(index >= 0 && index < static_cast<long>(_lines.size()) &&
"ParentCache index outside chunk");
return index;
}
void ParentCache::set_chunk_starts(long istart, long jstart)
{
assert(istart >= 0 && jstart >= 0 &&
"Chunk start indices cannot be negative");
_istart = istart;
_jstart = jstart;
if (_lines.empty())
_lines.resize(_x_chunk_points*_y_chunk_points, 0);
else
std::fill(_lines.begin(), _lines.end(), (ContourLine*)0);
}
void ParentCache::set_parent(long quad, ContourLine& contour_line)
{
assert(!_lines.empty() &&
"Accessing ParentCache before it has been initialised");
long index = quad_to_index(quad);
if (_lines[index] == 0)
_lines[index] = (contour_line.is_hole() ? contour_line.get_parent()
: &contour_line);
}
QuadContourGenerator::QuadContourGenerator(const CoordinateArray& x,
const CoordinateArray& y,
const CoordinateArray& z,
const MaskArray& mask,
bool corner_mask,
long chunk_size)
: _x(x),
_y(y),
_z(z),
_nx(static_cast<long>(_x.dim(1))),
_ny(static_cast<long>(_x.dim(0))),
_n(_nx*_ny),
_corner_mask(corner_mask),
_chunk_size(chunk_size > 0 ? std::min(chunk_size, std::max(_nx, _ny)-1)
: std::max(_nx, _ny)-1),
_nxchunk(calc_chunk_count(_nx)),
_nychunk(calc_chunk_count(_ny)),
_chunk_count(_nxchunk*_nychunk),
_cache(new CacheItem[_n]),
_parent_cache(_nx,
chunk_size > 0 ? chunk_size+1 : _nx,
chunk_size > 0 ? chunk_size+1 : _ny)
{
assert(!_x.empty() && !_y.empty() && !_z.empty() && "Empty array");
assert(_y.dim(0) == _x.dim(0) && _y.dim(1) == _x.dim(1) &&
"Different-sized y and x arrays");
assert(_z.dim(0) == _x.dim(0) && _z.dim(1) == _x.dim(1) &&
"Different-sized z and x arrays");
assert((mask.empty() ||
(mask.dim(0) == _x.dim(0) && mask.dim(1) == _x.dim(1))) &&
"Different-sized mask and x arrays");
init_cache_grid(mask);
}
QuadContourGenerator::~QuadContourGenerator()
{
delete [] _cache;
}
void QuadContourGenerator::append_contour_line_to_vertices(
ContourLine& contour_line,
PyObject* vertices_list) const
{
assert(vertices_list != 0 && "Null python vertices_list");
// Convert ContourLine to python equivalent, and clear it.
npy_intp dims[2] = {static_cast<npy_intp>(contour_line.size()), 2};
numpy::array_view<double, 2> line(dims);
npy_intp i = 0;
for (ContourLine::const_iterator point = contour_line.begin();
point != contour_line.end(); ++point, ++i) {
line(i, 0) = point->x;
line(i, 1) = point->y;
}
if (PyList_Append(vertices_list, line.pyobj_steal())) {
Py_XDECREF(vertices_list);
throw std::runtime_error("Unable to add contour line to vertices_list");
}
contour_line.clear();
}
void QuadContourGenerator::append_contour_to_vertices_and_codes(
Contour& contour,
PyObject* vertices_list,
PyObject* codes_list) const
{
assert(vertices_list != 0 && "Null python vertices_list");
assert(codes_list != 0 && "Null python codes_list");
// Convert Contour to python equivalent, and clear it.
for (Contour::iterator line_it = contour.begin(); line_it != contour.end();
++line_it) {
ContourLine& line = **line_it;
if (line.is_hole()) {
// If hole has already been converted to python its parent will be
// set to 0 and it can be deleted.
if (line.get_parent() != 0) {
delete *line_it;
*line_it = 0;
}
}
else {
// Non-holes are converted to python together with their child
// holes so that they are rendered correctly.
ContourLine::const_iterator point;
ContourLine::Children::const_iterator children_it;
const ContourLine::Children& children = line.get_children();
npy_intp npoints = static_cast<npy_intp>(line.size() + 1);
for (children_it = children.begin(); children_it != children.end();
++children_it)
npoints += static_cast<npy_intp>((*children_it)->size() + 1);
npy_intp vertices_dims[2] = {npoints, 2};
numpy::array_view<double, 2> vertices(vertices_dims);
double* vertices_ptr = vertices.data();
npy_intp codes_dims[1] = {npoints};
numpy::array_view<unsigned char, 1> codes(codes_dims);
unsigned char* codes_ptr = codes.data();
for (point = line.begin(); point != line.end(); ++point) {
*vertices_ptr++ = point->x;
*vertices_ptr++ = point->y;
*codes_ptr++ = (point == line.begin() ? MOVETO : LINETO);
}
point = line.begin();
*vertices_ptr++ = point->x;
*vertices_ptr++ = point->y;
*codes_ptr++ = CLOSEPOLY;
for (children_it = children.begin(); children_it != children.end();
++children_it) {
ContourLine& child = **children_it;
for (point = child.begin(); point != child.end(); ++point) {
*vertices_ptr++ = point->x;
*vertices_ptr++ = point->y;
*codes_ptr++ = (point == child.begin() ? MOVETO : LINETO);
}
point = child.begin();
*vertices_ptr++ = point->x;
*vertices_ptr++ = point->y;
*codes_ptr++ = CLOSEPOLY;
child.clear_parent(); // To indicate it can be deleted.
}
if (PyList_Append(vertices_list, vertices.pyobj_steal()) ||
PyList_Append(codes_list, codes.pyobj_steal())) {
Py_XDECREF(vertices_list);
Py_XDECREF(codes_list);
contour.delete_contour_lines();
throw std::runtime_error("Unable to add contour line to vertices and codes lists");
}
delete *line_it;
*line_it = 0;
}
}
// Delete remaining contour lines.
contour.delete_contour_lines();
}
long QuadContourGenerator::calc_chunk_count(long point_count) const
{
assert(point_count > 0 && "point count must be positive");
assert(_chunk_size > 0 && "Chunk size must be positive");
if (_chunk_size > 0) {
long count = (point_count-1) / _chunk_size;
if (count*_chunk_size < point_count-1)
++count;
assert(count >= 1 && "Invalid chunk count");
return count;
}
else
return 1;
}
PyObject* QuadContourGenerator::create_contour(const double& level)
{
init_cache_levels(level, level);
PyObject* vertices_list = PyList_New(0);
if (vertices_list == 0)
throw std::runtime_error("Failed to create Python list");
// Lines that start and end on boundaries.
long ichunk, jchunk, istart, iend, jstart, jend;
for (long ijchunk = 0; ijchunk < _chunk_count; ++ijchunk) {
get_chunk_limits(ijchunk, ichunk, jchunk, istart, iend, jstart, jend);
for (long j = jstart; j < jend; ++j) {
long quad_end = iend + j*_nx;
for (long quad = istart + j*_nx; quad < quad_end; ++quad) {
if (EXISTS_NONE(quad) || VISITED(quad,1)) continue;
if (BOUNDARY_S(quad) && Z_SW >= 1 && Z_SE < 1 &&
start_line(vertices_list, quad, Edge_S, level)) continue;
if (BOUNDARY_W(quad) && Z_NW >= 1 && Z_SW < 1 &&
start_line(vertices_list, quad, Edge_W, level)) continue;
if (BOUNDARY_N(quad) && Z_NE >= 1 && Z_NW < 1 &&
start_line(vertices_list, quad, Edge_N, level)) continue;
if (BOUNDARY_E(quad) && Z_SE >= 1 && Z_NE < 1 &&
start_line(vertices_list, quad, Edge_E, level)) continue;
if (_corner_mask) {
// Equates to NE boundary.
if (EXISTS_SW_CORNER(quad) && Z_SE >= 1 && Z_NW < 1 &&
start_line(vertices_list, quad, Edge_NE, level)) continue;
// Equates to NW boundary.
if (EXISTS_SE_CORNER(quad) && Z_NE >= 1 && Z_SW < 1 &&
start_line(vertices_list, quad, Edge_NW, level)) continue;
// Equates to SE boundary.
if (EXISTS_NW_CORNER(quad) && Z_SW >= 1 && Z_NE < 1 &&
start_line(vertices_list, quad, Edge_SE, level)) continue;
// Equates to SW boundary.
if (EXISTS_NE_CORNER(quad) && Z_NW >= 1 && Z_SE < 1 &&
start_line(vertices_list, quad, Edge_SW, level)) continue;
}
}
}
}
// Internal loops.
ContourLine contour_line(false); // Reused for each contour line.
for (long ijchunk = 0; ijchunk < _chunk_count; ++ijchunk) {
get_chunk_limits(ijchunk, ichunk, jchunk, istart, iend, jstart, jend);
for (long j = jstart; j < jend; ++j) {
long quad_end = iend + j*_nx;
for (long quad = istart + j*_nx; quad < quad_end; ++quad) {
if (EXISTS_NONE(quad) || VISITED(quad,1))
continue;
Edge start_edge = get_start_edge(quad, 1);
if (start_edge == Edge_None)
continue;
QuadEdge quad_edge(quad, start_edge);
QuadEdge start_quad_edge(quad_edge);
// To obtain output identical to that produced by legacy code,
// sometimes need to ignore the first point and add it on the
// end instead.
bool ignore_first = (start_edge == Edge_N);
follow_interior(contour_line, quad_edge, 1, level,
!ignore_first, &start_quad_edge, 1, false);
if (ignore_first && !contour_line.empty())
contour_line.push_back(contour_line.front());
append_contour_line_to_vertices(contour_line, vertices_list);
// Repeat if saddle point but not visited.
if (SADDLE(quad,1) && !VISITED(quad,1))
--quad;
}
}
}
return vertices_list;
}
PyObject* QuadContourGenerator::create_filled_contour(const double& lower_level,
const double& upper_level)
{
init_cache_levels(lower_level, upper_level);
Contour contour;
PyObject* vertices = PyList_New(0);
if (vertices == 0)
throw std::runtime_error("Failed to create Python list");
PyObject* codes = PyList_New(0);
if (codes == 0) {
Py_XDECREF(vertices);
throw std::runtime_error("Failed to create Python list");
}
long ichunk, jchunk, istart, iend, jstart, jend;
for (long ijchunk = 0; ijchunk < _chunk_count; ++ijchunk) {
get_chunk_limits(ijchunk, ichunk, jchunk, istart, iend, jstart, jend);
_parent_cache.set_chunk_starts(istart, jstart);
for (long j = jstart; j < jend; ++j) {
long quad_end = iend + j*_nx;
for (long quad = istart + j*_nx; quad < quad_end; ++quad) {
if (!EXISTS_NONE(quad))
single_quad_filled(contour, quad, lower_level, upper_level);
}
}
// Clear VISITED_W and VISITED_S flags that are reused by later chunks.
if (jchunk < _nychunk-1) {
long quad_end = iend + jend*_nx;
for (long quad = istart + jend*_nx; quad < quad_end; ++quad)
_cache[quad] &= ~MASK_VISITED_S;
}
if (ichunk < _nxchunk-1) {
long quad_end = iend + jend*_nx;
for (long quad = iend + jstart*_nx; quad < quad_end; quad += _nx)
_cache[quad] &= ~MASK_VISITED_W;
}
// Create python objects to return for this chunk.
append_contour_to_vertices_and_codes(contour, vertices, codes);
}
PyObject* tuple = PyTuple_New(2);
if (tuple == 0) {
Py_XDECREF(vertices);
Py_XDECREF(codes);
throw std::runtime_error("Failed to create Python tuple");
}
// No error checking here as filling in a brand new pre-allocated tuple.
PyTuple_SET_ITEM(tuple, 0, vertices);
PyTuple_SET_ITEM(tuple, 1, codes);
return tuple;
}
XY QuadContourGenerator::edge_interp(const QuadEdge& quad_edge,
const double& level)
{
assert(quad_edge.quad >= 0 && quad_edge.quad < _n &&
"Quad index out of bounds");
assert(quad_edge.edge != Edge_None && "Invalid edge");
return interp(get_edge_point_index(quad_edge, true),
get_edge_point_index(quad_edge, false),
level);
}
unsigned int QuadContourGenerator::follow_boundary(
ContourLine& contour_line,
QuadEdge& quad_edge,
const double& lower_level,
const double& upper_level,
unsigned int level_index,
const QuadEdge& start_quad_edge)
{
assert(quad_edge.quad >= 0 && quad_edge.quad < _n &&
"Quad index out of bounds");
assert(quad_edge.edge != Edge_None && "Invalid edge");
assert(is_edge_a_boundary(quad_edge) && "Not a boundary edge");
assert((level_index == 1 || level_index == 2) &&
"level index must be 1 or 2");
assert(start_quad_edge.quad >= 0 && start_quad_edge.quad < _n &&
"Start quad index out of bounds");
assert(start_quad_edge.edge != Edge_None && "Invalid start edge");
// Only called for filled contours, so always updates _parent_cache.
unsigned int end_level = 0;
bool first_edge = true;
bool stop = false;
long& quad = quad_edge.quad;
while (true) {
// Levels of start and end points of quad_edge.
unsigned int start_level =
(first_edge ? Z_LEVEL(get_edge_point_index(quad_edge, true))
: end_level);
long end_point = get_edge_point_index(quad_edge, false);
end_level = Z_LEVEL(end_point);
if (level_index == 1) {
if (start_level <= level_index && end_level == 2) {
// Increasing z, switching levels from 1 to 2.
level_index = 2;
stop = true;
}
else if (start_level >= 1 && end_level == 0) {
// Decreasing z, keeping same level.
stop = true;
}
}
else { // level_index == 2
if (start_level <= level_index && end_level == 2) {
// Increasing z, keeping same level.
stop = true;
}
else if (start_level >= 1 && end_level == 0) {
// Decreasing z, switching levels from 2 to 1.
level_index = 1;
stop = true;
}
}
if (!first_edge && !stop && quad_edge == start_quad_edge)
// Return if reached start point of contour line. Do this before
// checking/setting VISITED flags as will already have been
// visited.
break;
switch (quad_edge.edge) {
case Edge_E:
assert(!VISITED_W(quad+1) && "Already visited");
_cache[quad+1] |= MASK_VISITED_W;
break;
case Edge_N:
assert(!VISITED_S(quad+_nx) && "Already visited");
_cache[quad+_nx] |= MASK_VISITED_S;
break;
case Edge_W:
assert(!VISITED_W(quad) && "Already visited");
_cache[quad] |= MASK_VISITED_W;
break;
case Edge_S:
assert(!VISITED_S(quad) && "Already visited");
_cache[quad] |= MASK_VISITED_S;
break;
case Edge_NE:
case Edge_NW:
case Edge_SW:
case Edge_SE:
assert(!VISITED_CORNER(quad) && "Already visited");
_cache[quad] |= MASK_VISITED_CORNER;
break;
default:
assert(0 && "Invalid Edge");
break;
}
if (stop) {
// Exiting boundary to enter interior.
contour_line.push_back(edge_interp(quad_edge,
level_index == 1 ? lower_level
: upper_level));
break;
}
move_to_next_boundary_edge(quad_edge);
// Just moved to new quad edge, so label parent of start of quad edge.
switch (quad_edge.edge) {
case Edge_W:
case Edge_SW:
case Edge_S:
case Edge_SE:
if (!EXISTS_SE_CORNER(quad))
_parent_cache.set_parent(quad, contour_line);
break;
case Edge_E:
case Edge_NE:
case Edge_N:
case Edge_NW:
if (!EXISTS_SW_CORNER(quad))
_parent_cache.set_parent(quad + 1, contour_line);
break;
default:
assert(0 && "Invalid edge");
break;
}
// Add point to contour.
contour_line.push_back(get_point_xy(end_point));
if (first_edge)
first_edge = false;
}
return level_index;
}
void QuadContourGenerator::follow_interior(ContourLine& contour_line,
QuadEdge& quad_edge,
unsigned int level_index,
const double& level,
bool want_initial_point,
const QuadEdge* start_quad_edge,
unsigned int start_level_index,
bool set_parents)
{
assert(quad_edge.quad >= 0 && quad_edge.quad < _n &&
"Quad index out of bounds.");
assert(quad_edge.edge != Edge_None && "Invalid edge");
assert((level_index == 1 || level_index == 2) &&
"level index must be 1 or 2");
assert((start_quad_edge == 0 ||
(start_quad_edge->quad >= 0 && start_quad_edge->quad < _n)) &&
"Start quad index out of bounds.");
assert((start_quad_edge == 0 || start_quad_edge->edge != Edge_None) &&
"Invalid start edge");
assert((start_level_index == 1 || start_level_index == 2) &&
"start level index must be 1 or 2");
long& quad = quad_edge.quad;
Edge& edge = quad_edge.edge;
if (want_initial_point)
contour_line.push_back(edge_interp(quad_edge, level));
CacheItem visited_mask = (level_index == 1 ? MASK_VISITED_1 : MASK_VISITED_2);
CacheItem saddle_mask = (level_index == 1 ? MASK_SADDLE_1 : MASK_SADDLE_2);
Dir dir = Dir_Straight;
while (true) {
assert(!EXISTS_NONE(quad) && "Quad does not exist");
assert(!(_cache[quad] & visited_mask) && "Quad already visited");
// Determine direction to move to next quad. If the quad is already
// labelled as a saddle quad then the direction is easily read from
// the cache. Otherwise the direction is determined differently
// depending on whether the quad is a corner quad or not.
if (_cache[quad] & saddle_mask) {
// Already identified as a saddle quad, so direction is easy.
dir = (SADDLE_LEFT(quad,level_index) ? Dir_Left : Dir_Right);
_cache[quad] |= visited_mask;
}
else if (EXISTS_ANY_CORNER(quad)) {
// Need z-level of point opposite the entry edge, as that
// determines whether contour turns left or right.
long point_opposite = -1;
switch (edge) {
case Edge_E:
point_opposite = (EXISTS_SE_CORNER(quad) ? POINT_SW
: POINT_NW);
break;
case Edge_N:
point_opposite = (EXISTS_NW_CORNER(quad) ? POINT_SW
: POINT_SE);
break;
case Edge_W:
point_opposite = (EXISTS_SW_CORNER(quad) ? POINT_SE
: POINT_NE);
break;
case Edge_S:
point_opposite = (EXISTS_SW_CORNER(quad) ? POINT_NW
: POINT_NE);
break;
case Edge_NE: point_opposite = POINT_SW; break;
case Edge_NW: point_opposite = POINT_SE; break;
case Edge_SW: point_opposite = POINT_NE; break;
case Edge_SE: point_opposite = POINT_NW; break;
default: assert(0 && "Invalid edge"); break;
}
assert(point_opposite != -1 && "Failed to find opposite point");
// Lower-level polygons (level_index == 1) always have higher
// values to the left of the contour. Upper-level contours
// (level_index == 2) are reversed, which is what the fancy XOR
// does below.
if ((Z_LEVEL(point_opposite) >= level_index) ^ (level_index == 2))
dir = Dir_Right;
else
dir = Dir_Left;
_cache[quad] |= visited_mask;
}
else {
// Calculate configuration of this quad.
long point_left = -1, point_right = -1;
switch (edge) {
case Edge_E: point_left = POINT_SW; point_right = POINT_NW; break;
case Edge_N: point_left = POINT_SE; point_right = POINT_SW; break;
case Edge_W: point_left = POINT_NE; point_right = POINT_SE; break;
case Edge_S: point_left = POINT_NW; point_right = POINT_NE; break;
default: assert(0 && "Invalid edge"); break;
}
unsigned int config = (Z_LEVEL(point_left) >= level_index) << 1 |
(Z_LEVEL(point_right) >= level_index);
// Upper level (level_index == 2) polygons are reversed compared to
// lower level ones, i.e. higher values on the right rather than
// the left.
if (level_index == 2)
config = 3 - config;
// Calculate turn direction to move to next quad along contour line.
if (config == 1) {
// New saddle quad, set up cache bits for it.
double zmid = 0.25*(get_point_z(POINT_SW) +
get_point_z(POINT_SE) +
get_point_z(POINT_NW) +
get_point_z(POINT_NE));
_cache[quad] |= (level_index == 1 ? MASK_SADDLE_1 : MASK_SADDLE_2);
if ((zmid > level) ^ (level_index == 2)) {
dir = Dir_Right;
}
else {
dir = Dir_Left;
_cache[quad] |= (level_index == 1 ? MASK_SADDLE_LEFT_1
: MASK_SADDLE_LEFT_2);
}
if (edge == Edge_N || edge == Edge_E) {
// Next visit to this quad must start on S or W.
_cache[quad] |= (level_index == 1 ? MASK_SADDLE_START_SW_1
: MASK_SADDLE_START_SW_2);
}
}
else {
// Normal (non-saddle) quad.
dir = (config == 0 ? Dir_Left
: (config == 3 ? Dir_Right : Dir_Straight));
_cache[quad] |= visited_mask;
}
}
// Use dir to determine exit edge.
edge = get_exit_edge(quad_edge, dir);
if (set_parents) {
if (edge == Edge_E)
_parent_cache.set_parent(quad+1, contour_line);
else if (edge == Edge_W)
_parent_cache.set_parent(quad, contour_line);
}
// Add new point to contour line.
contour_line.push_back(edge_interp(quad_edge, level));
// Stop if reached boundary.
if (is_edge_a_boundary(quad_edge))
break;
move_to_next_quad(quad_edge);
assert(quad_edge.quad >= 0 && quad_edge.quad < _n &&
"Quad index out of bounds");
// Return if reached start point of contour line.
if (start_quad_edge != 0 &&
quad_edge == *start_quad_edge &&
level_index == start_level_index)
break;
}
}
void QuadContourGenerator::get_chunk_limits(long ijchunk,
long& ichunk,
long& jchunk,
long& istart,
long& iend,
long& jstart,
long& jend)
{
assert(ijchunk >= 0 && ijchunk < _chunk_count && "ijchunk out of bounds");
ichunk = ijchunk % _nxchunk;
jchunk = ijchunk / _nxchunk;
istart = ichunk*_chunk_size;
iend = (ichunk == _nxchunk-1 ? _nx : (ichunk+1)*_chunk_size);
jstart = jchunk*_chunk_size;
jend = (jchunk == _nychunk-1 ? _ny : (jchunk+1)*_chunk_size);
}
Edge QuadContourGenerator::get_corner_start_edge(long quad,
unsigned int level_index) const
{
assert(quad >= 0 && quad < _n && "Quad index out of bounds");
assert((level_index == 1 || level_index == 2) &&
"level index must be 1 or 2");
assert(EXISTS_ANY_CORNER(quad) && "Quad is not a corner");
// Diagram for NE corner. Rotate for other corners.
//
// edge12
// point1 +---------+ point2
// \ |
// \ | edge23
// edge31 \ |
// \ |
// + point3
//
long point1, point2, point3;
Edge edge12, edge23, edge31;
switch (_cache[quad] & MASK_EXISTS) {
case MASK_EXISTS_SW_CORNER:
point1 = POINT_SE; point2 = POINT_SW; point3 = POINT_NW;
edge12 = Edge_S; edge23 = Edge_W; edge31 = Edge_NE;
break;
case MASK_EXISTS_SE_CORNER:
point1 = POINT_NE; point2 = POINT_SE; point3 = POINT_SW;
edge12 = Edge_E; edge23 = Edge_S; edge31 = Edge_NW;
break;
case MASK_EXISTS_NW_CORNER:
point1 = POINT_SW; point2 = POINT_NW; point3 = POINT_NE;
edge12 = Edge_W; edge23 = Edge_N; edge31 = Edge_SE;
break;
case MASK_EXISTS_NE_CORNER:
point1 = POINT_NW; point2 = POINT_NE; point3 = POINT_SE;
edge12 = Edge_N; edge23 = Edge_E; edge31 = Edge_SW;
break;
default:
assert(0 && "Invalid EXISTS for quad");
return Edge_None;
}
unsigned int config = (Z_LEVEL(point1) >= level_index) << 2 |
(Z_LEVEL(point2) >= level_index) << 1 |
(Z_LEVEL(point3) >= level_index);
// Upper level (level_index == 2) polygons are reversed compared to lower
// level ones, i.e. higher values on the right rather than the left.
if (level_index == 2)
config = 7 - config;
switch (config) {
case 0: return Edge_None;
case 1: return edge23;
case 2: return edge12;
case 3: return edge12;
case 4: return edge31;
case 5: return edge23;
case 6: return edge31;
case 7: return Edge_None;
default: assert(0 && "Invalid config"); return Edge_None;
}
}
long QuadContourGenerator::get_edge_point_index(const QuadEdge& quad_edge,
bool start) const
{
assert(quad_edge.quad >= 0 && quad_edge.quad < _n &&
"Quad index out of bounds");
assert(quad_edge.edge != Edge_None && "Invalid edge");
// Edges are ordered anticlockwise around their quad, as indicated by
// directions of arrows in diagrams below.
// Full quad NW corner (others similar)
//
// POINT_NW Edge_N POINT_NE POINT_NW Edge_N POINT_NE
// +----<-----+ +----<-----+
// | | | /
// | | | quad /
// Edge_W V quad ^ Edge_E Edge_W V ^
// | | | / Edge_SE
// | | | /
// +---->-----+ +
// POINT_SW Edge_S POINT_SE POINT_SW
//
const long& quad = quad_edge.quad;
switch (quad_edge.edge) {
case Edge_E: return (start ? POINT_SE : POINT_NE);
case Edge_N: return (start ? POINT_NE : POINT_NW);
case Edge_W: return (start ? POINT_NW : POINT_SW);
case Edge_S: return (start ? POINT_SW : POINT_SE);
case Edge_NE: return (start ? POINT_SE : POINT_NW);
case Edge_NW: return (start ? POINT_NE : POINT_SW);
case Edge_SW: return (start ? POINT_NW : POINT_SE);
case Edge_SE: return (start ? POINT_SW : POINT_NE);
default: assert(0 && "Invalid edge"); return 0;
}
}
Edge QuadContourGenerator::get_exit_edge(const QuadEdge& quad_edge,
Dir dir) const
{
assert(quad_edge.quad >= 0 && quad_edge.quad < _n &&
"Quad index out of bounds");
assert(quad_edge.edge != Edge_None && "Invalid edge");
const long& quad = quad_edge.quad;
const Edge& edge = quad_edge.edge;
if (EXISTS_ANY_CORNER(quad)) {
// Corner directions are always left or right. A corner is a triangle,
// entered via one edge so the other two edges are the left and right
// ones.
switch (edge) {
case Edge_E:
return (EXISTS_SE_CORNER(quad)
? (dir == Dir_Left ? Edge_S : Edge_NW)
: (dir == Dir_Right ? Edge_N : Edge_SW));
case Edge_N:
return (EXISTS_NW_CORNER(quad)
? (dir == Dir_Right ? Edge_W : Edge_SE)
: (dir == Dir_Left ? Edge_E : Edge_SW));
case Edge_W:
return (EXISTS_SW_CORNER(quad)
? (dir == Dir_Right ? Edge_S : Edge_NE)
: (dir == Dir_Left ? Edge_N : Edge_SE));
case Edge_S:
return (EXISTS_SW_CORNER(quad)
? (dir == Dir_Left ? Edge_W : Edge_NE)
: (dir == Dir_Right ? Edge_E : Edge_NW));
case Edge_NE: return (dir == Dir_Left ? Edge_S : Edge_W);
case Edge_NW: return (dir == Dir_Left ? Edge_E : Edge_S);
case Edge_SW: return (dir == Dir_Left ? Edge_N : Edge_E);
case Edge_SE: return (dir == Dir_Left ? Edge_W : Edge_N);
default: assert(0 && "Invalid edge"); return Edge_None;
}
}
else {
// A full quad has four edges, entered via one edge so that other three
// edges correspond to left, straight and right directions.
switch (edge) {
case Edge_E:
return (dir == Dir_Left ? Edge_S :
(dir == Dir_Right ? Edge_N : Edge_W));
case Edge_N:
return (dir == Dir_Left ? Edge_E :
(dir == Dir_Right ? Edge_W : Edge_S));
case Edge_W:
return (dir == Dir_Left ? Edge_N :
(dir == Dir_Right ? Edge_S : Edge_E));
case Edge_S:
return (dir == Dir_Left ? Edge_W :
(dir == Dir_Right ? Edge_E : Edge_N));
default: assert(0 && "Invalid edge"); return Edge_None;
}
}
}
XY QuadContourGenerator::get_point_xy(long point) const
{
assert(point >= 0 && point < _n && "Point index out of bounds.");
return XY(_x.data()[static_cast<npy_intp>(point)],
_y.data()[static_cast<npy_intp>(point)]);
}
const double& QuadContourGenerator::get_point_z(long point) const
{
assert(point >= 0 && point < _n && "Point index out of bounds.");
return _z.data()[static_cast<npy_intp>(point)];
}
Edge QuadContourGenerator::get_quad_start_edge(long quad,
unsigned int level_index) const
{
assert(quad >= 0 && quad < _n && "Quad index out of bounds");
assert((level_index == 1 || level_index == 2) &&
"level index must be 1 or 2");
assert(EXISTS_QUAD(quad) && "Quad does not exist");
unsigned int config = (Z_NW >= level_index) << 3 |
(Z_NE >= level_index) << 2 |
(Z_SW >= level_index) << 1 |
(Z_SE >= level_index);
// Upper level (level_index == 2) polygons are reversed compared to lower
// level ones, i.e. higher values on the right rather than the left.
if (level_index == 2)
config = 15 - config;
switch (config) {
case 0: return Edge_None;
case 1: return Edge_E;
case 2: return Edge_S;
case 3: return Edge_E;
case 4: return Edge_N;
case 5: return Edge_N;
case 6:
// If already identified as a saddle quad then the start edge is
// read from the cache. Otherwise return either valid start edge
// and the subsequent call to follow_interior() will correctly set
// up saddle bits in cache.
if (!SADDLE(quad,level_index) || SADDLE_START_SW(quad,level_index))
return Edge_S;
else
return Edge_N;
case 7: return Edge_N;
case 8: return Edge_W;
case 9:
// See comment for 6 above.
if (!SADDLE(quad,level_index) || SADDLE_START_SW(quad,level_index))
return Edge_W;
else
return Edge_E;
case 10: return Edge_S;
case 11: return Edge_E;
case 12: return Edge_W;
case 13: return Edge_W;
case 14: return Edge_S;
case 15: return Edge_None;
default: assert(0 && "Invalid config"); return Edge_None;
}
}
Edge QuadContourGenerator::get_start_edge(long quad,
unsigned int level_index) const
{
if (EXISTS_ANY_CORNER(quad))
return get_corner_start_edge(quad, level_index);
else
return get_quad_start_edge(quad, level_index);
}
void QuadContourGenerator::init_cache_grid(const MaskArray& mask)
{
long i, j, quad;
if (mask.empty()) {
// No mask, easy to calculate quad existence and boundaries together.
quad = 0;
for (j = 0; j < _ny; ++j) {
for (i = 0; i < _nx; ++i, ++quad) {
_cache[quad] = 0;
if (i < _nx-1 && j < _ny-1)
_cache[quad] |= MASK_EXISTS_QUAD;
if ((i % _chunk_size == 0 || i == _nx-1) && j < _ny-1)
_cache[quad] |= MASK_BOUNDARY_W;
if ((j % _chunk_size == 0 || j == _ny-1) && i < _nx-1)
_cache[quad] |= MASK_BOUNDARY_S;
}
}
}
else {
// Casting avoids problem when sizeof(bool) != sizeof(npy_bool).
const npy_bool* mask_ptr =
reinterpret_cast<const npy_bool*>(mask.data());
// Have mask so use two stages.
// Stage 1, determine if quads/corners exist.
quad = 0;
for (j = 0; j < _ny; ++j) {
for (i = 0; i < _nx; ++i, ++quad) {
_cache[quad] = 0;
if (i < _nx-1 && j < _ny-1) {
unsigned int config = mask_ptr[POINT_NW] << 3 |
mask_ptr[POINT_NE] << 2 |
mask_ptr[POINT_SW] << 1 |
mask_ptr[POINT_SE];
if (_corner_mask) {
switch (config) {
case 0: _cache[quad] = MASK_EXISTS_QUAD; break;
case 1: _cache[quad] = MASK_EXISTS_NW_CORNER; break;
case 2: _cache[quad] = MASK_EXISTS_NE_CORNER; break;
case 4: _cache[quad] = MASK_EXISTS_SW_CORNER; break;
case 8: _cache[quad] = MASK_EXISTS_SE_CORNER; break;
default:
// Do nothing, quad is masked out.
break;
}
}
else if (config == 0)
_cache[quad] = MASK_EXISTS_QUAD;
}
}
}
// Stage 2, calculate W and S boundaries. For each quad use boundary
// data already calculated for quads to W and S, so must iterate
// through quads in correct order (increasing i and j indices).
// Cannot use boundary data for quads to E and N as have not yet
// calculated it.
quad = 0;
for (j = 0; j < _ny; ++j) {
for (i = 0; i < _nx; ++i, ++quad) {
if (_corner_mask) {
bool W_exists_none = (i == 0 || EXISTS_NONE(quad-1));
bool S_exists_none = (j == 0 || EXISTS_NONE(quad-_nx));
bool W_exists_E_edge = (i > 0 && EXISTS_E_EDGE(quad-1));
bool S_exists_N_edge = (j > 0 && EXISTS_N_EDGE(quad-_nx));
if ((EXISTS_W_EDGE(quad) && W_exists_none) ||
(EXISTS_NONE(quad) && W_exists_E_edge) ||
(i % _chunk_size == 0 && EXISTS_W_EDGE(quad) &&
W_exists_E_edge))
_cache[quad] |= MASK_BOUNDARY_W;
if ((EXISTS_S_EDGE(quad) && S_exists_none) ||
(EXISTS_NONE(quad) && S_exists_N_edge) ||
(j % _chunk_size == 0 && EXISTS_S_EDGE(quad) &&
S_exists_N_edge))
_cache[quad] |= MASK_BOUNDARY_S;
}
else {
bool W_exists_quad = (i > 0 && EXISTS_QUAD(quad-1));
bool S_exists_quad = (j > 0 && EXISTS_QUAD(quad-_nx));
if ((EXISTS_QUAD(quad) != W_exists_quad) ||
(i % _chunk_size == 0 && EXISTS_QUAD(quad) &&
W_exists_quad))
_cache[quad] |= MASK_BOUNDARY_W;
if ((EXISTS_QUAD(quad) != S_exists_quad) ||
(j % _chunk_size == 0 && EXISTS_QUAD(quad) &&
S_exists_quad))
_cache[quad] |= MASK_BOUNDARY_S;
}
}
}
}
}
void QuadContourGenerator::init_cache_levels(const double& lower_level,
const double& upper_level)
{
assert(upper_level >= lower_level &&
"upper and lower levels are wrong way round");
bool two_levels = (lower_level != upper_level);
CacheItem keep_mask =
(_corner_mask ? MASK_EXISTS | MASK_BOUNDARY_S | MASK_BOUNDARY_W
: MASK_EXISTS_QUAD | MASK_BOUNDARY_S | MASK_BOUNDARY_W);
if (two_levels) {
const double* z_ptr = _z.data();
for (long quad = 0; quad < _n; ++quad, ++z_ptr) {
_cache[quad] &= keep_mask;
if (*z_ptr > upper_level)
_cache[quad] |= MASK_Z_LEVEL_2;
else if (*z_ptr > lower_level)
_cache[quad] |= MASK_Z_LEVEL_1;
}
}
else {
const double* z_ptr = _z.data();
for (long quad = 0; quad < _n; ++quad, ++z_ptr) {
_cache[quad] &= keep_mask;
if (*z_ptr > lower_level)
_cache[quad] |= MASK_Z_LEVEL_1;
}
}
}
XY QuadContourGenerator::interp(
long point1, long point2, const double& level) const
{
assert(point1 >= 0 && point1 < _n && "Point index 1 out of bounds.");
assert(point2 >= 0 && point2 < _n && "Point index 2 out of bounds.");
assert(point1 != point2 && "Identical points");
double fraction = (get_point_z(point2) - level) /
(get_point_z(point2) - get_point_z(point1));
return get_point_xy(point1)*fraction + get_point_xy(point2)*(1.0 - fraction);
}
bool QuadContourGenerator::is_edge_a_boundary(const QuadEdge& quad_edge) const
{
assert(quad_edge.quad >= 0 && quad_edge.quad < _n &&
"Quad index out of bounds");
assert(quad_edge.edge != Edge_None && "Invalid edge");
switch (quad_edge.edge) {
case Edge_E: return BOUNDARY_E(quad_edge.quad);
case Edge_N: return BOUNDARY_N(quad_edge.quad);
case Edge_W: return BOUNDARY_W(quad_edge.quad);
case Edge_S: return BOUNDARY_S(quad_edge.quad);
case Edge_NE: return EXISTS_SW_CORNER(quad_edge.quad);
case Edge_NW: return EXISTS_SE_CORNER(quad_edge.quad);
case Edge_SW: return EXISTS_NE_CORNER(quad_edge.quad);
case Edge_SE: return EXISTS_NW_CORNER(quad_edge.quad);
default: assert(0 && "Invalid edge"); return true;
}
}
void QuadContourGenerator::move_to_next_boundary_edge(QuadEdge& quad_edge) const
{
assert(is_edge_a_boundary(quad_edge) && "QuadEdge is not a boundary");
long& quad = quad_edge.quad;
Edge& edge = quad_edge.edge;
quad = get_edge_point_index(quad_edge, false);
// quad is now such that POINT_SW is the end point of the quad_edge passed
// to this function.
// To find the next boundary edge, first attempt to turn left 135 degrees
// and if that edge is a boundary then move to it. If not, attempt to turn
// left 90 degrees, then left 45 degrees, then straight on, etc, until can
// move.
// First determine which edge to attempt first.
int index = 0;
switch (edge) {
case Edge_E: index = 0; break;
case Edge_SE: index = 1; break;
case Edge_S: index = 2; break;
case Edge_SW: index = 3; break;
case Edge_W: index = 4; break;
case Edge_NW: index = 5; break;
case Edge_N: index = 6; break;
case Edge_NE: index = 7; break;
default: assert(0 && "Invalid edge"); break;
}
// If _corner_mask not set, only need to consider odd index in loop below.
if (!_corner_mask)
++index;
// Try each edge in turn until a boundary is found.
int start_index = index;
do
{
switch (index) {
case 0:
if (EXISTS_SE_CORNER(quad-_nx-1)) { // Equivalent to BOUNDARY_NW
quad -= _nx+1;
edge = Edge_NW;
return;
}
break;
case 1:
if (BOUNDARY_N(quad-_nx-1)) {
quad -= _nx+1;
edge = Edge_N;
return;
}
break;
case 2:
if (EXISTS_SW_CORNER(quad-1)) { // Equivalent to BOUNDARY_NE
quad -= 1;
edge = Edge_NE;
return;
}
break;
case 3:
if (BOUNDARY_E(quad-1)) {
quad -= 1;
edge = Edge_E;
return;
}
break;
case 4:
if (EXISTS_NW_CORNER(quad)) { // Equivalent to BOUNDARY_SE
edge = Edge_SE;
return;
}
break;
case 5:
if (BOUNDARY_S(quad)) {
edge = Edge_S;
return;
}
break;
case 6:
if (EXISTS_NE_CORNER(quad-_nx)) { // Equivalent to BOUNDARY_SW
quad -= _nx;
edge = Edge_SW;
return;
}
break;
case 7:
if (BOUNDARY_W(quad-_nx)) {
quad -= _nx;
edge = Edge_W;
return;
}
break;
default: assert(0 && "Invalid index"); break;
}
if (_corner_mask)
index = (index + 1) % 8;
else
index = (index + 2) % 8;
} while (index != start_index);
assert(0 && "Failed to find next boundary edge");
}
void QuadContourGenerator::move_to_next_quad(QuadEdge& quad_edge) const
{
assert(quad_edge.quad >= 0 && quad_edge.quad < _n &&
"Quad index out of bounds");
assert(quad_edge.edge != Edge_None && "Invalid edge");
// Move from quad_edge.quad to the neighbouring quad in the direction
// specified by quad_edge.edge.
switch (quad_edge.edge) {
case Edge_E: quad_edge.quad += 1; quad_edge.edge = Edge_W; break;
case Edge_N: quad_edge.quad += _nx; quad_edge.edge = Edge_S; break;
case Edge_W: quad_edge.quad -= 1; quad_edge.edge = Edge_E; break;
case Edge_S: quad_edge.quad -= _nx; quad_edge.edge = Edge_N; break;
default: assert(0 && "Invalid edge"); break;
}
}
void QuadContourGenerator::single_quad_filled(Contour& contour,
long quad,
const double& lower_level,
const double& upper_level)
{
assert(quad >= 0 && quad < _n && "Quad index out of bounds");
// Order of checking is important here as can have different ContourLines
// from both lower and upper levels in the same quad. First check the S
// edge, then move up the quad to the N edge checking as required.
// Possible starts from S boundary.
if (BOUNDARY_S(quad) && EXISTS_S_EDGE(quad)) {
// Lower-level start from S boundary into interior.
if (!VISITED_S(quad) && Z_SW >= 1 && Z_SE == 0)
contour.push_back(start_filled(quad, Edge_S, 1, NotHole, Interior,
lower_level, upper_level));
// Upper-level start from S boundary into interior.
if (!VISITED_S(quad) && Z_SW < 2 && Z_SE == 2)
contour.push_back(start_filled(quad, Edge_S, 2, NotHole, Interior,
lower_level, upper_level));
// Lower-level start following S boundary from W to E.
if (!VISITED_S(quad) && Z_SW <= 1 && Z_SE == 1)
contour.push_back(start_filled(quad, Edge_S, 1, NotHole, Boundary,
lower_level, upper_level));
// Upper-level start following S boundary from W to E.
if (!VISITED_S(quad) && Z_SW == 2 && Z_SE == 1)
contour.push_back(start_filled(quad, Edge_S, 2, NotHole, Boundary,
lower_level, upper_level));
}
// Possible starts from W boundary.
if (BOUNDARY_W(quad) && EXISTS_W_EDGE(quad)) {
// Lower-level start from W boundary into interior.
if (!VISITED_W(quad) && Z_NW >= 1 && Z_SW == 0)
contour.push_back(start_filled(quad, Edge_W, 1, NotHole, Interior,
lower_level, upper_level));
// Upper-level start from W boundary into interior.
if (!VISITED_W(quad) && Z_NW < 2 && Z_SW == 2)
contour.push_back(start_filled(quad, Edge_W, 2, NotHole, Interior,
lower_level, upper_level));
// Lower-level start following W boundary from N to S.
if (!VISITED_W(quad) && Z_NW <= 1 && Z_SW == 1)
contour.push_back(start_filled(quad, Edge_W, 1, NotHole, Boundary,
lower_level, upper_level));
// Upper-level start following W boundary from N to S.
if (!VISITED_W(quad) && Z_NW == 2 && Z_SW == 1)
contour.push_back(start_filled(quad, Edge_W, 2, NotHole, Boundary,
lower_level, upper_level));
}
// Possible starts from NE boundary.
if (EXISTS_SW_CORNER(quad)) { // i.e. BOUNDARY_NE
// Lower-level start following NE boundary from SE to NW, hole.
if (!VISITED_CORNER(quad) && Z_NW == 1 && Z_SE == 1)
contour.push_back(start_filled(quad, Edge_NE, 1, Hole, Boundary,
lower_level, upper_level));
}
// Possible starts from SE boundary.
else if (EXISTS_NW_CORNER(quad)) { // i.e. BOUNDARY_SE
// Lower-level start from N to SE.
if (!VISITED(quad,1) && Z_NW == 0 && Z_SW == 0 && Z_NE >= 1)
contour.push_back(start_filled(quad, Edge_N, 1, NotHole, Interior,
lower_level, upper_level));
// Upper-level start from SE to N, hole.
if (!VISITED(quad,2) && Z_NW < 2 && Z_SW < 2 && Z_NE == 2)
contour.push_back(start_filled(quad, Edge_SE, 2, Hole, Interior,
lower_level, upper_level));
// Upper-level start from N to SE.
if (!VISITED(quad,2) && Z_NW == 2 && Z_SW == 2 && Z_NE < 2)
contour.push_back(start_filled(quad, Edge_N, 2, NotHole, Interior,
lower_level, upper_level));
// Lower-level start from SE to N, hole.
if (!VISITED(quad,1) && Z_NW >= 1 && Z_SW >= 1 && Z_NE == 0)
contour.push_back(start_filled(quad, Edge_SE, 1, Hole, Interior,
lower_level, upper_level));
}
// Possible starts from NW boundary.
else if (EXISTS_SE_CORNER(quad)) { // i.e. BOUNDARY_NW
// Lower-level start from NW to E.
if (!VISITED(quad,1) && Z_SW == 0 && Z_SE == 0 && Z_NE >= 1)
contour.push_back(start_filled(quad, Edge_NW, 1, NotHole, Interior,
lower_level, upper_level));
// Upper-level start from E to NW, hole.
if (!VISITED(quad,2) && Z_SW < 2 && Z_SE < 2 && Z_NE == 2)
contour.push_back(start_filled(quad, Edge_E, 2, Hole, Interior,
lower_level, upper_level));
// Upper-level start from NW to E.
if (!VISITED(quad,2) && Z_SW == 2 && Z_SE == 2 && Z_NE < 2)
contour.push_back(start_filled(quad, Edge_NW, 2, NotHole, Interior,
lower_level, upper_level));
// Lower-level start from E to NW, hole.
if (!VISITED(quad,1) && Z_SW >= 1 && Z_SE >= 1 && Z_NE == 0)
contour.push_back(start_filled(quad, Edge_E, 1, Hole, Interior,
lower_level, upper_level));
}
// Possible starts from SW boundary.
else if (EXISTS_NE_CORNER(quad)) { // i.e. BOUNDARY_SW
// Lower-level start from SW boundary into interior.
if (!VISITED_CORNER(quad) && Z_NW >= 1 && Z_SE == 0)
contour.push_back(start_filled(quad, Edge_SW, 1, NotHole, Interior,
lower_level, upper_level));
// Upper-level start from SW boundary into interior.
if (!VISITED_CORNER(quad) && Z_NW < 2 && Z_SE == 2)
contour.push_back(start_filled(quad, Edge_SW, 2, NotHole, Interior,
lower_level, upper_level));
// Lower-level start following SW boundary from NW to SE.
if (!VISITED_CORNER(quad) && Z_NW <= 1 && Z_SE == 1)
contour.push_back(start_filled(quad, Edge_SW, 1, NotHole, Boundary,
lower_level, upper_level));
// Upper-level start following SW boundary from NW to SE.
if (!VISITED_CORNER(quad) && Z_NW == 2 && Z_SE == 1)
contour.push_back(start_filled(quad, Edge_SW, 2, NotHole, Boundary,
lower_level, upper_level));
}
// A full (unmasked) quad can only have a start on the NE corner, i.e. from
// N to E (lower level) or E to N (upper level). Any other start will have
// already been created in a call to this function for a prior quad so we
// don't need to test for it again here.
//
// The situation is complicated by the possibility that the quad is a
// saddle quad, in which case a contour line starting on the N could leave
// by either the W or the E. We only need to consider those leaving E.
//
// A NE corner can also have a N to E or E to N start.
if (EXISTS_QUAD(quad) || EXISTS_NE_CORNER(quad)) {
// Lower-level start from N to E.
if (!VISITED(quad,1) && Z_NW == 0 && Z_SE == 0 && Z_NE >= 1 &&
(!SADDLE(quad,1) || SADDLE_LEFT(quad,1)))
contour.push_back(start_filled(quad, Edge_N, 1, NotHole, Interior,
lower_level, upper_level));
// Upper-level start from E to N, hole.
if (!VISITED(quad,2) && Z_NW < 2 && Z_SE < 2 && Z_NE == 2 &&
(!SADDLE(quad,2) || !SADDLE_LEFT(quad,2)))
contour.push_back(start_filled(quad, Edge_E, 2, Hole, Interior,
lower_level, upper_level));
// Upper-level start from N to E.
if (!VISITED(quad,2) && Z_NW == 2 && Z_SE == 2 && Z_NE < 2 &&
(!SADDLE(quad,2) || SADDLE_LEFT(quad,2)))
contour.push_back(start_filled(quad, Edge_N, 2, NotHole, Interior,
lower_level, upper_level));
// Lower-level start from E to N, hole.
if (!VISITED(quad,1) && Z_NW >= 1 && Z_SE >= 1 && Z_NE == 0 &&
(!SADDLE(quad,1) || !SADDLE_LEFT(quad,1)))
contour.push_back(start_filled(quad, Edge_E, 1, Hole, Interior,
lower_level, upper_level));
// All possible contours passing through the interior of this quad
// should have already been created, so assert this.
assert((VISITED(quad,1) || get_start_edge(quad, 1) == Edge_None) &&
"Found start of contour that should have already been created");
assert((VISITED(quad,2) || get_start_edge(quad, 2) == Edge_None) &&
"Found start of contour that should have already been created");
}
// Lower-level start following N boundary from E to W, hole.
// This is required for an internal masked region which is a hole in a
// surrounding contour line.
if (BOUNDARY_N(quad) && EXISTS_N_EDGE(quad) &&
!VISITED_S(quad+_nx) && Z_NW == 1 && Z_NE == 1)
contour.push_back(start_filled(quad, Edge_N, 1, Hole, Boundary,
lower_level, upper_level));
}
ContourLine* QuadContourGenerator::start_filled(
long quad,
Edge edge,
unsigned int start_level_index,
HoleOrNot hole_or_not,
BoundaryOrInterior boundary_or_interior,
const double& lower_level,
const double& upper_level)
{
assert(quad >= 0 && quad < _n && "Quad index out of bounds");
assert(edge != Edge_None && "Invalid edge");
assert((start_level_index == 1 || start_level_index == 2) &&
"start level index must be 1 or 2");
ContourLine* contour_line = new ContourLine(hole_or_not == Hole);
if (hole_or_not == Hole) {
// Find and set parent ContourLine.
ContourLine* parent = _parent_cache.get_parent(quad + 1);
assert(parent != 0 && "Failed to find parent ContourLine");
contour_line->set_parent(parent);
parent->add_child(contour_line);
}
QuadEdge quad_edge(quad, edge);
const QuadEdge start_quad_edge(quad_edge);
unsigned int level_index = start_level_index;
// If starts on interior, can only finish on interior.
// If starts on boundary, can only finish on boundary.
while (true) {
if (boundary_or_interior == Interior) {
double level = (level_index == 1 ? lower_level : upper_level);
follow_interior(*contour_line, quad_edge, level_index, level,
false, &start_quad_edge, start_level_index, true);
}
else {
level_index = follow_boundary(
*contour_line, quad_edge, lower_level,
upper_level, level_index, start_quad_edge);
}
if (quad_edge == start_quad_edge && (boundary_or_interior == Boundary ||
level_index == start_level_index))
break;
if (boundary_or_interior == Boundary)
boundary_or_interior = Interior;
else
boundary_or_interior = Boundary;
}
return contour_line;
}
bool QuadContourGenerator::start_line(
PyObject* vertices_list, long quad, Edge edge, const double& level)
{
assert(vertices_list != 0 && "Null python vertices list");
assert(is_edge_a_boundary(QuadEdge(quad, edge)) &&
"QuadEdge is not a boundary");
QuadEdge quad_edge(quad, edge);
ContourLine contour_line(false);
follow_interior(contour_line, quad_edge, 1, level, true, 0, 1, false);
append_contour_line_to_vertices(contour_line, vertices_list);
return VISITED(quad,1);
}
void QuadContourGenerator::write_cache(bool grid_only) const
{
std::cout << "-----------------------------------------------" << std::endl;
for (long quad = 0; quad < _n; ++quad)
write_cache_quad(quad, grid_only);
std::cout << "-----------------------------------------------" << std::endl;
}
void QuadContourGenerator::write_cache_quad(long quad, bool grid_only) const
{
long j = quad / _nx;
long i = quad - j*_nx;
std::cout << quad << ": i=" << i << " j=" << j
<< " EXISTS=" << EXISTS_QUAD(quad);
if (_corner_mask)
std::cout << " CORNER=" << EXISTS_SW_CORNER(quad) << EXISTS_SE_CORNER(quad)
<< EXISTS_NW_CORNER(quad) << EXISTS_NE_CORNER(quad);
std::cout << " BNDY=" << (BOUNDARY_S(quad)>0) << (BOUNDARY_W(quad)>0);
if (!grid_only) {
std::cout << " Z=" << Z_LEVEL(quad)
<< " SAD=" << (SADDLE(quad,1)>0) << (SADDLE(quad,2)>0)
<< " LEFT=" << (SADDLE_LEFT(quad,1)>0) << (SADDLE_LEFT(quad,2)>0)
<< " NW=" << (SADDLE_START_SW(quad,1)>0) << (SADDLE_START_SW(quad,2)>0)
<< " VIS=" << (VISITED(quad,1)>0) << (VISITED(quad,2)>0)
<< (VISITED_S(quad)>0) << (VISITED_W(quad)>0)
<< (VISITED_CORNER(quad)>0);
}
std::cout << std::endl;
}
