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Index: fenics-dolfinx/cpp/dolfinx/geometry/gjk.h
===================================================================
--- fenics-dolfinx.orig/cpp/dolfinx/geometry/gjk.h 2025-10-13 14:45:26.932905482 +0200
+++ fenics-dolfinx/cpp/dolfinx/geometry/gjk.h 2025-10-13 14:45:26.929096958 +0200
@@ -8,8 +8,8 @@
#include <algorithm>
#include <array>
+#include <boost/multiprecision/cpp_bin_float.hpp>
#include <concepts>
-#include <dolfinx/common/math.h>
#include <limits>
#include <numeric>
#include <span>
@@ -22,200 +22,245 @@
namespace impl_gjk
{
-/// @brief Find the resulting sub-simplex of the input simplex which is
-/// nearest to the origin. Also, return the shortest vector from the
-/// origin to the resulting simplex.
-template <std::floating_point T>
-std::pair<std::vector<T>, std::array<T, 3>>
-nearest_simplex(std::span<const T> s)
+/// @brief Determinant of 3x3 matrix A
+/// @param A 3x3 matrix
+/// @returns det(A)
+template <typename T>
+inline T det3(std::span<const T, 9> A)
+{
+ T w0 = A[3 + 1] * A[2 * 3 + 2] - A[3 + 2] * A[3 * 2 + 1];
+ T w1 = A[3] * A[3 * 2 + 2] - A[3 + 2] * A[3 * 2];
+ T w2 = A[3] * A[3 * 2 + 1] - A[3 + 1] * A[3 * 2];
+ return A[0] * w0 - A[1] * w1 + A[2] * w2;
+}
+
+/// @brief Dot product of vectors a and b, both size 3.
+/// @param a Vector of size 3
+/// @param b Vector of size 3
+/// @returns a.b
+template <typename Vec>
+inline Vec::value_type dot3(const Vec& a, const Vec& b)
+{
+ return a[0] * b[0] + a[1] * b[1] + a[2] * b[2];
+}
+
+/// @brief Find the barycentric coordinates in the simplex `s`, of the point in
+/// `s` which is closest to the origin.
+/// @param s Simplex described by a set of points in 3D, row-major, flattened.
+/// @return Barycentric coordinates of the point in s closest to the origin.
+/// @note `s` may be an interval, a triangle or a tetrahedron.
+template <typename T>
+std::vector<T> nearest_simplex(std::span<const T> s)
{
assert(s.size() % 3 == 0);
const std::size_t s_rows = s.size() / 3;
+
+ SPDLOG_DEBUG("GJK: nearest_simplex({})", s_rows);
+
switch (s_rows)
{
case 2:
{
+ // Simplex is an interval. Point may lie on the interval, or on either end.
// Compute lm = dot(s0, ds / |ds|)
- auto s0 = s.template subspan<0, 3>();
- auto s1 = s.template subspan<3, 3>();
- std::array ds = {s1[0] - s0[0], s1[1] - s0[1], s1[2] - s0[2]};
- const T lm = -(s0[0] * ds[0] + s0[1] * ds[1] + s0[2] * ds[2])
- / (ds[0] * ds[0] + ds[1] * ds[1] + ds[2] * ds[2]);
- if (lm >= 0.0 and lm <= 1.0)
- {
- // The origin is between A and B
- // v = s0 + lm * (s1 - s0);
- std::array v
- = {s0[0] + lm * ds[0], s0[1] + lm * ds[1], s0[2] + lm * ds[2]};
- return {std::vector<T>(s.begin(), s.end()), v};
- }
+ std::span<const T, 3> s0 = s.template subspan<0, 3>();
+ std::span<const T, 3> s1 = s.template subspan<3, 3>();
+ T lm = dot3(s0, s0) - dot3(s0, s1);
if (lm < 0.0)
- return {std::vector<T>(s0.begin(), s0.end()), {s0[0], s0[1], s0[2]}};
- else
- return {std::vector<T>(s1.begin(), s1.end()), {s1[0], s1[1], s1[2]}};
+ {
+ SPDLOG_DEBUG("GJK: line point A");
+ return {1.0, 0.0};
+ }
+ T mu = dot3(s1, s1) - dot3(s1, s0);
+ if (mu < 0.0)
+ {
+ SPDLOG_DEBUG("GJK: line point B");
+ return {0.0, 1.0};
+ }
+
+ SPDLOG_DEBUG("GJK line: AB");
+ T f1 = 1.0 / (lm + mu);
+ return {mu * f1, lm * f1};
}
case 3:
{
+ // Simplex is a triangle. Point may lie in one of 7 regions (outside near a
+ // vertex, outside near an edge, or on the interior)
auto a = s.template subspan<0, 3>();
auto b = s.template subspan<3, 3>();
auto c = s.template subspan<6, 3>();
- auto length = [](auto& x, auto& y)
+
+ T aa = dot3(a, a);
+ T ab = dot3(a, b);
+ T ac = dot3(a, c);
+ T d1 = aa - ab;
+ T d2 = aa - ac;
+ if (d1 < 0.0 and d2 < 0.0)
{
- return std::transform_reduce(x.begin(), x.end(), y.begin(), 0.0,
- std::plus{}, [](auto x, auto y)
- { return (x - y) * (x - y); });
- };
- const T ab2 = length(a, b);
- const T ac2 = length(a, c);
- const T bc2 = length(b, c);
-
- // Helper to compute dot(x, x - y)
- auto helper = [](auto& x, auto& y)
- {
- return std::transform_reduce(x.begin(), x.end(), y.begin(), 0.0,
- std::plus{},
- [](auto x, auto y) { return x * (x - y); });
- };
- const std::array lm
- = {helper(a, b) / ab2, helper(a, c) / ac2, helper(b, c) / bc2};
-
- T caba = 0;
- for (std::size_t i = 0; i < 3; ++i)
- caba += (c[i] - a[i]) * (b[i] - a[i]);
-
- // Calculate triangle ABC
- const T c2 = 1 - caba * caba / (ab2 * ac2);
- const T lbb = (lm[0] - lm[1] * caba / ab2) / c2;
- const T lcc = (lm[1] - lm[0] * caba / ac2) / c2;
-
- // Intersects triangle
- if (lbb >= 0.0 and lcc >= 0.0 and (lbb + lcc) <= 1.0)
- {
- // Calculate intersection more accurately
- // v = (c - a) x (b - a)
- std::array dx0 = {c[0] - a[0], c[1] - a[1], c[2] - a[2]};
- std::array dx1 = {b[0] - a[0], b[1] - a[1], b[2] - a[2]};
- std::array v = math::cross(dx0, dx1);
-
- // Barycentre of triangle
- std::array p = {(a[0] + b[0] + c[0]) / 3, (a[1] + b[1] + c[1]) / 3,
- (a[2] + b[2] + c[2]) / 3};
-
- T sum = v[0] * p[0] + v[1] * p[1] + v[2] * p[2];
- T vnorm2 = v[0] * v[0] + v[1] * v[1] + v[2] * v[2];
- for (std::size_t i = 0; i < 3; ++i)
- v[i] *= sum / vnorm2;
+ SPDLOG_DEBUG("GJK: Point A");
+ return {1.0, 0.0, 0.0};
+ }
- return {std::vector(s.begin(), s.end()), v};
+ T bb = dot3(b, b);
+ T bc = dot3(b, c);
+ T d3 = bb - ab;
+ T d4 = bb - bc;
+ if (d3 < 0.0 and d4 < 0.0)
+ {
+ SPDLOG_DEBUG("GJK: Point B");
+ return {0.0, 1.0, 0.0};
}
- // Get closest point
- std::size_t pos = 0;
+ T cc = dot3(c, c);
+ T d5 = cc - ac;
+ T d6 = cc - bc;
+ if (d5 < 0.0 and d6 < 0.0)
{
- T norm0 = std::numeric_limits<T>::max();
- for (std::size_t i = 0; i < s.size(); i += 3)
- {
- std::span<const T, 3> p(s.data() + i, 3);
- T norm = p[0] * p[0] + p[1] * p[1] + p[2] * p[2];
- if (norm < norm0)
- {
- pos = i / 3;
- norm0 = norm;
- }
- }
+ SPDLOG_DEBUG("GJK: Point C");
+ return {0.0, 0.0, 1.0};
}
- std::array vmin = {s[3 * pos], s[3 * pos + 1], s[3 * pos + 2]};
- T qmin = 0;
- for (std::size_t k = 0; k < 3; ++k)
- qmin += vmin[k] * vmin[k];
-
- std::vector smin = {vmin[0], vmin[1], vmin[2]};
-
- // Check if edges are closer
- constexpr int f[3][2] = {{0, 1}, {0, 2}, {1, 2}};
- for (std::size_t i = 0; i < s_rows; ++i)
- {
- auto s0 = s.subspan(3 * f[i][0], 3);
- auto s1 = s.subspan(3 * f[i][1], 3);
- if (lm[i] > 0 and lm[i] < 1)
- {
- std::array<T, 3> v;
- for (std::size_t k = 0; k < 3; ++k)
- v[k] = s0[k] + lm[i] * (s1[k] - s0[k]);
- T qnorm = 0;
- for (std::size_t k = 0; k < 3; ++k)
- qnorm += v[k] * v[k];
- if (qnorm < qmin)
- {
- std::ranges::copy(v, vmin.begin());
- qmin = qnorm;
- smin.resize(2 * 3);
- std::span<T, 3> smin0(smin.data(), 3);
- std::ranges::copy(s0, smin0.begin());
- std::span<T, 3> smin1(smin.data() + 3, 3);
- std::ranges::copy(s1, smin1.begin());
- }
- }
+ T vc = d4 * d1 - d1 * d3 + d3 * d2;
+ if (vc < 0.0 and d1 > 0.0 and d3 > 0.0)
+ {
+ SPDLOG_DEBUG("GJK: edge AB");
+ T f1 = 1.0 / (d1 + d3);
+ T lm = d1 * f1;
+ T mu = d3 * f1;
+ return {mu, lm, 0.0};
+ }
+ T vb = d1 * d5 - d5 * d2 + d2 * d6;
+ if (vb < 0.0 and d2 > 0.0 and d5 > 0.0)
+ {
+ SPDLOG_DEBUG("GJK: edge AC");
+ T f1 = 1.0 / (d2 + d5);
+ T lm = d2 * f1;
+ T mu = d5 * f1;
+ return {mu, 0.0, lm};
}
- return {std::move(smin), vmin};
+ T va = d3 * d6 - d6 * d4 + d4 * d5;
+ if (va < 0.0 and d4 > 0.0 and d6 > 0.0)
+ {
+ SPDLOG_DEBUG("GJK: edge BC");
+ T f1 = 1.0 / (d4 + d6);
+ T lm = d4 * f1;
+ T mu = d6 * f1;
+ return {0.0, mu, lm};
+ }
+
+ SPDLOG_DEBUG("GJK: triangle ABC");
+ T f1 = 1.0 / (va + vb + vc);
+ return {va * f1, vb * f1, vc * f1};
}
case 4:
{
- auto s0 = s.template subspan<0, 3>();
- auto s1 = s.template subspan<3, 3>();
- auto s2 = s.template subspan<6, 3>();
- auto s3 = s.template subspan<9, 3>();
- auto W1 = math::cross(s0, s1);
- auto W2 = math::cross(s2, s3);
-
- std::array<T, 4> B;
- B[0] = std::transform_reduce(s2.begin(), s2.end(), W1.begin(), 0.0);
- B[1] = -std::transform_reduce(s3.begin(), s3.end(), W1.begin(), 0.0);
- B[2] = std::transform_reduce(s0.begin(), s0.end(), W2.begin(), 0.0);
- B[3] = -std::transform_reduce(s1.begin(), s1.end(), W2.begin(), 0.0);
+ // Most complex case, where simplex is a tetrahedron, with 15 possible
+ // outcomes (4 vertices, 6 edges, 4 facets and the interior).
+ std::vector<T> rv = {0.0, 0.0, 0.0, 0.0};
- const bool signDetM = std::signbit(std::reduce(B.begin(), B.end(), 0.0));
- std::array<bool, 4> f_inside;
+ T d[4][4];
for (int i = 0; i < 4; ++i)
- f_inside[i] = (std::signbit(B[i]) == signDetM);
-
- if (f_inside[1] and f_inside[2] and f_inside[3])
+ // Compute dot products at each vertex
{
- if (f_inside[0]) // The origin is inside the tetrahedron
- return {std::vector<T>(s.begin(), s.end()), {0, 0, 0}};
- else // The origin projection P faces BCD
- return nearest_simplex<T>(s.template subspan<0, 3 * 3>());
+ std::span<const T, 3> si(s.begin() + i * 3, 3);
+ T sii = dot3(si, si);
+ bool out = true;
+ for (int j = 0; j < 4; ++j)
+ {
+ std::span<const T, 3> sj(s.begin() + j * 3, 3);
+ if (i != j)
+ d[i][j] = (sii - dot3(si, sj));
+ SPDLOG_DEBUG("d[{}][{}] = {}", i, j, static_cast<double>(d[i][j]));
+ if (d[i][j] > 0.0)
+ out = false;
+ }
+ if (out)
+ {
+ // Return if a vertex is closest
+ rv[i] = 1.0;
+ return rv;
+ }
}
- // Test ACD, ABD and/or ABC
- std::vector<T> smin;
- std::array<T, 3> vmin = {0, 0, 0};
- constexpr int facets[3][3] = {{0, 1, 3}, {0, 2, 3}, {1, 2, 3}};
- T qmin = std::numeric_limits<T>::max();
- std::vector<T> M(9);
- for (int i = 0; i < 3; ++i)
+ SPDLOG_DEBUG("Check for edges");
+
+ // Check if an edge is closest
+ T v[6][2] = {{0.0}};
+ int edges[6][2] = {{2, 3}, {1, 3}, {1, 2}, {0, 3}, {0, 2}, {0, 1}};
+ for (int i = 0; i < 6; ++i)
{
- if (f_inside[i + 1] == false)
+ // Four vertices of the tetrahedron, j0 and j1 at the ends of the current
+ // edge and j2 and j3 on the opposing edge.
+ int j0 = edges[i][0];
+ int j1 = edges[i][1];
+ int j2 = edges[5 - i][0];
+ int j3 = edges[5 - i][1];
+ v[i][0] = d[j1][j2] * d[j0][j1] - d[j0][j1] * d[j1][j0]
+ + d[j1][j0] * d[j0][j2];
+ v[i][1] = d[j1][j3] * d[j0][j1] - d[j0][j1] * d[j1][j0]
+ + d[j1][j0] * d[j0][j3];
+
+ SPDLOG_DEBUG("v[{}] = {},{}", i, (double)v[i][0], (double)v[i][1]);
+ if (v[i][0] <= 0.0 and v[i][1] <= 0.0 and d[j0][j1] >= 0.0
+ and d[j1][j0] >= 0.0)
{
- std::copy_n(std::next(s.begin(), 3 * facets[i][0]), 3, M.begin());
- std::copy_n(std::next(s.begin(), 3 * facets[i][1]), 3,
- std::next(M.begin(), 3));
- std::copy_n(std::next(s.begin(), 3 * facets[i][2]), 3,
- std::next(M.begin(), 6));
-
- const auto [snew, v] = nearest_simplex<T>(M);
- T q = std::transform_reduce(v.begin(), v.end(), v.begin(), 0);
- if (q < qmin)
- {
- qmin = q;
- vmin = v;
- smin = snew;
- }
+ // On an edge
+ T f1 = 1.0 / (d[j0][j1] + d[j1][j0]);
+ rv[j0] = f1 * d[j1][j0];
+ rv[j1] = f1 * d[j0][j1];
+ return rv;
}
}
- return {smin, vmin};
+
+ // Now check the facets of a tetrahedron
+ std::array<T, 4> w;
+ std::array<T, 9> M;
+ std::span<const T, 9> Mspan(M.begin(), M.size());
+ std::copy(s.begin(), s.begin() + 9, M.begin());
+ w[0] = -det3(Mspan);
+ std::copy(s.begin() + 9, s.begin() + 12, M.begin() + 6);
+ w[1] = det3(Mspan);
+ std::copy(s.begin() + 6, s.begin() + 9, M.begin() + 3);
+ w[2] = -det3(Mspan);
+ std::copy(s.begin() + 3, s.begin() + 6, M.begin() + 0);
+ w[3] = det3(Mspan);
+ T wsum = w[0] + w[1] + w[2] + w[3];
+ if (wsum < 0.0)
+ {
+ w[0] = -w[0];
+ w[1] = -w[1];
+ w[2] = -w[2];
+ w[3] = -w[3];
+ wsum = -wsum;
+ }
+
+ if (w[0] < 0.0 and v[2][0] > 0.0 and v[4][0] > 0.0 and v[5][0] > 0.0)
+ {
+ T f1 = 1.0 / (v[2][0] + v[4][0] + v[5][0]);
+ return {v[2][0] * f1, v[4][0] * f1, v[5][0] * f1, 0.0};
+ }
+
+ if (w[1] < 0.0 and v[1][0] > 0.0 and v[3][0] > 0.0 and v[5][1] > 0.0)
+ {
+ T f1 = 1.0 / (v[1][0] + v[3][0] + v[5][1]);
+ return {v[1][0] * f1, v[3][0] * f1, 0.0, v[5][1] * f1};
+ }
+
+ if (w[2] < 0.0 and v[0][0] > 0.0 and v[3][1] > 0 and v[4][1] > 0.0)
+ {
+ T f1 = 1.0 / (v[0][0] + v[3][1] + v[4][1]);
+ return {v[0][0] * f1, 0.0, v[3][1] * f1, v[4][1] * f1};
+ }
+
+ if (w[3] < 0.0 and v[0][1] > 0.0 and v[1][1] > 0.0 and v[2][1] > 0.0)
+ {
+ T f1 = 1.0 / (v[0][1] + v[1][1] + v[2][1]);
+ return {0.0, v[0][1] * f1, v[1][1] * f1, v[2][1] * f1};
+ }
+
+ // Point lies in interior of tetrahedron with these barycentric coordinates
+ return {w[3] / wsum, w[2] / wsum, w[1] / wsum, w[0] / wsum};
}
default:
throw std::runtime_error("Number of rows defining simplex not supported.");
@@ -223,7 +268,10 @@
}
/// @brief 'support' function, finds point p in bd which maximises p.v
-template <std::floating_point T>
+/// @param bd Body described by set of 3D points, flattened
+/// @param v A point in 3D
+/// @returns Point p in `bd` which maximises p.v
+template <typename T>
std::array<T, 3> support(std::span<const T> bd, std::array<T, 3> v)
{
int i = 0;
@@ -242,40 +290,50 @@
}
} // namespace impl_gjk
-/// @brief Compute the distance between two convex bodies p and q, each
+/// @brief Compute the distance between two convex bodies `p0` and `q0`, each
/// defined by a set of points.
///
/// Uses the Gilbert–Johnson–Keerthi (GJK) distance algorithm.
///
-/// @param[in] p Body 1 list of points, shape (num_points, 3). Row-major
+/// @param[in] p0 Body 1 list of points, `shape=(num_points, 3)`. Row-major
/// storage.
-/// @param[in] q Body 2 list of points, shape (num_points, 3). Row-major
+/// @param[in] q0 Body 2 list of points, `shape=(num_points, 3)`. Row-major
/// storage.
+/// @tparam T Floating point type
+/// @tparam U Floating point type used for geometry computations internally,
+/// which should be higher precision than T, to maintain accuracy.
/// @return shortest vector between bodies
-template <std::floating_point T>
-std::array<T, 3> compute_distance_gjk(std::span<const T> p,
- std::span<const T> q)
+template <std::floating_point T,
+ typename U = boost::multiprecision::cpp_bin_float_double_extended>
+std::array<T, 3> compute_distance_gjk(std::span<const T> p0,
+ std::span<const T> q0)
{
- assert(p.size() % 3 == 0);
- assert(q.size() % 3 == 0);
+ assert(p0.size() % 3 == 0);
+ assert(q0.size() % 3 == 0);
+
+ // Copy from T to type U
+ std::vector<U> p(p0.begin(), p0.end());
+ std::vector<U> q(q0.begin(), q0.end());
constexpr int maxk = 15; // Maximum number of iterations of the GJK algorithm
// Tolerance
- constexpr T eps = 1.0e4 * std::numeric_limits<T>::epsilon();
+ const U eps = 1.0e4 * std::numeric_limits<T>::epsilon();
// Initialise vector and simplex
- std::array<T, 3> v = {p[0] - q[0], p[1] - q[1], p[2] - q[2]};
- std::vector<T> s = {v[0], v[1], v[2]};
+ std::array<U, 3> v = {p[0] - q[0], p[1] - q[1], p[2] - q[2]};
+ std::vector<U> s = {v[0], v[1], v[2]};
// Begin GJK iteration
int k;
for (k = 0; k < maxk; ++k)
{
// Support function
- std::array w1 = impl_gjk::support(p, {-v[0], -v[1], -v[2]});
- std::array w0 = impl_gjk::support(q, {v[0], v[1], v[2]});
- const std::array w = {w1[0] - w0[0], w1[1] - w0[1], w1[2] - w0[2]};
+ std::array w1
+ = impl_gjk::support(std::span<const U>(p), {-v[0], -v[1], -v[2]});
+ std::array w0
+ = impl_gjk::support(std::span<const U>(q), {v[0], v[1], v[2]});
+ const std::array<U, 3> w = {w1[0] - w0[0], w1[1] - w0[1], w1[2] - w0[2]};
// Break if any existing points are the same as w
assert(s.size() % 3 == 0);
@@ -291,28 +349,49 @@
break;
// 1st exit condition (v - w).v = 0
- const T vnorm2 = v[0] * v[0] + v[1] * v[1] + v[2] * v[2];
- const T vw = vnorm2 - (v[0] * w[0] + v[1] * w[1] + v[2] * w[2]);
+ const U vnorm2 = impl_gjk::dot3(v, v);
+ const U vw = vnorm2 - impl_gjk::dot3(v, w);
if (vw < (eps * vnorm2) or vw < eps)
break;
+ SPDLOG_DEBUG("GJK: vw={}/{}", static_cast<double>(vw),
+ static_cast<double>(eps));
+
// Add new vertex to simplex
s.insert(s.end(), w.begin(), w.end());
// Find nearest subset of simplex
- auto [snew, vnew] = impl_gjk::nearest_simplex<T>(s);
- s.assign(snew.data(), snew.data() + snew.size());
- v = {vnew[0], vnew[1], vnew[2]};
+ std::vector<U> lmn = impl_gjk::nearest_simplex<U>(s);
+
+ // Recompute v and keep points with non-zero values in lmn
+ std::size_t j = 0;
+ v = {0.0, 0.0, 0.0};
+ for (std::size_t i = 0; i < lmn.size(); ++i)
+ {
+ std::span<const U> sc(std::next(s.begin(), 3 * i), 3);
+ if (lmn[i] > 0.0)
+ {
+ v[0] += lmn[i] * sc[0];
+ v[1] += lmn[i] * sc[1];
+ v[2] += lmn[i] * sc[2];
+ if (i > j)
+ std::copy(sc.begin(), sc.end(), std::next(s.begin(), 3 * j));
+ ++j;
+ }
+ }
+ SPDLOG_DEBUG("new s size={}", 3 * j);
+ s.resize(3 * j);
+ const U vn = impl_gjk::dot3(v, v);
// 2nd exit condition - intersecting or touching
- if ((v[0] * v[0] + v[1] * v[1] + v[2] * v[2]) < eps * eps)
+ if (vn < eps * eps)
break;
}
if (k == maxk)
throw std::runtime_error("GJK error - max iteration limit reached");
- return v;
+ return {static_cast<T>(v[0]), static_cast<T>(v[1]), static_cast<T>(v[2])};
}
} // namespace dolfinx::geometry
Index: fenics-dolfinx/python/dolfinx/geometry.py
===================================================================
--- fenics-dolfinx.orig/python/dolfinx/geometry.py 2025-10-13 14:45:26.932905482 +0200
+++ fenics-dolfinx/python/dolfinx/geometry.py 2025-10-13 14:45:26.929370742 +0200
@@ -269,4 +269,9 @@
Shortest vector between the two bodies.
"""
- return _cpp.geometry.compute_distance_gjk(p, q)
+ assert p.dtype == q.dtype
+ if np.issubdtype(p.dtype, np.float32):
+ return _cpp.geometry.compute_distance_gjk_float32(p, q)
+ elif np.issubdtype(p.dtype, np.float64):
+ return _cpp.geometry.compute_distance_gjk_float64(p, q)
+ raise RuntimeError("Invalid dtype in compute_distance_gjk")
Index: fenics-dolfinx/python/dolfinx/wrappers/geometry.cpp
===================================================================
--- fenics-dolfinx.orig/python/dolfinx/wrappers/geometry.cpp 2025-10-13 14:45:26.932905482 +0200
+++ fenics-dolfinx/python/dolfinx/wrappers/geometry.cpp 2025-10-13 14:46:30.620310754 +0200
@@ -151,18 +151,24 @@
},
nb::arg("mesh"), nb::arg("candidate_cells"), nb::arg("points"));
+ std::string gjk_name = "compute_distance_gjk_" + type;
m.def(
- "compute_distance_gjk",
+ gjk_name.c_str(),
[](nb::ndarray<const T, nb::c_contig> p,
nb::ndarray<const T, nb::c_contig> q)
{
std::size_t p_s0 = p.ndim() == 1 ? 1 : p.shape(0);
std::size_t q_s0 = q.ndim() == 1 ? 1 : q.shape(0);
std::span<const T> _p(p.data(), 3 * p_s0), _q(q.data(), 3 * q_s0);
- std::array<T, 3> d = dolfinx::geometry::compute_distance_gjk<T>(_p, _q);
+ // Use double when T==float, and double_extended when T==double
+ using U = std::conditional<
+ std::is_same_v<T, float>, double,
+ boost::multiprecision::cpp_bin_float_double_extended>::type;
+
+ std::array<T, 3> d
+ = dolfinx::geometry::compute_distance_gjk<T, U>(_p, _q);
return dolfinx_wrappers::as_nbarray_copy(d, {d.size()});
},
- // nb::rv_policy::copy,
nb::arg("p"), nb::arg("q"));
m.def(
Index: fenics-dolfinx/python/test/unit/geometry/test_gjk.py
===================================================================
--- fenics-dolfinx.orig/python/test/unit/geometry/test_gjk.py 2025-10-13 14:45:26.932905482 +0200
+++ fenics-dolfinx/python/test/unit/geometry/test_gjk.py 2025-10-13 14:45:26.929780659 +0200
@@ -174,7 +174,11 @@
cube1 = cubes[c1] + np.array([dx + delta, 0, 0])
c0rot = r.apply(cube0)
c1rot = r.apply(cube1)
- distance = np.linalg.norm(compute_distance_gjk(c0rot, c1rot))
+ assert c0rot.dtype == dtype
+ assert c1rot.dtype == dtype
+ d = compute_distance_gjk(c0rot, c1rot)
+ assert d.dtype == dtype
+ distance = np.linalg.norm(d)
assert np.isclose(distance, delta)
|