ENH: More type deduction

Project, Reflect, Stereo, Ortho
This commit is contained in:
David Allemang
2023-02-02 23:05:08 -05:00
parent 4eee992315
commit 2e892a764e
2 changed files with 49 additions and 47 deletions

View File

@@ -28,44 +28,41 @@ Eigen::Matrix<float, N, N> mirror(const tc::Group<> &group) {
return res;
}
template<unsigned N>
vec<N> stereo(const vec<N + 1> &v) {
vec<N> r;
for (int i = 0; i < N; ++i) {
r[i] = v[i] / (1 - v[N]);
}
return r;
struct Stereo {
template<class U>
auto operator()(U &&mat) const {
const auto Rows = std::remove_reference<U>::type::RowsAtCompileTime;
return std::forward<U>(mat).template topRows<Rows - 1>().rowwise() / (1 - mat.template bottomRows<1>());
}
};
template<unsigned N>
vec<N> ortho(const vec<N + 1> &v) {
vec<N> r;
for (int i = 0; i < N; ++i) {
r[i] = v[i];
}
return r;
struct Ortho {
template<class U>
auto operator()(U &&mat) const {
const auto Rows = std::remove_reference<U>::type::RowsAtCompileTime;
return std::forward<U>(mat).template topRows<Rows - 1>();
}
};
template<class V>
V project(const V &vec, const V &target) {
return vec.dot(target) / target.dot(target) * target;
struct Project {
template<class U, class V>
auto operator()(U &&point, V &&axis) const {
return point.dot(axis) / axis.dot(axis) * std::forward<V>(axis);
}
};
template<class V>
V reflect(const V &a, const V &axis) {
return a - 2.f * project(a, axis);
}
template<class Point, class Axis>
auto project_(const Point &point, const Axis &axis) {
return axis.dot(point) / axis.dot(axis) * axis;
struct Reflect {
template<class U, class V>
auto operator()(U &&point, V &&axis) const {
return std::forward<U>(point) - 2 * Project()(point, axis);
}
};
template<class Mat>
Mat gram_schmidt(Mat mat) {
for (int i = 0; i < mat.cols(); ++i) {
for (int j = i + 1; j < mat.cols(); ++j) {
mat.col(j) -= project_(mat.col(j), mat.col(i));
mat.col(j) -= Project()(mat.col(j), mat.col(i));
}
}
return mat;

View File

@@ -90,13 +90,18 @@ std::vector<vec4> points(const tc::Group<> &group, const C &coords) {
tc::Path<vec5> path(cosets, mirrors.colwise());
std::vector<vec5> higher(path.order());
path.walk(start, reflect<vec5>, higher.begin());
Eigen::Array<float, 5, Eigen::Dynamic> higher(5, path.order());
path.walk(start, Reflect(), higher.matrix().colwise().begin());
// std::vector<vec5> higher(path.order());
// path.walk(start, Reflect(), higher.begin());
std::vector<vec4> lower(higher.size());
std::transform(higher.begin(), higher.end(), lower.begin(), stereo<4>);
// Eigen::Array4Xf lower = higher.topRows<4>().rowwise() / (1 - higher.bottomRows<1>());
Eigen::Array4Xf lower = Stereo()(higher);
return lower;
std::vector<vec4> vec(lower.cols());
std::copy(lower.colwise().begin(), lower.colwise().end(), vec.begin());
return vec;
}
template<unsigned N>