+++ /dev/null
-/* -*- C++ -*- ------------------------------------------------------------
-
-Copyright (c) 2007 Jesse Anders and Demian Nave http://cmldev.net/
-
-The Configurable Math Library (CML) is distributed under the terms of the
-Boost Software License, v1.0 (see cml/LICENSE for details).
-
- *-----------------------------------------------------------------------*/
-/** @file
- * @brief
- */
-
-#ifndef vector_misc_h
-#define vector_misc_h
-
-#include <cml/mathlib/coord_conversion.h>
-
-/* Miscellaneous vector functions. */
-
-namespace cml {
-
-/* Function to project a vector v onto a hyperplane specified by a unit-length
- * normal n.
- *
- * @todo: Clean up promotion code.
- */
-
-template < class VecT_1, class VecT_2 >
-typename detail::CrossPromote<VecT_1,VecT_2>::promoted_vector
-project_to_hplane(const VecT_1& v, const VecT_2& n)
-{
- typedef typename detail::CrossPromote<VecT_1,VecT_2>::promoted_vector
- result_type;
-
- result_type result;
- et::detail::Resize(result, v.size());
-
- result = v - dot(v,n) * n;
- return result;
-}
-
-/* Return a vector perpendicular (CCW) to a 2D vector. */
-template < class VecT > vector< typename VecT::value_type, fixed<2> >
-perp(const VecT& v)
-{
- typedef vector< typename VecT::value_type, fixed<2> > temporary_type;
-
- /* Checking */
- detail::CheckVec2(v);
-
- return temporary_type(-v[1],v[0]);
-}
-
-/* @todo: unit_cross() and cross_cardinal() should probably go in
- * vector_products.h, but I'm trying to avoid modifying the existing codebase
- * for now.
- */
-
-/** Return normalized cross product of two vectors */
-template< class LeftT, class RightT >
-typename detail::CrossPromote<LeftT,RightT>::promoted_vector
-unit_cross(const LeftT& left, const RightT& right) {
- /* @todo: This will probably break with dynamic<> vectors */
- return normalize(cross(left,right));
-}
-
-/** Return the cross product of v and the i'th cardinal basis vector */
-template < class VecT > vector< typename VecT::value_type, fixed<3> >
-cross_cardinal(const VecT& v, size_t i)
-{
- typedef vector< typename VecT::value_type, fixed<3> > vector_type;
- typedef typename vector_type::value_type value_type;
-
- /* Checking */
- detail::CheckVec3(v);
- detail::CheckIndex3(i);
-
- size_t j, k;
- cyclic_permutation(i, i, j, k);
- vector_type result;
- result[i] = value_type(0);
- result[j] = v[k];
- result[k] = -v[j];
- return result;
-}
-
-/** Return the cross product of the i'th cardinal basis vector and v */
-template < class VecT > vector< typename VecT::value_type, fixed<3> >
-cross_cardinal(size_t i, const VecT& v)
-{
- typedef vector< typename VecT::value_type, fixed<3> > vector_type;
- typedef typename vector_type::value_type value_type;
-
- /* Checking */
- detail::CheckVec3(v);
- detail::CheckIndex3(i);
-
- size_t j, k;
- cyclic_permutation(i, i, j, k);
- vector_type result;
- result[i] = value_type(0);
- result[j] = -v[k];
- result[k] = v[j];
- return result;
-}
-
-/** Rotate a 3D vector v about a unit-length vector n. */
-template< class VecT_1, class VecT_2, typename Real >
-vector<
- typename et::ScalarPromote<
- typename VecT_1::value_type,
- typename VecT_2::value_type
- >::type,
- fixed<3>
->
-rotate_vector(const VecT_1& v, const VecT_2& n, Real angle)
-{
- typedef vector<
- typename et::ScalarPromote<
- typename VecT_1::value_type,
- typename VecT_2::value_type
- >::type,
- fixed<3>
- > result_type;
-
- /* Checking */
- detail::CheckVec3(v);
- detail::CheckVec3(n);
-
- result_type parallel = dot(v,n)*n;
- return (
- std::cos(angle)*(v-parallel) + std::sin(angle)*cross(n,v) + parallel
- );
-}
-
-/** Rotate a 2D vector v about a unit-length vector n. */
-template< class VecT, typename Real >
-vector< typename VecT::value_type, fixed<2> >
-rotate_vector_2D(const VecT& v, Real angle)
-{
- typedef vector< typename VecT::value_type, fixed<2> > result_type;
- typedef typename result_type::value_type value_type;
-
- /* Checking */
- detail::CheckVec2(v);
-
- value_type s = std::sin(angle);
- value_type c = std::cos(angle);
-
- return result_type(c * v[0] - s * v[1], s * v[0] + c * v[1]);
-}
-
-/** Random unit 3D or 2D vector
- *
- * @todo: This is just placeholder code for what will be a more thorough
- * 'random unit' implementation:
- *
- * - All dimensions will be handled uniformly if practical, perhaps through
- * a normal distrubution PRNG.
- *
- * - Failing that (or perhaps even in this case), dimensions 2 and 3 will be
- * dispatched to special-case code, most likely implementing the algorithms
- * below.
- *
- * - Like the utility random functions, the option of using one's own PRGN
- * will be made available.
- *
- * @todo: Once N-d random vectors are supported, add a 'random unit
- * quaternion' function that wraps a call to random_unit() with a 4D vector as
- * the argument.
- */
-template < typename E, class A > void
-random_unit(vector<E,A>& v)
-{
- typedef vector<E,A> vector_type;
- typedef typename vector_type::value_type value_type;
-
- switch (v.size()) {
- case 3:
- {
- vector< E, fixed<3> > temp;
- spherical_to_cartesian(
- value_type(1),
- value_type(random_unit() * constants<value_type>::two_pi()),
- acos_safe(random_real(value_type(-1),value_type(1))),
- 2,
- colatitude,
- temp
- );
- v[0] = temp[0];
- v[1] = temp[1];
- v[2] = temp[2];
- break;
- }
- case 2:
- {
- vector< E, fixed<2> > temp;
- polar_to_cartesian(
- value_type(1),
- value_type(random_unit() * constants<value_type>::two_pi()),
- temp
- );
- v[0] = temp[0];
- v[1] = temp[1];
- break;
- }
- default:
- throw std::invalid_argument(
- "random_unit() for N-d vectors not implemented yet");
- break;
- }
-}
-
-/* Random vector within a given angle of a unit-length axis, i.e. in a cone
- * (3D) or wedge (2D).
- *
- * The same notes the appear above apply here too, more or less. One
- * difference is that this is really only useful in 2D and 3D (presumably), so
- * we'll probably just do a compile- or run-time dispatch as appropriate.
- *
- * Also, there may be a better algorithm for generating a random unit vector
- * in a cone; need to look into that.
- *
- * All of this 'temp' stuff is because there's no compile-time dispatch for
- * 3D and 2D vectors, but that'll be fixed soon.
- */
-
-template < typename E, class A, class VecT > void
-random_unit(vector<E,A>& v, const VecT& axis, E theta)
-{
- typedef vector<E,A> vector_type;
- typedef typename vector_type::value_type value_type;
-
- switch (v.size()) {
- case 3:
- {
- vector< E, fixed<3> > temp, n, temp_axis;
- temp_axis[0] = axis[0];
- temp_axis[1] = axis[1];
- temp_axis[2] = axis[2];
-
- /* @todo: Function for finding 'any perpendicular vector'? */
- n = axis_3D(cml::index_of_min_abs(axis[0],axis[1],axis[2]));
- n = cross(n,temp_axis);
-
- /* Rotate v 'away from' the axis by a random angle in the range
- * [-theta,theta]
- */
- temp = rotate_vector(temp_axis,n,random_real(-theta,theta));
-
- /* Rotate v about the axis by a random angle in the range [-pi,pi]
- */
- temp = rotate_vector(
- temp,
- temp_axis,
- random_real(
- -constants<value_type>::pi(),
- constants<value_type>::pi()
- )
- );
-
- v[0] = temp[0];
- v[1] = temp[1];
- v[2] = temp[2];
- break;
- }
- case 2:
- {
- vector< E, fixed<2> > temp, temp_axis;
- temp_axis[0] = axis[0];
- temp_axis[1] = axis[1];
- temp = rotate_vector_2D(temp_axis, random_real(-theta,theta));
- v[0] = temp[0];
- v[1] = temp[1];
- break;
- }
- default:
- throw std::invalid_argument(
- "random_unit(v,axis,theta) only implemented for 2D and 3D");
- break;
- }
-}
-
-/* NEW: Manhattan distance */
-
-template< class VecT_1, class VecT_2 >
-typename detail::DotPromote< VecT_1, VecT_2 >::promoted_scalar
-manhattan_distance(const VecT_1& v1, const VecT_2& v2) {
- /* Check that a promotion exists */
- typedef typename et::VectorPromote<
- VecT_1,VecT_2>::temporary_type promoted_vector;
-
- typedef typename detail::DotPromote< VecT_1, VecT_2 >::promoted_scalar scalar_type;
-
- scalar_type sum = scalar_type(0);
- for (size_t i = 0; i < v1.size(); ++i) {
- sum += std::fabs(v2[i]-v1[i]);
- }
- return sum;
-}
-
-} // namespace cml
-
-#endif
projects / chaz / yoink / blobdiff