81 lines
2.4 KiB
C++
81 lines
2.4 KiB
C++
|
/* SPDX-License-Identifier: GPL-2.0-or-later */
|
||
|
|
|
||
|
|
#pragma once
|
||
|
|
|
||
|
|
/** \file
|
||
|
|
* \ingroup bli
|
||
|
|
*/
|
||
|
|
|
||
|
|
#include "BLI_math_base.hh"
|
||
|
|
#include "BLI_math_color.hh"
|
||
|
|
#include "BLI_math_vector.hh"
|
||
|
|
#include "BLI_vector.hh"
|
||
|
|
|
||
|
|
namespace blender::length_parameterize {
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Return the size of the necessary lengths array for a group of points, taking into account the
|
||
|
|
* possible last cyclic segment.
|
||
|
|
*
|
||
|
|
* \note This is the same as #bke::curves::curve_segment_size.
|
||
|
|
*/
|
||
|
|
inline int lengths_num(const int points_num, const bool cyclic)
|
||
|
|
{
|
||
|
|
return cyclic ? points_num : points_num - 1;
|
||
|
|
}
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Accumulate the length of the next segment into each point.
|
||
|
|
*/
|
||
|
|
template<typename T>
|
||
|
|
void accumulate_lengths(const Span<T> values, const bool cyclic, MutableSpan<float> lengths)
|
||
|
|
{
|
||
|
|
BLI_assert(lengths.size() == lengths_num(values.size(), cyclic));
|
||
|
|
float length = 0.0f;
|
||
|
|
for (const int i : IndexRange(values.size() - 1)) {
|
||
|
|
length += math::distance(values[i], values[i + 1]);
|
||
|
|
lengths[i] = length;
|
||
|
|
}
|
||
|
|
if (cyclic) {
|
||
|
|
lengths.last() = length + math::distance(values.last(), values.first());
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
template<typename T>
|
||
|
|
void linear_interpolation(const Span<T> src,
|
||
|
|
const Span<int> indices,
|
||
|
|
const Span<float> factors,
|
||
|
|
MutableSpan<T> dst)
|
||
|
|
{
|
||
|
|
BLI_assert(indices.size() == factors.size());
|
||
|
|
BLI_assert(indices.size() == dst.size());
|
||
|
|
const int last_src_index = src.index_range().last();
|
||
|
|
|
||
|
|
int cyclic_sample_count = 0;
|
||
|
|
for (int i = indices.index_range().last(); i > 0; i--) {
|
||
|
|
if (indices[i] != last_src_index) {
|
||
|
|
break;
|
||
|
|
}
|
||
|
|
dst[i] = math::interpolate(src.last(), src.first(), factors[i]);
|
||
|
|
cyclic_sample_count++;
|
||
|
|
}
|
||
|
|
|
||
|
|
for (const int i : dst.index_range().drop_back(cyclic_sample_count)) {
|
||
|
|
dst[i] = math::interpolate(src[indices[i]], src[indices[i] + 1], factors[i]);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Find the given number of points, evenly spaced along the provided length. For non-cyclic
|
||
|
|
* sequences, the first point will always be included, and last point will always be included if
|
||
|
|
* the #count is greater than zero. For cyclic sequences, the first point will always be included.
|
||
|
|
*
|
||
|
|
* \warning The #count argument must be greater than zero.
|
||
|
|
*/
|
||
|
|
void create_uniform_samples(Span<float> lengths,
|
||
|
|
bool cyclic,
|
||
|
|
MutableSpan<int> indices,
|
||
|
|
MutableSpan<float> factors);
|
||
|
|
|
||
|
|
} // namespace blender::length_parameterize
|