tornavis/source/blender/blenlib/intern/length_parameterize.cc

61 lines
2.1 KiB
C++

/* SPDX-FileCopyrightText: 2023 Blender Authors
*
* SPDX-License-Identifier: GPL-2.0-or-later */
#include "BLI_length_parameterize.hh"
#include "BLI_task.hh"
namespace blender::length_parameterize {
void sample_uniform(const Span<float> lengths,
const bool include_last_point,
MutableSpan<int> r_segment_indices,
MutableSpan<float> r_factors)
{
const int count = r_segment_indices.size();
BLI_assert(count > 0);
BLI_assert(lengths.size() >= 1);
BLI_assert(std::is_sorted(lengths.begin(), lengths.end()));
if (count == 1) {
r_segment_indices[0] = 0;
r_factors[0] = 0.0f;
return;
}
const float total_length = lengths.last();
const float step_length = total_length / (count - include_last_point);
threading::parallel_for(IndexRange(count), 512, [&](const IndexRange range) {
SampleSegmentHint hint;
for (const int i : range) {
/* Use minimum to avoid issues with floating point accuracy. */
const float sample_length = std::min(total_length, i * step_length);
sample_at_length(lengths, sample_length, r_segment_indices[i], r_factors[i], &hint);
}
});
}
void sample_at_lengths(const Span<float> accumulated_segment_lengths,
const Span<float> sample_lengths,
MutableSpan<int> r_segment_indices,
MutableSpan<float> r_factors)
{
BLI_assert(
std::is_sorted(accumulated_segment_lengths.begin(), accumulated_segment_lengths.end()));
BLI_assert(std::is_sorted(sample_lengths.begin(), sample_lengths.end()));
const int count = sample_lengths.size();
BLI_assert(count == r_segment_indices.size());
BLI_assert(count == r_factors.size());
threading::parallel_for(IndexRange(count), 512, [&](const IndexRange range) {
SampleSegmentHint hint;
for (const int i : range) {
const float sample_length = sample_lengths[i];
sample_at_length(
accumulated_segment_lengths, sample_length, r_segment_indices[i], r_factors[i], &hint);
}
});
}
} // namespace blender::length_parameterize