From 675677ec67c6b922b3a5e602c8bf3dbb562bd687 Mon Sep 17 00:00:00 2001 From: Hans Goudey Date: Wed, 9 Jun 2021 14:53:39 -0500 Subject: Splines: Add API functions for interpolating data First, expand on the interpolation to evaluated points with a templated helper function, and a function that takes a GSPan. Next, add a set of functions to `Spline` for interpolating at arbitrary intervals between the evaluated points. The code for doing that isn't that complicated anyway, but it's nice to avoid repeating, and it might make it easier to unroll the special cases for the first and last points if we require the index factors to be sorted. --- source/blender/blenkernel/BKE_spline.hh | 26 +++++++++++++++ source/blender/blenkernel/intern/spline_base.cc | 41 ++++++++++++++++++++++-- source/blender/blenkernel/intern/spline_nurbs.cc | 8 ++--- 3 files changed, 69 insertions(+), 6 deletions(-) (limited to 'source/blender/blenkernel') diff --git a/source/blender/blenkernel/BKE_spline.hh b/source/blender/blenkernel/BKE_spline.hh index fc1292e3620..dfbe82f31fd 100644 --- a/source/blender/blenkernel/BKE_spline.hh +++ b/source/blender/blenkernel/BKE_spline.hh @@ -172,6 +172,25 @@ class Spline { blender::Array sample_uniform_index_factors(const int samples_size) const; LookupResult lookup_data_from_index_factor(const float index_factor) const; + void sample_based_on_index_factors(const blender::fn::GVArray &src, + blender::Span index_factors, + blender::fn::GMutableSpan dst) const; + template + void sample_based_on_index_factors(const blender::VArray &src, + blender::Span index_factors, + blender::MutableSpan dst) const + { + this->sample_based_on_index_factors( + blender::fn::GVArray_For_VArray(src), index_factors, blender::fn::GMutableSpan(dst)); + } + template + void sample_based_on_index_factors(blender::Span src, + blender::Span index_factors, + blender::MutableSpan dst) const + { + this->sample_based_on_index_factors(blender::VArray_For_Span(src), index_factors, dst); + } + /** * Interpolate a virtual array of data with the size of the number of control points to the * evaluated points. For poly splines, the lifetime of the returned virtual array must not @@ -179,6 +198,13 @@ class Spline { */ virtual blender::fn::GVArrayPtr interpolate_to_evaluated_points( const blender::fn::GVArray &source_data) const = 0; + blender::fn::GVArrayPtr interpolate_to_evaluated_points(blender::fn::GSpan data) const; + template + blender::fn::GVArray_Typed interpolate_to_evaluated_points(blender::Span data) const + { + return blender::fn::GVArray_Typed( + this->interpolate_to_evaluated_points(blender::fn::GSpan(data))); + } protected: virtual void correct_end_tangents() const = 0; diff --git a/source/blender/blenkernel/intern/spline_base.cc b/source/blender/blenkernel/intern/spline_base.cc index 11620a30948..9f8c215b31f 100644 --- a/source/blender/blenkernel/intern/spline_base.cc +++ b/source/blender/blenkernel/intern/spline_base.cc @@ -16,6 +16,7 @@ #include "BLI_array.hh" #include "BLI_span.hh" +#include "BLI_task.hh" #include "BLI_timeit.hh" #include "BKE_spline.hh" @@ -27,6 +28,12 @@ using blender::float3; using blender::IndexRange; using blender::MutableSpan; using blender::Span; +using blender::fn::GMutableSpan; +using blender::fn::GSpan; +using blender::fn::GVArray; +using blender::fn::GVArray_For_GSpan; +using blender::fn::GVArray_Typed; +using blender::fn::GVArrayPtr; Spline::Type Spline::type() const { @@ -234,8 +241,7 @@ Span Spline::evaluated_normals() const calculate_normals_z_up(tangents, normals); /* Rotate the generated normals with the interpolated tilt data. */ - blender::fn::GVArray_Typed tilts{ - this->interpolate_to_evaluated_points(blender::fn::GVArray_For_Span(this->tilts()))}; + GVArray_Typed tilts = this->interpolate_to_evaluated_points(this->tilts()); for (const int i : normals.index_range()) { normals[i] = rotate_direction_around_axis(normals[i], tangents[i], tilts[i]); } @@ -341,3 +347,34 @@ void Spline::bounds_min_max(float3 &min, float3 &max, const bool use_evaluated) minmax_v3v3_v3(min, max, position); } } + +GVArrayPtr Spline::interpolate_to_evaluated_points(GSpan data) const +{ + return this->interpolate_to_evaluated_points(GVArray_For_GSpan(data)); +} + +/** + * Sample any input data with a value for each evaluated point (already interpolated to evaluated + * points) to arbitrary parameters in betwen the evaluated points. The interpolation is quite + * simple, but this handles the cyclic and end point special cases. + */ +void Spline::sample_based_on_index_factors(const GVArray &src, + Span index_factors, + GMutableSpan dst) const +{ + BLI_assert(src.size() == this->evaluated_points_size()); + + blender::attribute_math::convert_to_static_type(src.type(), [&](auto dummy) { + using T = decltype(dummy); + const GVArray_Typed src_typed = src.typed(); + MutableSpan dst_typed = dst.typed(); + blender::parallel_for(dst_typed.index_range(), 1024, [&](IndexRange range) { + for (const int i : range) { + const LookupResult interp = this->lookup_data_from_index_factor(index_factors[i]); + dst_typed[i] = blender::attribute_math::mix2(interp.factor, + src_typed[interp.evaluated_index], + src_typed[interp.next_evaluated_index]); + } + }); + }); +} diff --git a/source/blender/blenkernel/intern/spline_nurbs.cc b/source/blender/blenkernel/intern/spline_nurbs.cc index cae206341a0..bfb0d652b1a 100644 --- a/source/blender/blenkernel/intern/spline_nurbs.cc +++ b/source/blender/blenkernel/intern/spline_nurbs.cc @@ -26,6 +26,7 @@ using blender::float3; using blender::IndexRange; using blender::MutableSpan; using blender::Span; +using blender::fn::GVArray_Typed; SplinePtr NURBSpline::copy() const { @@ -434,10 +435,9 @@ Span NURBSpline::evaluated_positions() const const int eval_size = this->evaluated_points_size(); evaluated_position_cache_.resize(eval_size); - blender::fn::GVArray_Typed evaluated_positions{ - this->interpolate_to_evaluated_points(blender::fn::GVArray_For_Span(positions_))}; - - evaluated_positions->materialize(evaluated_position_cache_); + /* TODO: Avoid copying the evaluated data from the temporary array. */ + GVArray_Typed evaluated = Spline::interpolate_to_evaluated_points(positions_.as_span()); + evaluated->materialize(evaluated_position_cache_); position_cache_dirty_ = false; return evaluated_position_cache_; -- cgit v1.2.3