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-rw-r--r--src/ipa/raspberrypi/controller/pwl.cpp269
1 files changed, 0 insertions, 269 deletions
diff --git a/src/ipa/raspberrypi/controller/pwl.cpp b/src/ipa/raspberrypi/controller/pwl.cpp
deleted file mode 100644
index 70c2e24b..00000000
--- a/src/ipa/raspberrypi/controller/pwl.cpp
+++ /dev/null
@@ -1,269 +0,0 @@
-/* SPDX-License-Identifier: BSD-2-Clause */
-/*
- * Copyright (C) 2019, Raspberry Pi Ltd
- *
- * pwl.cpp - piecewise linear functions
- */
-
-#include <cassert>
-#include <cmath>
-#include <stdexcept>
-
-#include "pwl.h"
-
-using namespace RPiController;
-
-int Pwl::read(const libcamera::YamlObject &params)
-{
- if (!params.size() || params.size() % 2)
- return -EINVAL;
-
- const auto &list = params.asList();
-
- for (auto it = list.begin(); it != list.end(); it++) {
- auto x = it->get<double>();
- if (!x)
- return -EINVAL;
- if (it != list.begin() && *x <= points_.back().x)
- return -EINVAL;
-
- auto y = (++it)->get<double>();
- if (!y)
- return -EINVAL;
-
- points_.push_back(Point(*x, *y));
- }
-
- return 0;
-}
-
-void Pwl::append(double x, double y, const double eps)
-{
- if (points_.empty() || points_.back().x + eps < x)
- points_.push_back(Point(x, y));
-}
-
-void Pwl::prepend(double x, double y, const double eps)
-{
- if (points_.empty() || points_.front().x - eps > x)
- points_.insert(points_.begin(), Point(x, y));
-}
-
-Pwl::Interval Pwl::domain() const
-{
- return Interval(points_[0].x, points_[points_.size() - 1].x);
-}
-
-Pwl::Interval Pwl::range() const
-{
- double lo = points_[0].y, hi = lo;
- for (auto &p : points_)
- lo = std::min(lo, p.y), hi = std::max(hi, p.y);
- return Interval(lo, hi);
-}
-
-bool Pwl::empty() const
-{
- return points_.empty();
-}
-
-double Pwl::eval(double x, int *spanPtr, bool updateSpan) const
-{
- int span = findSpan(x, spanPtr && *spanPtr != -1 ? *spanPtr : points_.size() / 2 - 1);
- if (spanPtr && updateSpan)
- *spanPtr = span;
- return points_[span].y +
- (x - points_[span].x) * (points_[span + 1].y - points_[span].y) /
- (points_[span + 1].x - points_[span].x);
-}
-
-int Pwl::findSpan(double x, int span) const
-{
- /*
- * Pwls are generally small, so linear search may well be faster than
- * binary, though could review this if large PWls start turning up.
- */
- int lastSpan = points_.size() - 2;
- /*
- * some algorithms may call us with span pointing directly at the last
- * control point
- */
- span = std::max(0, std::min(lastSpan, span));
- while (span < lastSpan && x >= points_[span + 1].x)
- span++;
- while (span && x < points_[span].x)
- span--;
- return span;
-}
-
-Pwl::PerpType Pwl::invert(Point const &xy, Point &perp, int &span,
- const double eps) const
-{
- assert(span >= -1);
- bool prevOffEnd = false;
- for (span = span + 1; span < (int)points_.size() - 1; span++) {
- Point spanVec = points_[span + 1] - points_[span];
- double t = ((xy - points_[span]) % spanVec) / spanVec.len2();
- if (t < -eps) /* off the start of this span */
- {
- if (span == 0) {
- perp = points_[span];
- return PerpType::Start;
- } else if (prevOffEnd) {
- perp = points_[span];
- return PerpType::Vertex;
- }
- } else if (t > 1 + eps) /* off the end of this span */
- {
- if (span == (int)points_.size() - 2) {
- perp = points_[span + 1];
- return PerpType::End;
- }
- prevOffEnd = true;
- } else /* a true perpendicular */
- {
- perp = points_[span] + spanVec * t;
- return PerpType::Perpendicular;
- }
- }
- return PerpType::None;
-}
-
-Pwl Pwl::inverse(bool *trueInverse, const double eps) const
-{
- bool appended = false, prepended = false, neither = false;
- Pwl inverse;
-
- for (Point const &p : points_) {
- if (inverse.empty())
- inverse.append(p.y, p.x, eps);
- else if (std::abs(inverse.points_.back().x - p.y) <= eps ||
- std::abs(inverse.points_.front().x - p.y) <= eps)
- /* do nothing */;
- else if (p.y > inverse.points_.back().x) {
- inverse.append(p.y, p.x, eps);
- appended = true;
- } else if (p.y < inverse.points_.front().x) {
- inverse.prepend(p.y, p.x, eps);
- prepended = true;
- } else
- neither = true;
- }
-
- /*
- * This is not a proper inverse if we found ourselves putting points
- * onto both ends of the inverse, or if there were points that couldn't
- * go on either.
- */
- if (trueInverse)
- *trueInverse = !(neither || (appended && prepended));
-
- return inverse;
-}
-
-Pwl Pwl::compose(Pwl const &other, const double eps) const
-{
- double thisX = points_[0].x, thisY = points_[0].y;
- int thisSpan = 0, otherSpan = other.findSpan(thisY, 0);
- Pwl result({ { thisX, other.eval(thisY, &otherSpan, false) } });
- while (thisSpan != (int)points_.size() - 1) {
- double dx = points_[thisSpan + 1].x - points_[thisSpan].x,
- dy = points_[thisSpan + 1].y - points_[thisSpan].y;
- if (std::abs(dy) > eps &&
- otherSpan + 1 < (int)other.points_.size() &&
- points_[thisSpan + 1].y >=
- other.points_[otherSpan + 1].x + eps) {
- /*
- * next control point in result will be where this
- * function's y reaches the next span in other
- */
- thisX = points_[thisSpan].x +
- (other.points_[otherSpan + 1].x -
- points_[thisSpan].y) *
- dx / dy;
- thisY = other.points_[++otherSpan].x;
- } else if (std::abs(dy) > eps && otherSpan > 0 &&
- points_[thisSpan + 1].y <=
- other.points_[otherSpan - 1].x - eps) {
- /*
- * next control point in result will be where this
- * function's y reaches the previous span in other
- */
- thisX = points_[thisSpan].x +
- (other.points_[otherSpan + 1].x -
- points_[thisSpan].y) *
- dx / dy;
- thisY = other.points_[--otherSpan].x;
- } else {
- /* we stay in the same span in other */
- thisSpan++;
- thisX = points_[thisSpan].x,
- thisY = points_[thisSpan].y;
- }
- result.append(thisX, other.eval(thisY, &otherSpan, false),
- eps);
- }
- return result;
-}
-
-void Pwl::map(std::function<void(double x, double y)> f) const
-{
- for (auto &pt : points_)
- f(pt.x, pt.y);
-}
-
-void Pwl::map2(Pwl const &pwl0, Pwl const &pwl1,
- std::function<void(double x, double y0, double y1)> f)
-{
- int span0 = 0, span1 = 0;
- double x = std::min(pwl0.points_[0].x, pwl1.points_[0].x);
- f(x, pwl0.eval(x, &span0, false), pwl1.eval(x, &span1, false));
- while (span0 < (int)pwl0.points_.size() - 1 ||
- span1 < (int)pwl1.points_.size() - 1) {
- if (span0 == (int)pwl0.points_.size() - 1)
- x = pwl1.points_[++span1].x;
- else if (span1 == (int)pwl1.points_.size() - 1)
- x = pwl0.points_[++span0].x;
- else if (pwl0.points_[span0 + 1].x > pwl1.points_[span1 + 1].x)
- x = pwl1.points_[++span1].x;
- else
- x = pwl0.points_[++span0].x;
- f(x, pwl0.eval(x, &span0, false), pwl1.eval(x, &span1, false));
- }
-}
-
-Pwl Pwl::combine(Pwl const &pwl0, Pwl const &pwl1,
- std::function<double(double x, double y0, double y1)> f,
- const double eps)
-{
- Pwl result;
- map2(pwl0, pwl1, [&](double x, double y0, double y1) {
- result.append(x, f(x, y0, y1), eps);
- });
- return result;
-}
-
-void Pwl::matchDomain(Interval const &domain, bool clip, const double eps)
-{
- int span = 0;
- prepend(domain.start, eval(clip ? points_[0].x : domain.start, &span),
- eps);
- span = points_.size() - 2;
- append(domain.end, eval(clip ? points_.back().x : domain.end, &span),
- eps);
-}
-
-Pwl &Pwl::operator*=(double d)
-{
- for (auto &pt : points_)
- pt.y *= d;
- return *this;
-}
-
-void Pwl::debug(FILE *fp) const
-{
- fprintf(fp, "Pwl {\n");
- for (auto &p : points_)
- fprintf(fp, "\t(%g, %g)\n", p.x, p.y);
- fprintf(fp, "}\n");
-}