ipa: rpi: controller: Use libipa's Pwl class

To reduce code duplication, use the Pwl class from libipa. This also
removes the Pwl class from the Raspberry Pi IPA.

Signed-off-by: Paul Elder <paul.elder@ideasonboard.com>
Reviewed-by: Stefan Klug <stefan.klug@ideasonboard.com>
Acked-by: David Plowman <david.plowman@raspberrypi.com>
Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>

1 files changed, 0 insertions, 269 deletions

diff --git a/src/ipa/rpi/controller/pwl.cpp b/src/ipa/rpi/controller/pwl.cpp
deleted file mode 100644
index e3912376..00000000
--- a/src/ipa/rpi/controller/pwl.cpp
+++ /dev/null
@@ -1,269 +0,0 @@
-/* SPDX-License-Identifier: BSD-2-Clause */
-/*
- * Copyright (C) 2019, Raspberry Pi Ltd
- *
- * 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");
-}