From patchwork Fri Jun 7 07:57:13 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Paul Elder X-Patchwork-Id: 20226 Return-Path: X-Original-To: parsemail@patchwork.libcamera.org Delivered-To: parsemail@patchwork.libcamera.org Received: from lancelot.ideasonboard.com (lancelot.ideasonboard.com [92.243.16.209]) by patchwork.libcamera.org (Postfix) with ESMTPS id 6A780BD87C for ; Fri, 7 Jun 2024 07:57:41 +0000 (UTC) Received: from lancelot.ideasonboard.com (localhost [IPv6:::1]) by lancelot.ideasonboard.com (Postfix) with ESMTP id 1332D65466; Fri, 7 Jun 2024 09:57:41 +0200 (CEST) Authentication-Results: lancelot.ideasonboard.com; dkim=pass (1024-bit key; unprotected) header.d=ideasonboard.com header.i=@ideasonboard.com header.b="DLel5Mcj"; dkim-atps=neutral Received: from perceval.ideasonboard.com (perceval.ideasonboard.com [IPv6:2001:4b98:dc2:55:216:3eff:fef7:d647]) by lancelot.ideasonboard.com (Postfix) with ESMTPS id 76DAF65461 for ; Fri, 7 Jun 2024 09:57:36 +0200 (CEST) Received: from neptunite.hamster-moth.ts.net (h175-177-049-156.catv02.itscom.jp [175.177.49.156]) by perceval.ideasonboard.com (Postfix) with ESMTPSA id 2638A1495; Fri, 7 Jun 2024 09:57:24 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com; s=mail; t=1717747046; bh=0c7RxijGHvO0PNuNwPKj0QBiEbMGdGlptiS68ujmsq4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=DLel5Mcj3ZlLp3z/GSkR0U61zBHwwxW/WW3Z41loKcAJgneiB1UYJ9CeQ0we45lXd RJSJoY/IhvAHxnNApDkOsxyisVmOK8nvYEFxx+0bvg6SGp6RfZC+nX1SavokaYQI3w tiDsnilZr1nZSoDAdChRnvpNKoxHTv5IcSmqwjbo= From: Paul Elder To: libcamera-devel@lists.libcamera.org Cc: Paul Elder , Stefan Klug , David Plowman Subject: [PATCH v5 3/4] ipa: libipa: pwl: Clean up Pwl class to match libcamera Date: Fri, 7 Jun 2024 16:57:13 +0900 Message-Id: <20240607075714.2648851-4-paul.elder@ideasonboard.com> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20240607075714.2648851-1-paul.elder@ideasonboard.com> References: <20240607075714.2648851-1-paul.elder@ideasonboard.com> MIME-Version: 1.0 X-BeenThere: libcamera-devel@lists.libcamera.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: libcamera-devel-bounces@lists.libcamera.org Sender: "libcamera-devel" Clean up the Pwl class copied from the Raspberry Pi IPA to align it more with the libcamera style. Signed-off-by: Paul Elder Reviewed-by: Stefan Klug Acked-by: David Plowman --- Changes in v5: - fix documentation order - fix some typos - add the Vector-based PointF Changes in v4: - update to apply to new copy of pwl - add documentation - fix doxygen No change in v3 Changes in v2: - s/FPoint/PointF/g - improve documentation - s/matchDomain/extendDomain/ --- src/ipa/libipa/pwl.cpp | 365 +++++++++++++++++++++++++++++++++-------- src/ipa/libipa/pwl.h | 123 ++++++-------- 2 files changed, 342 insertions(+), 146 deletions(-) diff --git a/src/ipa/libipa/pwl.cpp b/src/ipa/libipa/pwl.cpp index e39123767..8f8ee17e8 100644 --- a/src/ipa/libipa/pwl.cpp +++ b/src/ipa/libipa/pwl.cpp @@ -1,19 +1,120 @@ /* SPDX-License-Identifier: BSD-2-Clause */ /* * Copyright (C) 2019, Raspberry Pi Ltd + * Copyright (C) 2024, Ideas on Board Oy * - * piecewise linear functions + * Piecewise linear functions */ +#include "pwl.h" + #include #include +#include #include -#include "pwl.h" +#include + +/** + * \file pwl.h + * \brief Piecewise linear functions + */ + +namespace libcamera { + +namespace ipa { + +/** + * \class Pwl + * \brief Describe a univariate piecewise linear function in real space + */ + +/** + * \typedef Pwl::PointF + * \brief Describe a point in two-dimensional real space + */ + +/** + * \enum Pwl::PerpType + * \brief Type of perpendicular found when inverting a piecewise linear function + * + * \var Pwl::PerpType::None + * \brief No perpendicular found + * + * \var Pwl::PerpType::Start + * \brief Start of Pwl is closest point + * + * \var Pwl::PerpType::End + * \brief End of Pwl is closest point + * + * \var Pwl::PerpType::Vertex + * \brief Vertex of Pwl is closest point + * + * \var Pwl::PerpType::Perpendicular + * \brief True perpendicular found + */ -using namespace RPiController; +/** + * \class Pwl::Interval + * \brief Describe an interval in one-dimensional real space + */ + +/** + * \fn Pwl::Interval::Interval(double _start, double _end) + * \brief Construct an interval + * \param _start Start of the interval + * \param _end End of the interval + */ + +/** + * \fn Pwl::Interval::contains + * \brief Check if a given value falls within the interval + * \param value Value to check + */ + +/** + * \fn Pwl::Interval::clamp + * \brief Clamp a value such that it is within the interval + * \param value Value to clamp + */ + +/** + * \fn Pwl::Interval::len + * \brief Compute the length of the interval + */ -int Pwl::read(const libcamera::YamlObject ¶ms) +/** + * \var Pwl::Interval::start + * \brief Start of the interval + */ + +/** + * \var Pwl::Interval::end + * \brief End of the interval + */ + +/** + * \fn Pwl::Pwl(std::vector const &points) + * \brief Construct a piecewise linear function from a list of 2D points + * \param points Vector of points from which to construct the piecewise linear function + * + * \a points must be in ascending order of x-value. + */ + +/** + * \brief Populate the piecewise linear function from yaml data + * \param params Yaml data to populate the piecewise linear function with + * + * Any existing points in the piecewise linear function will *not* be + * overwritten. + * + * The yaml data is expected to be a list with an even number of numerical + * elements. These will be parsed in pairs into x and y points in the piecewise + * linear function, and added in order. x must be monotonically increasing. + * + * \return 0 on success, negative error code otherwise + */ +int Pwl::readYaml(const libcamera::YamlObject ¶ms) { if (!params.size() || params.size() % 2) return -EINVAL; @@ -24,64 +125,109 @@ int Pwl::read(const libcamera::YamlObject ¶ms) auto x = it->get(); if (!x) return -EINVAL; - if (it != list.begin() && *x <= points_.back().x) + if (it != list.begin() && *x <= points_.back().x()) return -EINVAL; auto y = (++it)->get(); if (!y) return -EINVAL; - points_.push_back(Point(*x, *y)); + points_.push_back(PointF({ *x, *y })); } return 0; } +/** + * \brief Append a point to the end of the piecewise linear function + * \param x x-coordinate of the point to add to the piecewise linear function + * \param y y-coordinate of the point to add to the piecewise linear function + * \param eps Epsilon for the minimum x distance between points (optional) + * + * The point's x-coordinate must be greater than the x-coordinate of the last + * (= greatest) point already in the piecewise linear function. + */ void Pwl::append(double x, double y, const double eps) { - if (points_.empty() || points_.back().x + eps < x) - points_.push_back(Point(x, y)); + if (points_.empty() || points_.back().x() + eps < x) + points_.push_back(PointF({ x, y })); } +/** + * \brief Prepend a point to the beginning of the piecewise linear function + * \param x x-coordinate of the point to add to the piecewise linear function + * \param y y-coordinate of the point to add to the piecewise linear function + * \param eps Epsilon for the minimum x distance between points (optional) + * + * The point's x-coordinate must be less than the x-coordinate of the first + * (= smallest) point already in the piecewise linear function. + */ 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)); + if (points_.empty() || points_.front().x() - eps > x) + points_.insert(points_.begin(), PointF({ x, y })); } +/** + * \brief Get the domain of the piecewise linear function + * \return An interval representing the domain + */ Pwl::Interval Pwl::domain() const { - return Interval(points_[0].x, points_[points_.size() - 1].x); + return Interval(points_[0].x(), points_[points_.size() - 1].x()); } +/** + * \brief Get the range of the piecewise linear function + * \return An interval representing the range + */ Pwl::Interval Pwl::range() const { - double lo = points_[0].y, hi = lo; + double lo = points_[0].y(), hi = lo; for (auto &p : points_) - lo = std::min(lo, p.y), hi = std::max(hi, p.y); + lo = std::min(lo, p.y()), hi = std::max(hi, p.y()); return Interval(lo, hi); } +/** + * \brief Check if the piecewise linear function is empty + * \return True if there are no points in the function, false otherwise + */ bool Pwl::empty() const { return points_.empty(); } +/** + * \brief Evaluate the piecewise linear function + * \param[in] x The x value to input into the function + * \param[inout] spanPtr Initial guess for span + * \param[in] updateSpan Set to true to update spanPtr + * + * Evaluate Pwl, optionally supplying an initial guess for the + * "span". The "span" may be optionally be updated. If you want to know + * the "span" value but don't have an initial guess you can set it to + * -1. + * + * \return The result of evaluating the piecewise linear function at position \a x + */ double Pwl::eval(double x, int *spanPtr, bool updateSpan) const { - int span = findSpan(x, spanPtr && *spanPtr != -1 ? *spanPtr : points_.size() / 2 - 1); + 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); + 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. + * binary, though could review this if large Pwls start turning up. */ int lastSpan = points_.size() - 2; /* @@ -89,23 +235,36 @@ int Pwl::findSpan(double x, int span) const * control point */ span = std::max(0, std::min(lastSpan, span)); - while (span < lastSpan && x >= points_[span + 1].x) + while (span < lastSpan && x >= points_[span + 1].x()) span++; - while (span && x < points_[span].x) + while (span && x < points_[span].x()) span--; return span; } -Pwl::PerpType Pwl::invert(Point const &xy, Point &perp, int &span, +/** + * \brief Find perpendicular closest to a given point + * \param[in] xy Point to find the perpendicular to + * \param[out] perp The found perpendicular + * \param[inout] span The span left of the point to start searching from + * \param[in] eps Epsilon for the minimum x distance between points (optional) + * + * Find perpendicular closest to \a xy, starting from \a span+1 so you can call + * it repeatedly to check for multiple closest points (set span to -1 on the + * first call). Also returns "pseudo" perpendiculars; see PerpType enum. + * + * \return Type of perpendicular found + */ +Pwl::PerpType Pwl::invert(PointF const &xy, PointF &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 */ - { + PointF 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; @@ -113,15 +272,15 @@ Pwl::PerpType Pwl::invert(Point const &xy, Point &perp, int &span, perp = points_[span]; return PerpType::Vertex; } - } else if (t > 1 + eps) /* off the end of this span */ - { + } 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 */ - { + } else { + /* a true perpendicular */ perp = points_[span] + spanVec * t; return PerpType::Perpendicular; } @@ -129,25 +288,36 @@ Pwl::PerpType Pwl::invert(Point const &xy, Point &perp, int &span, return PerpType::None; } +/** + * \brief Compute the inverse function + * \param[out] trueInverse True if the result is a proper/true inverse + * \param[in] eps Epsilon for the minimum x distance between points (optional) + * + * Indicate if it is a proper (true) inverse, or only a best effort (e.g. + * input was non-monotonic). + * + * \return The inverse piecewise linear function + */ 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) + for (PointF 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); + } 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); + } else if (p.y() < inverse.points_.front().x()) { + inverse.prepend(p.y(), p.x(), eps); prepended = true; - } else + } else { neither = true; + } } /* @@ -161,44 +331,53 @@ Pwl Pwl::inverse(bool *trueInverse, const double eps) const return inverse; } +/** + * \brief Compose two piecewise linear functions together + * \param[in] other The "other" piecewise linear function + * \param[in] eps Epsilon for the minimum x distance between points (optional) + * + * The "this" function is done first, and "other" after. + * + * \return The composed piecewise linear function + */ Pwl Pwl::compose(Pwl const &other, const double eps) const { - double thisX = points_[0].x, thisY = points_[0].y; + 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) } }); + Pwl result({ PointF({ 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; + 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) { + 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) * + thisX = points_[thisSpan].x() + + (other.points_[otherSpan + 1].x() - + points_[thisSpan].y()) * dx / dy; - thisY = other.points_[++otherSpan].x; + thisY = other.points_[++otherSpan].x(); } else if (std::abs(dy) > eps && otherSpan > 0 && - points_[thisSpan + 1].y <= - other.points_[otherSpan - 1].x - eps) { + 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) * + thisX = points_[thisSpan].x() + + (other.points_[otherSpan + 1].x() - + points_[thisSpan].y()) * dx / dy; - thisY = other.points_[--otherSpan].x; + thisY = other.points_[--otherSpan].x(); } else { /* we stay in the same span in other */ thisSpan++; - thisX = points_[thisSpan].x, - thisY = points_[thisSpan].y; + thisX = points_[thisSpan].x(), + thisY = points_[thisSpan].y(); } result.append(thisX, other.eval(thisY, &otherSpan, false), eps); @@ -206,32 +385,47 @@ Pwl Pwl::compose(Pwl const &other, const double eps) const return result; } +/** + * \brief Apply function to (x,y) values at every control point + * \param f Function to be applied + */ void Pwl::map(std::function f) const { for (auto &pt : points_) - f(pt.x, pt.y); + f(pt.x(), pt.y()); } +/** + * \brief Apply function to (x, y0, y1) values wherever either Pwl has a + * control point. + */ void Pwl::map2(Pwl const &pwl0, Pwl const &pwl1, std::function f) { int span0 = 0, span1 = 0; - double x = std::min(pwl0.points_[0].x, pwl1.points_[0].x); + 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; + 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; + 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; + x = pwl0.points_[++span0].x(); f(x, pwl0.eval(x, &span0, false), pwl1.eval(x, &span1, false)); } } +/** + * \brief Combine two Pwls + * + * Create a new Pwl where the y values are given by running f wherever either + * has a knot. + */ Pwl Pwl::combine(Pwl const &pwl0, Pwl const &pwl1, std::function f, const double eps) @@ -243,27 +437,54 @@ Pwl Pwl::combine(Pwl const &pwl0, Pwl const &pwl1, return result; } -void Pwl::matchDomain(Interval const &domain, bool clip, const double eps) +/** + * \brief Extend the domain of the piecewise linear function + * \param[in] domain The domain to extend to + * \param[in] clip True to keep the existing edge y values, false to extrapolate + * \param[in] eps Epsilon for the minimum x distance between points (optional) + * + * Extend the domain of the piecewise linear function to match \a domain. If \a + * clip is set to true then the y values of the new edges will be the same as + * the existing y values of the edge points of the pwl. If false, then the y + * values will be extrapolated linearly from the existing edge points of the + * pwl. + */ +void Pwl::extendDomain(Interval const &domain, bool clip, const double eps) { int span = 0; - prepend(domain.start, eval(clip ? points_[0].x : domain.start, &span), + 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), + append(domain.end, eval(clip ? points_.back().x() : domain.end, &span), eps); } +/** + * \brief Multiply the piecewise linear function + * \param d Scalar multiplier to multiply the function by + * \return This function, after it has been multiplied by \a d + */ Pwl &Pwl::operator*=(double d) { for (auto &pt : points_) - pt.y *= d; + pt[1] *= d; return *this; } -void Pwl::debug(FILE *fp) const +/** + * \brief Assemble and return a string describing the piecewise linear function + * \return A string describing the piecewise linear function + */ +std::string Pwl::toString() const { - fprintf(fp, "Pwl {\n"); + std::stringstream ss; + ss << "Pwl { "; for (auto &p : points_) - fprintf(fp, "\t(%g, %g)\n", p.x, p.y); - fprintf(fp, "}\n"); + ss << "(" << p.x() << ", " << p.y() << ") "; + ss << "}"; + return ss.str(); } + +} /* namespace ipa */ + +} /* namespace libcamera */ diff --git a/src/ipa/libipa/pwl.h b/src/ipa/libipa/pwl.h index 7d5e7e4d3..c73693341 100644 --- a/src/ipa/libipa/pwl.h +++ b/src/ipa/libipa/pwl.h @@ -2,126 +2,101 @@ /* * Copyright (C) 2019, Raspberry Pi Ltd * - * piecewise linear functions interface + * Piecewise linear functions interface */ #pragma once #include #include +#include #include +#include + #include "libcamera/internal/yaml_parser.h" -namespace RPiController { +#include "vector.h" + +namespace libcamera { + +namespace ipa { class Pwl { public: + using PointF = Vector; + + enum class PerpType { + None, + Start, + End, + Vertex, + Perpendicular, + }; + struct Interval { Interval(double _start, double _end) - : start(_start), end(_end) - { - } - double start, end; + : start(_start), end(_end) {} + bool contains(double value) { return value >= start && value <= end; } - double clip(double value) + + double clamp(double value) { return value < start ? start : (value > end ? end : value); } + double len() const { return end - start; } + + double start, end; }; - struct Point { - Point() : x(0), y(0) {} - Point(double _x, double _y) - : x(_x), y(_y) {} - double x, y; - Point operator-(Point const &p) const - { - return Point(x - p.x, y - p.y); - } - Point operator+(Point const &p) const - { - return Point(x + p.x, y + p.y); - } - double operator%(Point const &p) const - { - return x * p.x + y * p.y; - } - Point operator*(double f) const { return Point(x * f, y * f); } - Point operator/(double f) const { return Point(x / f, y / f); } - double len2() const { return x * x + y * y; } - double len() const { return sqrt(len2()); } - }; + Pwl() {} - Pwl(std::vector const &points) : points_(points) {} - int read(const libcamera::YamlObject ¶ms); + Pwl(std::vector const &points) + : points_(points) {} + int readYaml(const libcamera::YamlObject ¶ms); + void append(double x, double y, const double eps = 1e-6); void prepend(double x, double y, const double eps = 1e-6); + Interval domain() const; Interval range() const; + bool empty() const; - /* - * Evaluate Pwl, optionally supplying an initial guess for the - * "span". The "span" may be optionally be updated. If you want to know - * the "span" value but don't have an initial guess you can set it to - * -1. - */ + double eval(double x, int *spanPtr = nullptr, bool updateSpan = true) const; - /* - * Find perpendicular closest to xy, starting from span+1 so you can - * call it repeatedly to check for multiple closest points (set span to - * -1 on the first call). Also returns "pseudo" perpendiculars; see - * PerpType enum. - */ - enum class PerpType { - None, /* no perpendicular found */ - Start, /* start of Pwl is closest point */ - End, /* end of Pwl is closest point */ - Vertex, /* vertex of Pwl is closest point */ - Perpendicular /* true perpendicular found */ - }; - PerpType invert(Point const &xy, Point &perp, int &span, + + PerpType invert(PointF const &xy, PointF &perp, int &span, const double eps = 1e-6) const; - /* - * Compute the inverse function. Indicate if it is a proper (true) - * inverse, or only a best effort (e.g. input was non-monotonic). - */ Pwl inverse(bool *trueInverse = nullptr, const double eps = 1e-6) const; - /* Compose two Pwls together, doing "this" first and "other" after. */ Pwl compose(Pwl const &other, const double eps = 1e-6) const; - /* Apply function to (x,y) values at every control point. */ + void map(std::function f) const; - /* - * Apply function to (x, y0, y1) values wherever either Pwl has a - * control point. - */ + static void map2(Pwl const &pwl0, Pwl const &pwl1, std::function f); - /* - * Combine two Pwls, meaning we create a new Pwl where the y values are - * given by running f wherever either has a knot. - */ + static Pwl combine(Pwl const &pwl0, Pwl const &pwl1, std::function f, const double eps = 1e-6); - /* - * Make "this" match (at least) the given domain. Any extension my be - * clipped or linear. - */ - void matchDomain(Interval const &domain, bool clip = true, - const double eps = 1e-6); + + void extendDomain(Interval const &domain, bool clip = true, + const double eps = 1e-6); + Pwl &operator*=(double d); - void debug(FILE *fp = stdout) const; + + std::string toString() const; private: int findSpan(double x, int span) const; - std::vector points_; + std::vector points_; }; -} /* namespace RPiController */ +} /* namespace ipa */ + +} /* namespace libcamera */