move evoral/src/* to evoral/

libs/evoral/Curve.cc

@@ -0,0 +1,458 @@
+/*
+ * Copyright (C) 2008-2013 Paul Davis <paul@linuxaudiosystems.com>
+ * Copyright (C) 2008-2016 David Robillard <d@drobilla.net>
+ * Copyright (C) 2010-2012 Carl Hetherington <carl@carlh.net>
+ * Copyright (C) 2012-2018 Robin Gareus <robin@gareus.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#include <iostream>
+#include <float.h>
+#include <cmath>
+#include <climits>
+#include <cfloat>
+#include <cmath>
+#include <vector>
+
+#include <glibmm/threads.h>
+
+#include "pbd/control_math.h"
+
+#include "evoral/Curve.h"
+#include "evoral/ControlList.h"
+
+using namespace std;
+using namespace sigc;
+
+namespace Evoral {
+
+
+Curve::Curve (const ControlList& cl)
+	: _dirty (true)
+	, _list (cl)
+{
+}
+
+void
+Curve::solve () const
+{
+	uint32_t npoints;
+
+	if (!_dirty) {
+		return;
+	}
+
+	if ((npoints = _list.events().size()) > 2) {
+
+		/* Compute coefficients needed to efficiently compute a constrained spline
+		   curve. See "Constrained Cubic Spline Interpolation" by CJC Kruger
+		   (www.korf.co.uk/spline.pdf) for more details.
+		*/
+
+		vector<double> x(npoints);
+		vector<double> y(npoints);
+		uint32_t i;
+		ControlList::EventList::const_iterator xx;
+
+		for (i = 0, xx = _list.events().begin(); xx != _list.events().end(); ++xx, ++i) {
+			x[i] = (double) (*xx)->when;
+			y[i] = (double) (*xx)->value;
+		}
+
+		double lp0, lp1, fpone;
+
+		lp0 = (x[1] - x[0])/(y[1] - y[0]);
+		lp1 = (x[2] - x[1])/(y[2] - y[1]);
+
+		if (lp0*lp1 < 0) {
+			fpone = 0;
+		} else {
+			fpone = 2 / (lp1 + lp0);
+		}
+
+		double fplast = 0;
+
+		for (i = 0, xx = _list.events().begin(); xx != _list.events().end(); ++xx, ++i) {
+
+			double xdelta;   /* gcc is wrong about possible uninitialized use */
+			double xdelta2;  /* ditto */
+			double ydelta;   /* ditto */
+			double fppL, fppR;
+			double fpi;
+
+			if (i > 0) {
+				xdelta = x[i] - x[i-1];
+				xdelta2 = xdelta * xdelta;
+				ydelta = y[i] - y[i-1];
+			}
+
+			/* compute (constrained) first derivatives */
+
+			if (i == 0) {
+
+				/* first segment */
+
+				fplast = ((3 * (y[1] - y[0]) / (2 * (x[1] - x[0]))) - (fpone * 0.5));
+
+				/* we don't store coefficients for i = 0 */
+
+				continue;
+
+			} else if (i == npoints - 1) {
+
+				/* last segment */
+
+				fpi = ((3 * ydelta) / (2 * xdelta)) - (fplast * 0.5);
+
+			} else {
+
+				/* all other segments */
+
+				double slope_before = ((x[i+1] - x[i]) / (y[i+1] - y[i]));
+				double slope_after = (xdelta / ydelta);
+
+				if (slope_after * slope_before < 0.0) {
+					/* slope changed sign */
+					fpi = 0.0;
+				} else {
+					fpi = 2 / (slope_before + slope_after);
+				}
+			}
+
+			/* compute second derivative for either side of control point `i' */
+
+			fppL = (((-2 * (fpi + (2 * fplast))) / (xdelta))) +
+				((6 * ydelta) / xdelta2);
+
+			fppR = (2 * ((2 * fpi) + fplast) / xdelta) -
+				((6 * ydelta) / xdelta2);
+
+			/* compute polynomial coefficients */
+
+			double b, c, d;
+
+			d = (fppR - fppL) / (6 * xdelta);
+			c = ((x[i] * fppL) - (x[i-1] * fppR))/(2 * xdelta);
+
+			double xim12, xim13;
+			double xi2, xi3;
+
+			xim12 = x[i-1] * x[i-1];  /* "x[i-1] squared" */
+			xim13 = xim12 * x[i-1];   /* "x[i-1] cubed" */
+			xi2 = x[i] * x[i];        /* "x[i] squared" */
+			xi3 = xi2 * x[i];         /* "x[i] cubed" */
+
+			b = (ydelta - (c * (xi2 - xim12)) - (d * (xi3 - xim13))) / xdelta;
+
+			/* store */
+
+			(*xx)->create_coeffs();
+			(*xx)->coeff[0] = y[i-1] - (b * x[i-1]) - (c * xim12) - (d * xim13);
+			(*xx)->coeff[1] = b;
+			(*xx)->coeff[2] = c;
+			(*xx)->coeff[3] = d;
+
+			fplast = fpi;
+		}
+
+	}
+
+	_dirty = false;
+}
+
+bool
+Curve::rt_safe_get_vector (double x0, double x1, float *vec, int32_t veclen) const
+{
+	Glib::Threads::RWLock::ReaderLock lm(_list.lock(), Glib::Threads::TRY_LOCK);
+
+	if (!lm.locked()) {
+		return false;
+	} else {
+		_get_vector (x0, x1, vec, veclen);
+		return true;
+	}
+}
+
+void
+Curve::get_vector (double x0, double x1, float *vec, int32_t veclen) const
+{
+	Glib::Threads::RWLock::ReaderLock lm(_list.lock());
+	_get_vector (x0, x1, vec, veclen);
+}
+
+void
+Curve::_get_vector (double x0, double x1, float *vec, int32_t veclen) const
+{
+	double rx, lx, hx, max_x, min_x;
+	int32_t i;
+	int32_t original_veclen;
+	int32_t npoints;
+
+	if (veclen == 0) {
+		return;
+	}
+
+	if ((npoints = _list.events().size()) == 0) {
+		/* no events in list, so just fill the entire array with the default value */
+		for (int32_t i = 0; i < veclen; ++i) {
+			vec[i] = _list.descriptor().normal;
+		}
+		return;
+	}
+
+	if (npoints == 1) {
+		for (int32_t i = 0; i < veclen; ++i) {
+			vec[i] = _list.events().front()->value;
+		}
+		return;
+	}
+
+	/* events is now known not to be empty */
+
+	max_x = _list.events().back()->when;
+	min_x = _list.events().front()->when;
+
+	if (x0 > max_x) {
+		/* totally past the end - just fill the entire array with the final value */
+		for (int32_t i = 0; i < veclen; ++i) {
+			vec[i] = _list.events().back()->value;
+		}
+		return;
+	}
+
+	if (x1 < min_x) {
+		/* totally before the first event - fill the entire array with
+		 * the initial value.
+		 */
+		for (int32_t i = 0; i < veclen; ++i) {
+			vec[i] = _list.events().front()->value;
+		}
+		return;
+	}
+
+	original_veclen = veclen;
+
+	if (x0 < min_x) {
+
+		/* fill some beginning section of the array with the
+		   initial (used to be default) value
+		*/
+
+		double frac = (min_x - x0) / (x1 - x0);
+		int64_t fill_len = (int64_t) floor (veclen * frac);
+
+		fill_len = min (fill_len, (int64_t)veclen);
+
+		for (i = 0; i < fill_len; ++i) {
+			vec[i] = _list.events().front()->value;
+		}
+
+		veclen -= fill_len;
+		vec += fill_len;
+	}
+
+	if (veclen && x1 > max_x) {
+
+		/* fill some end section of the array with the default or final value */
+
+		double frac = (x1 - max_x) / (x1 - x0);
+		int64_t fill_len = (int64_t) floor (original_veclen * frac);
+		float val;
+
+		fill_len = min (fill_len, (int64_t)veclen);
+		val = _list.events().back()->value;
+
+		for (i = veclen - fill_len; i < veclen; ++i) {
+			vec[i] = val;
+		}
+
+		veclen -= fill_len;
+	}
+
+	lx = max (min_x, x0);
+	hx = min (max_x, x1);
+
+	if (npoints == 2) {
+
+		const double lpos = _list.events().front()->when;
+		const double lval = _list.events().front()->value;
+		const double upos = _list.events().back()->when;
+		const double uval = _list.events().back()->value;
+
+		/* dx that we are using */
+		if (veclen > 1) {
+			const double dx_num = hx - lx;
+			const double dx_den = veclen - 1;
+			const double lower = _list.descriptor().lower;
+			const double upper = _list.descriptor().upper;
+
+			/* gradient of the line */
+			const double m_num = uval - lval;
+			const double m_den = upos - lpos;
+			/* y intercept of the line */
+			const double c = uval - (m_num * upos / m_den);
+
+			switch (_list.interpolation()) {
+				case ControlList::Logarithmic:
+					for (int i = 0; i < veclen; ++i) {
+						const double fraction = (lx - lpos + i * dx_num / dx_den) / m_den;
+						vec[i] = interpolate_logarithmic (lval, uval, fraction, lower, upper);
+					}
+					break;
+				case ControlList::Exponential:
+					for (int i = 0; i < veclen; ++i) {
+						const double fraction = (lx - lpos + i * dx_num / dx_den) / m_den;
+						vec[i] = interpolate_gain (lval, uval, fraction, upper);
+					}
+					break;
+				case ControlList::Discrete:
+					// any discrete vector curves somewhere?
+					assert (0);
+				case ControlList::Curved:
+					/* no 2 point spline */
+					/* fallthrough */
+				default: // Linear:
+					for (int i = 0; i < veclen; ++i) {
+						vec[i] = (lx * (m_num / m_den) + m_num * i * dx_num / (m_den * dx_den)) + c;
+					}
+					break;
+			}
+		} else {
+			double fraction = (lx - lpos) / (upos - lpos);
+			switch (_list.interpolation()) {
+				case ControlList::Logarithmic:
+					vec[0] = interpolate_logarithmic (lval, uval, fraction, _list.descriptor().lower, _list.descriptor().upper);
+					break;
+				case ControlList::Exponential:
+					vec[0] = interpolate_gain (lval, uval, fraction, _list.descriptor().upper);
+					break;
+				case ControlList::Discrete:
+					// any discrete vector curves somewhere?
+					assert (0);
+				case ControlList::Curved:
+					/* no 2 point spline */
+					/* fallthrough */
+				default: // Linear:
+					vec[0] = interpolate_linear (lval, uval, fraction);
+					break;
+			}
+		}
+
+		return;
+	}
+
+	if (_dirty) {
+		solve ();
+	}
+
+	rx = lx;
+
+	double dx = 0;
+	if (veclen > 1) {
+		dx = (hx - lx) / (veclen - 1);
+	}
+
+	for (i = 0; i < veclen; ++i, rx += dx) {
+		vec[i] = multipoint_eval (rx);
+	}
+}
+
+double
+Curve::multipoint_eval (double x) const
+{
+	pair<ControlList::EventList::const_iterator,ControlList::EventList::const_iterator> range;
+
+	ControlList::LookupCache& lookup_cache = _list.lookup_cache();
+
+	if ((lookup_cache.left < 0) ||
+	    ((lookup_cache.left > x) ||
+	     (lookup_cache.range.first == _list.events().end()) ||
+	     ((*lookup_cache.range.second)->when < x))) {
+
+		ControlEvent cp (x, 0.0);
+
+		lookup_cache.range = equal_range (_list.events().begin(), _list.events().end(), &cp, ControlList::time_comparator);
+	}
+
+	range = lookup_cache.range;
+
+	/* EITHER
+
+	   a) x is an existing control point, so first == existing point, second == next point
+
+	   OR
+
+	   b) x is between control points, so range is empty (first == second, points to where
+	       to insert x)
+
+	*/
+
+	if (range.first == range.second) {
+
+		/* x does not exist within the list as a control point */
+
+		lookup_cache.left = x;
+
+		if (range.first == _list.events().begin()) {
+			/* we're before the first point */
+			// return default_value;
+			return _list.events().front()->value;
+		}
+
+		if (range.second == _list.events().end()) {
+			/* we're after the last point */
+			return _list.events().back()->value;
+		}
+
+		ControlEvent* after = (*range.second);
+		range.second--;
+		ControlEvent* before = (*range.second);
+
+		double vdelta = after->value - before->value;
+
+		if (vdelta == 0.0) {
+			return before->value;
+		}
+
+		double tdelta = x - before->when;
+		double trange = after->when - before->when;
+
+		switch (_list.interpolation()) {
+			case ControlList::Discrete:
+				return before->value;
+			case ControlList::Logarithmic:
+				return interpolate_logarithmic (before->value, after->value, tdelta / trange, _list.descriptor().lower, _list.descriptor().upper);
+			case ControlList::Exponential:
+				return interpolate_gain (before->value, after->value, tdelta / trange, _list.descriptor().upper);
+			case ControlList::Curved:
+				if (after->coeff) {
+					ControlEvent* ev = after;
+					double x2 = x * x;
+					return ev->coeff[0] + (ev->coeff[1] * x) + (ev->coeff[2] * x2) + (ev->coeff[3] * x2 * x);
+				}
+				/* fallthrough */
+			case ControlList::Linear:
+				return before->value + (vdelta * (tdelta / trange));
+		}
+	}
+
+	/* x is a control point in the data */
+	/* invalidate the cached range because its not usable */
+	lookup_cache.left = -1;
+	return (*range.first)->value;
+}
+
+} // namespace Evoral