8b2eac9a3d
The pipette part is already working quite nice but need to be finished. The widgets part needs more work...
160 lines
4.9 KiB
C
160 lines
4.9 KiB
C
/*
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* This file is part of RawTherapee.
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*
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* Copyright (c) 2004-2010 Gabor Horvath <hgabor@rawtherapee.com>
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*
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* RawTherapee is free software: you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation, either version 3 of the License, or
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* (at your option) any later version.
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*
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* RawTherapee is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with RawTherapee. If not, see <http://www.gnu.org/licenses/>.
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*/
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inline double tightestroot (double L, double a, double b, double r1, double r2, double r3);
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#ifndef __COLORCLIP__
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#define __COLORCLIP__
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#include <cmath>
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#include "median.h"
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// gives back the tightest >0 amplification by which color clipping occures
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inline double tightestroot (double L, double a, double b, double r1, double r2, double r3) {
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double an = a/500.0, bn = b/200.0, p = (L+16.0)/116.0;
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double coeff3 = r1*an*an*an - r3*bn*bn*bn;
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double coeff2 = 3.0 * p * (r1*an*an + r3*bn*bn);
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double coeff1 = 3.0 * p*p * (r1*an - r3*bn);
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double coeff0 = p*p*p*(r1+r2+r3) - 1.0;
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double a1 = coeff2 / coeff3;
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double a2 = coeff1 / coeff3;
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double a3 = coeff0 / coeff3;
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double Q = (a1 * a1 - 3.0 * a2) / 9.0;
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double R = (2.0 * a1 * a1 * a1 - 9.0 * a1 * a2 + 27.0 * a3) / 54.0;
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double Qcubed = Q * Q * Q;
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double d = Qcubed - R * R;
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// printf ("input L=%g, a=%g, b=%g\n", L, a, b);
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// printf ("c1=%g, c2=%g, c3=%g, c4=%g\n", coeff3, coeff2, coeff1, coeff0);
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/* Three real roots */
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if (d >= 0) {
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double theta = acos(R / sqrt(Qcubed));
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double sqrtQ = sqrt(Q);
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double x0 = -2.0 * sqrtQ * cos( theta / 3.0) - a1 / 3.0;
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double x1 = -2.0 * sqrtQ * cos((theta + 2.0 * M_PI) / 3.0) - a1 / 3.0;
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double x2 = -2.0 * sqrtQ * cos((theta + 4.0 * M_PI) / 3.0) - a1 / 3.0;
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// printf ("3 roots: %g, %g, %g\n", x0, x1, x2);
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SORT3 (x0,x1,x2,a1,a2,a3);
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if (a1>0)
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return a1;
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if (a2>0)
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return a2;
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if (a3>0)
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return a3;
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return -1;
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}
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/* One real root */
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else {
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// double e = pow(sqrt(-d) + fabs(R), 1.0 / 3.0);
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double e = exp (1.0 / 3.0 * log (sqrt(-d) + fabs(R)));
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if (R > 0)
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e = -e;
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double x0 = (e + Q / e) - a1 / 3.0;
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// printf ("1 root: %g\n", x0);
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if (x0<0)
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return -1;
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else
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return x0;
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}
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}
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/*******************************************************************************
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* FindCubicRoots
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* --------------
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*
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* Copyright (C) 1997-2001 Ken Turkowski. <turk_at_computer.org>
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*
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* Permission is hereby granted, free of charge, to any person obtaining
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* a copy of this software and associated documentation files (the
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* "Software"), to deal in the Software without restriction, including
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* without limitation the rights to use, copy, modify, merge, publish,
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* distribute, sublicense, and/or sell copies of the Software, and to
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* permit persons to whom the Software is furnished to do so, subject to
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* the following conditions:
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*
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* The above copyright notice and this permission notice shall be included
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* in all copies or substantial portions of the Software.
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*
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* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
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* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
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* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
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* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
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* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
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* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
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* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
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*
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* ------------------------------------------------------------------------
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*
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* Solve:
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* coeff[3] * x^3 + coeff[2] * x^2 + coeff[1] * x + coeff[0] = 0
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*
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* returns:
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* 3 - 3 real roots
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* 1 - 1 real root (2 complex conjugate)
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*
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*******************************************************************************/
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/*long
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FindCubicRoots(const FLOAT coeff[4], FLOAT x[3])
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{
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FLOAT a1 = coeff[2] / coeff[3];
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FLOAT a2 = coeff[1] / coeff[3];
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FLOAT a3 = coeff[0] / coeff[3];
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double_t Q = (a1 * a1 - 3 * a2) / 9;
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double_t R = (2 * a1 * a1 * a1 - 9 * a1 * a2 + 27 * a3) / 54;
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double_t Qcubed = Q * Q * Q;
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double_t d = Qcubed - R * R;
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// Three real roots
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if (d >= 0) {
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double_t theta = acos(R / sqrt(Qcubed));
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double_t sqrtQ = sqrt(Q);
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x[0] = -2 * sqrtQ * cos( theta / 3) - a1 / 3;
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x[1] = -2 * sqrtQ * cos((theta + 2 * pi) / 3) - a1 / 3;
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x[2] = -2 * sqrtQ * cos((theta + 4 * pi) / 3) - a1 / 3;
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return (3);
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}
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// One real root
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else {
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double_t e = pow(sqrt(-d) + fabs(R), 1. / 3.);
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if (R > 0)
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e = -e;
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x[0] = (e + Q / e) - a1 / 3.;
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return (1);
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}
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}
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*/
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#endif
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