fit.h

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/*
 * fit.h
 *
 * Copyright (C) 2007   Thomas A. Vaughan
 * All rights reserved.
 *
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *     * Redistributions of source code must retain the above copyright
 *       notice, this list of conditions and the following disclaimer.
 *     * Redistributions in binary form must reproduce the above copyright
 *       notice, this list of conditions and the following disclaimer in the
 *       documentation and/or other materials provided with the distribution.
 *     * Neither the name of the <organization> nor the
 *       names of its contributors may be used to endorse or promote products
 *       derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THOMAS A. VAUGHAN ''AS IS'' AND ANY
 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL THOMAS A. VAUGHAN BE LIABLE FOR ANY
 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 *
 * Functions to fit beziers to a series of points.
 */

#ifndef WAVEPACKET_BEZIER_FIT_H__
#define WAVEPACKET_BEZIER_FIT_H__

// includes --------------------------------------------------------------------
#include "common/common.h"

#include "bezier/bezier.h"
#include "bezier/quad.h"


/// \ingroup bezier
/*@{*/


namespace bezier {


////////////////////////////////////////////////////////////////////////////////
//
//      Quadratic curve fitting
//
////////////////////////////////////////////////////////////////////////////////

typedef std::vector<quad_bezier_t> quad_path_t;

/// given a set of points, return the best fit path of quadratic beziers
void getQuadPathFromRawPoints(IN const point_t * p,
                                IN int nPoints,
                                IN float ds,
                                OUT quad_path_t& path);



////////////////////////////////////////////////////////////////////////////////
//
//      Cubic curve fitting.
//
////////////////////////////////////////////////////////////////////////////////

typedef std::vector<curve_t> path_t;

typedef path_t cubic_path_t;            // I want to deprecate path_t

void getCubicPathFromRawPoints(IN const point_t * p,
                                IN int nPoints,
                                IN float ds,
                                OUT cubic_path_t& path);


float getCoefficient(IN const float * x, IN int nPoints, IN int degree) throw();
void removeCoefficient(IO float * x, IN int nPoints,
                                IN float coeff, IN int degree) throw();

struct fit_t {
        fit_t(void) throw() { this->clear(); }
        void clear(void) throw() {
                        q0 = a = b = c = 0.0;
                }

        void dump(const char * title) const throw() {
                        DPRINTF("  %s  q0=%5.2f  a=%5.2f  b=%5.2f  c=%5.2f",
                            title, q0, a, b, c);
                }

        float getq(IN float t) const throw() {
                        float q = q0;
                        q += c * t;
                        q += b * t * t;
                        q += a * t * t * t;
                        return q;
                }

        // data fields
        float           q0;
        float           a;
        float           b;
        float           c;
};


void fitPoints(IN const float * x, IN int nPoints,
                                IN float slope,
                                OUT fit_t& fit) throw();

int getCuspIndices(IN const point_t * p, IN int nPoints,
                                OUT int ** cusps);

float getFitQuality(IN const point_t * p, IN int nPoints,
                                IN const curve_t& curve) throw();

void fitPath(IN const point_t * p, IN int nPoints,
                                IN float tolerance,
                                OUT path_t& path);

void respacePath(IN const point_t * p, IN int nPoints,
                                IN float ds,            // path step increment
                                OUT point_t ** out_p,   // points to static memory!
                                OUT int& newPoints);

};      // bezier namespace

#endif  // WAVEPACKET_BEZIER_FIT_H__