include/cinder/Path2d.h

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/*
 Copyright (c) 2010, The Barbarian Group
 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.

 THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED
 WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
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 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)
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*/

#pragma once

#include "cinder/Vector.h"
#include "cinder/BSpline.h"
#include "cinder/Rect.h"
#include "cinder/Exception.h"
#include "cinder/MatrixAffine2.h"

#include <vector>

namespace cinder {

class Path2d {
 public:
    Path2d() {}
    explicit Path2d( const BSpline<Vec2f> &spline, float subdivisionStep = 0.01f );

    void    moveTo( const Vec2f &p );
    void    moveTo( float x, float y ) { moveTo( Vec2f( x, y ) ); }
    void    lineTo( const Vec2f &p );
    void    lineTo( float x, float y ) { lineTo( Vec2f( x, y ) ); }
    void    quadTo( const Vec2f &p1, const Vec2f &p2 );
    void    quadTo( float x1, float y1, float x2, float y2 ) { quadTo( Vec2f( x1, y1 ), Vec2f( x2, y2 ) ); }
    void    curveTo( const Vec2f &p1, const Vec2f &p2, const Vec2f &p3 );
    void    curveTo( float x1, float y1, float x2, float y2, float x3, float y3 ) { curveTo( Vec2f( x1, y1 ), Vec2f( x2, y2 ), Vec2f( x3, y3 ) ); }
    void    arc( const Vec2f &center, float radius, float startRadians, float endRadians, bool forward = true );
    void    arc( float centerX, float centerY, float radius, float startRadians, float endRadians, bool forward = true ) { arc( Vec2f( centerX, centerY ), radius, startRadians, endRadians, forward ); }
    void    arcTo( const Vec2f &p, const Vec2f &t, float radius );
    void    arcTo( float x, float y, float tanX, float tanY, float radius) { arcTo( Vec2f( x, y ), Vec2f( tanX, tanY ), radius ); }
    
    void    close() { mSegments.push_back( CLOSE ); }
    bool    isClosed() const { return ( mSegments.size() > 1 ) && mSegments.back() == CLOSE; }
    
    void    reverse();
    
    bool    empty() const { return mPoints.empty(); }
    void    clear() { mSegments.clear(); mPoints.clear(); }
    size_t  getNumSegments() const { return mSegments.size(); }
    size_t  getNumPoints() const { return mPoints.size(); }

    Vec2f   getPosition( float t ) const;
    Vec2f   getSegmentPosition( size_t segment, float t ) const;
    
    std::vector<Vec2f>  subdivide( float approximationScale = 1.0f ) const;
    
    void        scale( const Vec2f &amount, Vec2f scaleCenter = Vec2f::zero() );
    void        transform( const MatrixAffine2f &matrix );
    Path2d      transformCopy( const MatrixAffine2f &matrix ) const;


    const std::vector<Vec2f>&   getPoints() const { return mPoints; }
    std::vector<Vec2f>&         getPoints() { return mPoints; }
    const Vec2f&                getPoint( size_t point ) const { return mPoints[point]; }
    Vec2f&                      getPoint( size_t point ) { return mPoints[point]; }
    const Vec2f&                getCurrentPoint() const { return mPoints.back(); }
    void                        setPoint( size_t index, const Vec2f &p ) { mPoints[index] = p; }

    enum SegmentType { MOVETO, LINETO, QUADTO, CUBICTO, CLOSE };
    static const int sSegmentTypePointCounts[];
    SegmentType     getSegmentType( size_t segment ) const { return mSegments[segment]; }

    const std::vector<SegmentType>& getSegments() const { return mSegments; }
    std::vector<SegmentType>&       getSegments() { return mSegments; }

    void            removeSegment( size_t segment );
    
    Rectf   calcBoundingBox() const;
    Rectf   calcPreciseBoundingBox() const; 

    bool    contains( const Vec2f &pt ) const;

    static int      calcQuadraticBezierMonotoneRegions( const Vec2f p[3], float resultT[2] );
    static Vec2f    calcQuadraticBezierPos( const Vec2f p[3], float t );
    static int      calcCubicBezierMonotoneRegions( const Vec2f p[4], float resultT[4] );
    static Vec2f    calcCubicBezierPos( const Vec2f p[4], float t );

    friend class Shape2d;
    friend std::ostream& operator<<( std::ostream &out, const Path2d &p );
  private:
    void    arcHelper( const Vec2f &center, float radius, float startRadians, float endRadians, bool forward );
    void    arcSegmentAsCubicBezier( const Vec2f &center, float radius, float startRadians, float endRadians );
    void    subdivideQuadratic( float distanceToleranceSqr, const Vec2f &p1, const Vec2f &p2, const Vec2f &p3, int level, std::vector<Vec2f> *result ) const;
    void    subdivideCubic( float distanceToleranceSqr, const Vec2f &p1, const Vec2f &p2, const Vec2f &p3, const Vec2f &p4, int level, std::vector<Vec2f> *result ) const;

    std::vector<Vec2f>          mPoints;
    std::vector<SegmentType>    mSegments;
};

inline std::ostream& operator<<( std::ostream &out, const Path2d &p )
{
    size_t pt = 0;
    for( size_t s = 0; s < p.mSegments.size(); ++s ) {
        if( p.mSegments[s] == Path2d::MOVETO ) {
            out << "M " << p.mPoints[pt].x << " " << p.mPoints[pt].y << " ";
            pt++;
        }
        if( p.mSegments[s] == Path2d::LINETO ) {
            out << "L " << p.mPoints[pt].x << " " << p.mPoints[pt].y << " ";
            pt++;
        }
        else if( p.mSegments[s] == Path2d::QUADTO ) {
            out << "Q " << p.mPoints[pt].x << " " << p.mPoints[pt].y << " " << p.mPoints[pt+1].x << " " << p.mPoints[pt+1].y << " ";
            pt += 2;
        }
        else if( p.mSegments[s] == Path2d::CUBICTO ) {
            out << "C " << p.mPoints[pt].x << " " << p.mPoints[pt].y << " " << p.mPoints[pt+1].x << " " << p.mPoints[pt+1].y << " " << p.mPoints[pt+2].x << " " << p.mPoints[pt+2].y << " ";
            pt += 3;
        }
        else {
            out << "Z ";
        }

    }
    
    return out;
}

class Path2dExc : public Exception {
};

} // namespace cinder