SplineAssistant.cc File Reference

#include "SplineAssistant.h"
#include <klocalizedstring.h>
#include <QPainter>
#include <QPainterPath>
#include <QLinearGradient>
#include <QTransform>
#include <kis_canvas2.h>
#include <kis_coordinates_converter.h>
#include "kis_debug.h"
#include "KisBezierUtils.h"
#include <KoColorDisplayRendererInterface.h>
#include <math.h>
#include <limits>
#include <algorithm>

Go to the source code of this file.

Classes
struct	GoldenSearchParams
struct	GoldenSearchParams::GoldenSearchPoint
struct	SplineAssistant::Private

Functions
QPointF	B (qreal t, const QPointF &P0, const QPointF &P1, const QPointF &P2, const QPointF &P3)
qreal	D (qreal t, const QPointF &P0, const QPointF &P1, const QPointF &P2, const QPointF &P3, const QPointF &p)
qreal	goldenSearch (const QPointF &pt, const QList< KisPaintingAssistantHandleSP > handles, qreal low, qreal high, qreal tolerance, uint max_iter)

Function Documentation

B()

QPointF B ( qreal t, const QPointF & P0, const QPointF & P1, const QPointF & P2, const QPointF & P3 )

inline

Definition at line 94 of file SplineAssistant.cc.

{
    const qreal tp = 1 - t;
    const qreal tp2 = tp * tp;
    const qreal t2 = t * t;
 
    return  (    tp2 * tp) * P0 +
            (3 * tp2 * t ) * P1 +
            (3 * tp  * t2) * P2 +
            (    t   * t2) * P3;
}

D()

qreal D ( qreal t, const QPointF & P0, const QPointF & P1, const QPointF & P2, const QPointF & P3, const QPointF & p )

inline

Definition at line 106 of file SplineAssistant.cc.

{
    const qreal
            tp =  1 - t,
            tp2 = tp * tp,
            t2 =  t * t,
            a =   tp2 * tp,
            b =   3 * tp2 * t,
            c =   3 * tp  * t2,
            d =   t   * t2,
            x_dist = a*P0.x() + b*P1.x() + c*P2.x() + d*P3.x() - p.x(),
            y_dist = a*P0.y() + b*P1.y() + c*P2.y() + d*P3.y() - p.y();
 
    return x_dist * x_dist + y_dist * y_dist;
}

References p.

goldenSearch()

qreal goldenSearch ( const QPointF & pt, const QList< KisPaintingAssistantHandleSP > handles, qreal low, qreal high, qreal tolerance, uint max_iter )

inline

Definition at line 123 of file SplineAssistant.cc.

{
    GoldenSearchParams ovalues = GoldenSearchParams(low,high);
    QVector<GoldenSearchParams::GoldenSearchPoint> p = ovalues.samples;
    qreal u = ovalues.ubound;
    qreal l = ovalues.lbound;
 
    const qreal ratio = 1 - 2/(1 + sqrt(5));
    p[0].x = 0;
    p[1].x = ratio;
    p[2].x = 1 - p[1].x;
    p[3].x = 1;
 
    p[1].inv_norm(l,u);
    p[2].inv_norm(l,u);
 
    p[1].fval = D(p[1].xnorm, *handles[0], *handles[2], *handles[3], *handles[1], pt);
    p[2].fval = D(p[2].xnorm, *handles[0], *handles[2], *handles[3], *handles[1], pt);
 
    GoldenSearchParams::GoldenSearchPoint xtemp = GoldenSearchParams::GoldenSearchPoint(0);
 
    uint i = 0; // used to force early exit
    while ( qAbs(p[2].xnorm - p[1].xnorm) > tolerance && i < max_iter) {
 
        if (p[1].fval < p[2].fval) {
            xtemp = p[1];
            p[3] = p[2];
            p[1].x = p[0].x + (p[2].x - p[1].x);
            p[2] = xtemp;
 
            p[1].inv_norm(l,u);
            p[1].fval = D(p[1].xnorm, *handles[0], *handles[2], *handles[3], *handles[1], pt);
 
        } else {
            xtemp = p[2];
            p[0] = p[1];
            p[2].x = p[1].x + (p[3].x - p[2].x);
            p[1] = xtemp;
 
            p[2].inv_norm(l,u);
            p[2].fval = D(p[2].xnorm, *handles[0], *handles[2], *handles[3], *handles[1], pt);
 
        }
        i++;
    }
    return (p[2].xnorm + p[1].xnorm) / 2;
}

References D(), GoldenSearchParams::GoldenSearchPoint::inv_norm(), GoldenSearchParams::lbound, p, GoldenSearchParams::samples, u, GoldenSearchParams::ubound, and GoldenSearchParams::GoldenSearchPoint::x.