BezierCurve Class Reference

#include <BezierCurve.h>

Public Member Functions
	BezierCurve ()
	BezierCurve (size_t numberOfStepsOnCurve)
std::vector< CLPoint >	curvePts (const std::vector< CLPoint > &pts)

Private Member Functions
C_FLOAT64	bernstein (C_INT32 i, C_INT32 n, C_FLOAT64 t)
CLPoint	bezierPt (C_FLOAT64 t, std::vector< CLPoint > pts)
void	init ()
C_FLOAT64	multiplyFromTo (C_INT32 n1, C_INT32 n2)

Private Attributes
C_FLOAT64	dt
size_t	steps
C_FLOAT64	t

Detailed Description

Definition at line 37 of file BezierCurve.h.

Constructor & Destructor Documentation

BezierCurve::BezierCurve

(

)

Definition at line 32 of file BezierCurve.cpp.

References init().

{
  init();
}

BezierCurve::BezierCurve

(

size_t

numberOfStepsOnCurve

)

Definition at line 37 of file BezierCurve.cpp.

References steps, and t.

{
  steps = numberOfStepsOnCurve;
  t = 1.0 / steps;
}

Member Function Documentation

C_FLOAT64 BezierCurve::bernstein ( C_INT32  i, C_INT32  n, C_FLOAT64  t  )

private

Definition at line 79 of file BezierCurve.cpp.

References C_FLOAT64, and multiplyFromTo().

Referenced by bezierPt(), and curvePts().

{

  // first compute n over i
  C_FLOAT64 top = multiplyFromTo(n - i + 1, n);
  C_FLOAT64 bottom = multiplyFromTo(1, i);

  return (top / bottom * pow(t, (C_FLOAT64)i) * pow(1.0 - t, (C_FLOAT64)n - i));
}

CLPoint BezierCurve::bezierPt ( C_FLOAT64  t, std::vector< CLPoint >  pts  )

private

Definition at line 89 of file BezierCurve.cpp.

References bernstein(), C_FLOAT64, and C_INT32.

{
  C_INT32 i;
  C_FLOAT64 x = 0.0;
  C_FLOAT64 y = 0.0;

  C_INT32 n = (C_INT32) pts.size() - 1;

  for (i = 0; i <= n; i++)
    {
      x += bernstein(i, n, t) * pts[i].getX();
      y += bernstein(i, n, t) * pts[i].getY();
    }

  return CLPoint(x, y);
}

std::vector< CLPoint > BezierCurve::curvePts

(

const std::vector< CLPoint > &

pts

)

Definition at line 49 of file BezierCurve.cpp.

References bernstein(), C_FLOAT64, C_INT32, dt, and t.

Referenced by CGraphCurve::invertOrderOfPoints().

{
  C_FLOAT64 x;
  C_FLOAT64 y;
  std::vector<CLPoint>points;
  points = std::vector<CLPoint>();

  C_FLOAT64 t = 0.0;

  C_INT32 i;
  C_INT32 n = (C_INT32) pts.size() - 1;

  while (t <= 1.0000001)
    {
      x = 0.0;
      y = 0.0;

      for (i = 0; i <= n; i++)
        {
          x += bernstein(i, n, t) * pts[i].getX();
          y += bernstein(i, n, t) * pts[i].getY();
        }

      points.push_back(CLPoint(x, y));
      t += dt;
    }

  return points;
}

void BezierCurve::init ( )

private

Definition at line 43 of file BezierCurve.cpp.

References dt, and steps.

Referenced by BezierCurve().

{
  steps = 100;
  dt = 0.01;
}

C_FLOAT64 BezierCurve::multiplyFromTo ( C_INT32  n1, C_INT32  n2  )

private

Definition at line 108 of file BezierCurve.cpp.

References C_FLOAT64, and C_INT32.

Referenced by bernstein().

{
  C_INT32 i;
  C_FLOAT64 prod = 1;

  if (n2 >= n1)
    {
      for (i = n1; i <= n2; i++)
        prod *= (C_FLOAT64)i;
    }

  return prod;
}

Member Data Documentation

C_FLOAT64 BezierCurve::dt

private

Definition at line 47 of file BezierCurve.h.

Referenced by curvePts(), and init().

size_t BezierCurve::steps

private

Definition at line 46 of file BezierCurve.h.

Referenced by BezierCurve(), and init().

C_FLOAT64 BezierCurve::t

private

Definition at line 45 of file BezierCurve.h.

Referenced by BezierCurve(), and curvePts().

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The documentation for this class was generated from the following files:

• BezierCurve.h
• BezierCurve.cpp