vpImageDraw.cpp

/****************************************************************************
 *
 * ViSP, open source Visual Servoing Platform software.
 * Copyright (C) 2005 - 2019 by Inria. All rights reserved.
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 * Description:
 * Drawing functions.
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// Contains code from:
/*
 * Simd Library (http://ermig1979.github.io/Simd).
 *
 * Copyright (c) 2011-2017 Yermalayeu Ihar.
 *
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#include <visp3/core/vpImageDraw.h>
#include <visp3/core/vpMeterPixelConversion.h>
#include <visp3/core/vpPoint.h>
 
namespace
{
template <class Type>
void DrawLine(vpImage<Type> &canvas, int x1, int y1, int x2, int y2, const Type &color, unsigned int width = 1)
{
  const int w = static_cast<int>(canvas.getWidth()) - 1;
  const int h = static_cast<int>(canvas.getHeight()) - 1;
 
  if (x1 < 0 || y1 < 0 || (x1 - w) > 0 || (y1 - h) > 0 || x2 < 0 || y2 < 0 || (x2 - w) > 0 || (y2 - h) > 0) {
    if ((x1 < 0 && x2 < 0) || (y1 < 0 && y2 < 0) || ((x1 - w) > 0 && (x2 - w) > 0) || ((y1 - h) > 0 && (y2 - h) > 0)) {
      return;
    }
 
    if (y1 == y2) {
      x1 = std::min<int>(std::max<int>(x1, 0), w);
      x2 = std::min<int>(std::max<int>(x2, 0), w);
    } else if (x1 == x2) {
      y1 = std::min<int>(std::max<int>(y1, 0), h);
      y2 = std::min<int>(std::max<int>(y2, 0), h);
    } else {
      int x0 = (x1 * y2 - y1 * x2) / (y2 - y1);
      int y0 = (y1 * x2 - x1 * y2) / (x2 - x1);
      int xh = (x1 * y2 - y1 * x2 + h * (x2 - x1)) / (y2 - y1);
      int yw = (y1 * x2 - x1 * y2 + w * (y2 - y1)) / (x2 - x1);
 
      if (x1 < 0) {
        x1 = 0;
        y1 = y0;
      }
      if (x2 < 0) {
        x2 = 0;
        y2 = y0;
      }
      if (x1 > w) {
        x1 = w;
        y1 = yw;
      }
      if (x2 > w) {
        x2 = w;
        y2 = yw;
      }
      if ((y1 < 0 && y2 < 0) || (y1 > h && y2 > h)) {
        return;
      }
 
      if (y1 < 0) {
        x1 = x0;
        y1 = 0;
      }
      if (y2 < 0) {
        x2 = x0;
        y2 = 0;
      }
 
      if (y1 > h) {
        x1 = xh;
        y1 = h;
      }
      if (y2 > h) {
        x2 = xh;
        y2 = h;
      }
    }
  }
 
  const bool inverse = ((std::abs(y2 - y1) - std::abs(x2 - x1)) > 0);
  if (inverse) {
    std::swap(x1, y1);
    std::swap(x2, y2);
  }
 
  if (x1 > x2) {
    std::swap(x1, x2);
    std::swap(y1, y2);
  }
 
  const double dx = x2 - x1;
  const double dy = static_cast<double>(std::abs(y2 - y1));
 
  double error = dx / 2.0f;
  const int ystep = (y1 < y2) ? 1 : -1;
  int y0 = y1 - static_cast<int>(width) / 2;
 
  for (int x = x1; x <= x2; x++) {
    for (int i = 0; i < static_cast<int>(width); i++) {
      int y = y0 + i;
      if (y >= 0) {
        if (inverse) {
          if (y < w) {
            canvas[x][y] = color;
          }
        } else {
          if (y < h) {
            canvas[y][x] = color;
          }
        }
      }
    }
 
    error -= dy;
    if (error < 0) {
      y0 += ystep;
      error += dx;
    }
  }
}
 
template <class Type>
void DrawCircle(vpImage<Type> &canvas, const vpImagePoint &center, int radius, const Type &color,
                unsigned int width = 1)
{
  const size_t n = 8 * std::max(static_cast<size_t>(1), static_cast<size_t>(::pow(radius, 0.5)));
  double px = 0, py = 0, da = 2 * M_PI / n;
  for (size_t i = 0; i <= n; i++) {
    double a = i * da;
    double cx = radius * ::cos(a) + center.get_u();
    double cy = radius * ::sin(a) + center.get_v();
    if (i > 0) {
      DrawLine(canvas, static_cast<int>(cx), static_cast<int>(cy), static_cast<int>(px), static_cast<int>(py), color,
               width);
    }
    px = cx;
    py = cy;
  }
}
 
template <class Type> void DrawFilledRectangle(vpImage<Type> &canvas, vpRect rect, const Type &color)
{
  rect &= vpRect(0, 0, canvas.getWidth(), canvas.getHeight());
  for (int row = static_cast<int>(rect.getTop()); row < static_cast<int>(rect.getBottom()); row++) {
    Type *dst = canvas[row];
    for (int col = static_cast<int>(rect.getLeft()); col < static_cast<int>(rect.getRight()); col++) {
      dst[col] = color;
    }
  }
}
 
template <class Type>
void DrawPolygon(vpImage<Type> &canvas, const std::vector<vpImagePoint> &polygon, const Type &color,
                 unsigned int width = 1, bool closed = true)
{
  if (closed) {
    for (size_t i = 0; i < polygon.size(); i++) {
      const vpImagePoint &p1 = (i ? polygon[i - 1] : polygon.back()), p2 = polygon[i];
      DrawLine(canvas, static_cast<int>(p1.get_u()), static_cast<int>(p1.get_v()), static_cast<int>(p2.get_u()),
               static_cast<int>(p2.get_v()), color, width);
    }
  } else {
    for (size_t i = 1; i < polygon.size(); i++) {
      DrawLine(canvas, static_cast<int>(polygon[i - 1].get_u()), static_cast<int>(polygon[i - 1].get_v()),
               static_cast<int>(polygon[i].get_u()), static_cast<int>(polygon[i].get_v()), color, width);
    }
  }
}
 
template <class Type>
void DrawRectangle(vpImage<Type> &canvas, const vpRect &rect, const Type &color, unsigned int width = 1)
{
  DrawLine(canvas, static_cast<int>(rect.getLeft()), static_cast<int>(rect.getTop()), static_cast<int>(rect.getRight()),
           static_cast<int>(rect.getTop()), color, width);
  DrawLine(canvas, static_cast<int>(rect.getRight()), static_cast<int>(rect.getTop()),
           static_cast<int>(rect.getRight()), static_cast<int>(rect.getBottom()), color, width);
  DrawLine(canvas, static_cast<int>(rect.getRight()), static_cast<int>(rect.getBottom()),
           static_cast<int>(rect.getLeft()), static_cast<int>(rect.getBottom()), color, width);
  DrawLine(canvas, static_cast<int>(rect.getLeft()), static_cast<int>(rect.getBottom()),
           static_cast<int>(rect.getLeft()), static_cast<int>(rect.getTop()), color, width);
}
} // namespace
 
void vpImageDraw::drawArrow(vpImage<unsigned char> &I, const vpImagePoint &ip1, const vpImagePoint &ip2,
                            unsigned char color, unsigned int w, unsigned int h, unsigned int thickness)
{
  double a = ip2.get_i() - ip1.get_i();
  double b = ip2.get_j() - ip1.get_j();
  double lg = sqrt(vpMath::sqr(a) + vpMath::sqr(b));
 
  if ((std::fabs(a) <= std::numeric_limits<double>::epsilon()) &&
      (std::fabs(b) <= std::numeric_limits<double>::epsilon())) {
    // DisplayCrossLarge(i1,j1,3,col) ;
  } else {
    a /= lg;
    b /= lg;
 
    vpImagePoint ip3;
    ip3.set_i(ip2.get_i() - w * a);
    ip3.set_j(ip2.get_j() - w * b);
 
    vpImagePoint ip4;
    ip4.set_i(ip3.get_i() - b * h);
    ip4.set_j(ip3.get_j() + a * h);
 
    if (lg > 2 * vpImagePoint::distance(ip2, ip4)) {
      drawLine(I, ip2, ip4, color, thickness);
    }
 
    ip4.set_i(ip3.get_i() + b * h);
    ip4.set_j(ip3.get_j() - a * h);
 
    if (lg > 2 * vpImagePoint::distance(ip2, ip4)) {
      drawLine(I, ip2, ip4, color, thickness);
    }
 
    drawLine(I, ip1, ip2, color, thickness);
  }
}
 
void vpImageDraw::drawArrow(vpImage<vpRGBa> &I, const vpImagePoint &ip1, const vpImagePoint &ip2, const vpColor &color,
                            unsigned int w, unsigned int h, unsigned int thickness)
{
  double a = ip2.get_i() - ip1.get_i();
  double b = ip2.get_j() - ip1.get_j();
  double lg = sqrt(vpMath::sqr(a) + vpMath::sqr(b));
 
  if ((std::fabs(a) <= std::numeric_limits<double>::epsilon()) &&
      (std::fabs(b) <= std::numeric_limits<double>::epsilon())) {
    // DisplayCrossLarge(i1,j1,3,col) ;
  } else {
    a /= lg;
    b /= lg;
 
    vpImagePoint ip3;
    ip3.set_i(ip2.get_i() - w * a);
    ip3.set_j(ip2.get_j() - w * b);
 
    vpImagePoint ip4;
    ip4.set_i(ip3.get_i() - b * h);
    ip4.set_j(ip3.get_j() + a * h);
 
    if (lg > 2 * vpImagePoint::distance(ip2, ip4)) {
      drawLine(I, ip2, ip4, color, thickness);
    }
 
    ip4.set_i(ip3.get_i() + b * h);
    ip4.set_j(ip3.get_j() - a * h);
 
    if (lg > 2 * vpImagePoint::distance(ip2, ip4)) {
      drawLine(I, ip2, ip4, color, thickness);
    }
 
    drawLine(I, ip1, ip2, color, thickness);
  }
}
 
void vpImageDraw::drawCircle(vpImage<unsigned char> &I, const vpImagePoint &center, unsigned int radius,
                             unsigned char color, unsigned int thickness)
{
  DrawCircle(I, center, static_cast<int>(radius), color, thickness);
}
 
void vpImageDraw::drawCircle(vpImage<vpRGBa> &I, const vpImagePoint &center, unsigned int radius, const vpColor &color,
                             unsigned int thickness)
{
  DrawCircle(I, center, static_cast<int>(radius), vpRGBa(color.R, color.G, color.B), thickness);
}
 
void vpImageDraw::drawCross(vpImage<unsigned char> &I, const vpImagePoint &ip, unsigned int size, unsigned char color,
                            unsigned int thickness)
{
  vpImagePoint top, bottom, left, right;
  top.set_i(ip.get_i() - size / 2);
  top.set_j(ip.get_j());
  bottom.set_i(ip.get_i() + size / 2);
  bottom.set_j(ip.get_j());
  left.set_i(ip.get_i());
  left.set_j(ip.get_j() - size / 2);
  right.set_i(ip.get_i());
  right.set_j(ip.get_j() + size / 2);
  drawLine(I, top, bottom, color, thickness);
  drawLine(I, left, right, color, thickness);
}
 
void vpImageDraw::drawCross(vpImage<vpRGBa> &I, const vpImagePoint &ip, unsigned int size, const vpColor &color,
                            unsigned int thickness)
{
  vpImagePoint top, bottom, left, right;
  top.set_i(ip.get_i() - size / 2);
  top.set_j(ip.get_j());
  bottom.set_i(ip.get_i() + size / 2);
  bottom.set_j(ip.get_j());
  left.set_i(ip.get_i());
  left.set_j(ip.get_j() - size / 2);
  right.set_i(ip.get_i());
  right.set_j(ip.get_j() + size / 2);
  drawLine(I, top, bottom, color, thickness);
  drawLine(I, left, right, color, thickness);
}
 
void vpImageDraw::drawDottedLine(vpImage<unsigned char> &I, const vpImagePoint &ip1, const vpImagePoint &ip2,
                                 unsigned char color, unsigned int thickness)
{
  vpImagePoint ip1_ = ip1;
  vpImagePoint ip2_ = ip2;
 
  double size = 10;
  double length = sqrt(vpMath::sqr(ip2_.get_i() - ip1_.get_i()) + vpMath::sqr(ip2_.get_j() - ip1_.get_j()));
  bool vertical_line = static_cast<int>(ip2_.get_j()) == static_cast<int>(ip1_.get_j());
  if (vertical_line) {
    if (ip2_.get_i() < ip1_.get_i()) {
      std::swap(ip1_, ip2_);
    }
  } else if (ip2_.get_j() < ip1_.get_j()) {
    std::swap(ip1_, ip2_);
  }
 
  double diff_j = vertical_line ? 1 : ip2_.get_j() - ip1_.get_j();
  double deltaj = size / length * diff_j;
  double deltai = size / length * (ip2_.get_i() - ip1_.get_i());
  double slope = (ip2_.get_i() - ip1_.get_i()) / diff_j;
  double orig = ip1_.get_i() - slope * ip1_.get_j();
 
  if (vertical_line) {
    for (unsigned int i = static_cast<unsigned int>(ip1_.get_i()); i < ip2_.get_i();
         i += static_cast<unsigned int>(2 * deltai)) {
      double j = ip1_.get_j();
      drawLine(I, vpImagePoint(i, j), vpImagePoint(i + deltai, j), color, thickness);
    }
  } else {
    for (unsigned int j = static_cast<unsigned int>(ip1_.get_j()); j < ip2_.get_j();
         j += static_cast<unsigned int>(2 * deltaj)) {
      double i = slope * j + orig;
      drawLine(I, vpImagePoint(i, j), vpImagePoint(i + deltai, j + deltaj), color, thickness);
    }
  }
}
 
void vpImageDraw::drawDottedLine(vpImage<vpRGBa> &I, const vpImagePoint &ip1, const vpImagePoint &ip2,
                                 const vpColor &color, unsigned int thickness)
{
  vpImagePoint ip1_ = ip1;
  vpImagePoint ip2_ = ip2;
 
  double size = 10;
  double length = sqrt(vpMath::sqr(ip2_.get_i() - ip1_.get_i()) + vpMath::sqr(ip2_.get_j() - ip1_.get_j()));
  bool vertical_line = static_cast<int>(ip2_.get_j()) == static_cast<int>(ip1_.get_j());
  if (vertical_line) {
    if (ip2_.get_i() < ip1_.get_i()) {
      std::swap(ip1_, ip2_);
    }
  } else if (ip2_.get_j() < ip1_.get_j()) {
    std::swap(ip1_, ip2_);
  }
 
  double diff_j = vertical_line ? 1 : ip2_.get_j() - ip1_.get_j();
  double deltaj = size / length * diff_j;
  double deltai = size / length * (ip2_.get_i() - ip1_.get_i());
  double slope = (ip2_.get_i() - ip1_.get_i()) / diff_j;
  double orig = ip1_.get_i() - slope * ip1_.get_j();
 
  if (vertical_line) {
    for (unsigned int i = static_cast<unsigned int>(ip1_.get_i()); i < ip2_.get_i();
         i += static_cast<unsigned int>(2 * deltai)) {
      double j = ip1_.get_j();
      drawLine(I, vpImagePoint(i, j), vpImagePoint(i + deltai, j), color, thickness);
    }
  } else {
    for (unsigned int j = static_cast<unsigned int>(ip1_.get_j()); j < ip2_.get_j();
         j += static_cast<unsigned int>(2 * deltaj)) {
      double i = slope * j + orig;
      drawLine(I, vpImagePoint(i, j), vpImagePoint(i + deltai, j + deltaj), color, thickness);
    }
  }
}
 
void vpImageDraw::drawEllipse(vpImage<unsigned char> &I, const vpImagePoint &center, double coef1, double coef2,
                              double coef3, bool use_normalized_centered_moments, unsigned char color,
                              double smallalpha, double highalpha, unsigned int thickness)
{
  double a = 0., b = 0., e = 0.;
 
  if (use_normalized_centered_moments) {
    // Chaumette, Image Moments: A General and Useful Set of Features for Visual Servoing, TRO 2004, eq 24
    // Similar code as in function vpMeEllipse::computeAbeFromNij() in vpMeEllipse.cpp
    double n20_p = coef1;
    double n11_p = coef2;
    double n02_p = coef3;
    double num = n20_p - n02_p;
    double d = num * num + 4.0 * n11_p * n11_p; // always >= 0
 
    if (d <= std::numeric_limits<double>::epsilon()) { // circle
      e = 0.0;                                         // case n20 = n02 and n11 = 0 : circle, e undefined
      a = b = 2.0 * sqrt(n20_p);
    } else {                             // real ellipse
      e = atan2(2.0 * n11_p, num) / 2.0; // e in [-Pi/2 ; Pi/2]
      d = sqrt(d);                       // d in sqrt always >= 0
      num = n20_p + n02_p;
      a = sqrt(2.0 * (num + d)); // term in sqrt always > 0
      b = sqrt(2.0 * (num - d)); // term in sqrt always > 0
    }
  } else {
    a = coef1;
    b = coef2;
    e = coef3;
  }
 
  // For all what follows similar code as in function vpMeEllipse::display() in vpMeEllipse.cpp
 
  // Approximation of the circumference of an ellipse:
  // [Ramanujan, S., "Modular Equations and Approximations to ,"
  // Quart. J. Pure. Appl. Math., vol. 45 (1913-1914), pp. 350-372]
  double angle = highalpha - smallalpha;
 
  double t = (a - b) / (a + b);
  t *= t; // t^2
  double circumference = (angle / 2.0) * (a + b) * (1.0 + 3.0 * t / (10.0 + sqrt(4.0 - 3.0 * t)));
  unsigned int nbpoints = (unsigned int)(floor(circumference / 20));
  if (nbpoints < 10) {
    nbpoints = 10;
  }
  double incr = angle / nbpoints; // angle increment
 
  double u0 = center.get_u();
  double v0 = center.get_v();
  double cose = cos(e);
  double sine = sin(e);
 
  double u = a * cos(smallalpha); // equation of an ellipse
  double v = b * sin(smallalpha); // equation of an ellipse
  angle = smallalpha;
  // (i1,j1) are the coordinates on the origin centered ellipse ;
  // a rotation by "e" and a translation by (xci,jc) are done
  // to get the coordinates of the point on the shifted ellipse
  vpImagePoint iP11;
  iP11.set_uv(u0 + cose * u - sine * v, v0 + sine * u + cose * v);
 
  // display the arc of the ellipse by successive small segments
  for (unsigned int i = 0; i < nbpoints; i++) {
    angle += incr;
    // Two concentric circles method used
    u = a * cos(angle);
    v = b * sin(angle);
    // to get the coordinates of the point on the shifted ellipse
    vpImagePoint iP22;
    iP22.set_uv(u0 + cose * u - sine * v, v0 + sine * u + cose * v);
 
    drawLine(I, iP11, iP22, color, thickness);
 
    iP11 = iP22;
  }
}
 
void vpImageDraw::drawEllipse(vpImage<vpRGBa> &I, const vpImagePoint &center, double coef1, double coef2, double coef3,
                              bool use_normalized_centered_moments, const vpColor &color, double smallalpha,
                              double highalpha, unsigned int thickness)
{
  double a = 0., b = 0., e = 0.;
 
  if (use_normalized_centered_moments) {
    // Chaumette, Image Moments: A General and Useful Set of Features for Visual Servoing, TRO 2004, eq 24
    // Similar code as in function vpMeEllipse::computeAbeFromNij() in vpMeEllipse.cpp
    double n20_p = coef1;
    double n11_p = coef2;
    double n02_p = coef3;
    double num = n20_p - n02_p;
    double d = num * num + 4.0 * n11_p * n11_p; // always >= 0
 
    if (d <= std::numeric_limits<double>::epsilon()) { // circle
      e = 0.0;                                         // case n20 = n02 and n11 = 0 : circle, e undefined
      a = b = 2.0 * sqrt(n20_p);
    } else {                             // real ellipse
      e = atan2(2.0 * n11_p, num) / 2.0; // e in [-Pi/2 ; Pi/2]
      d = sqrt(d);                       // d in sqrt always >= 0
      num = n20_p + n02_p;
      a = sqrt(2.0 * (num + d)); // term in sqrt always > 0
      b = sqrt(2.0 * (num - d)); // term in sqrt always > 0
    }
  } else {
    a = coef1;
    b = coef2;
    e = coef3;
  }
 
  // For all what follows similar code as in function vpMeEllipse::display() in vpMeEllipse.cpp
 
  // Approximation of the circumference of an ellipse:
  // [Ramanujan, S., "Modular Equations and Approximations to ,"
  // Quart. J. Pure. Appl. Math., vol. 45 (1913-1914), pp. 350-372]
  double angle = highalpha - smallalpha;
 
  double t = (a - b) / (a + b);
  t *= t; // t^2
  double circumference = (angle / 2.0) * (a + b) * (1.0 + 3.0 * t / (10.0 + sqrt(4.0 - 3.0 * t)));
  unsigned int nbpoints = (unsigned int)(floor(circumference / 20));
  if (nbpoints < 10) {
    nbpoints = 10;
  }
  double incr = angle / nbpoints; // angle increment
 
  double u0 = center.get_u();
  double v0 = center.get_v();
  double cose = cos(e);
  double sine = sin(e);
 
  double u = a * cos(smallalpha); // equation of an ellipse
  double v = b * sin(smallalpha); // equation of an ellipse
  angle = smallalpha;
  // (i1,j1) are the coordinates on the origin centered ellipse ;
  // a rotation by "e" and a translation by (xci,jc) are done
  // to get the coordinates of the point on the shifted ellipse
  vpImagePoint iP11;
  iP11.set_uv(u0 + cose * u - sine * v, v0 + sine * u + cose * v);
 
  // display the arc of the ellipse by successive small segments
  for (unsigned int i = 0; i < nbpoints; i++) {
    angle += incr;
    // Two concentric circles method used
    u = a * cos(angle);
    v = b * sin(angle);
    // to get the coordinates of the point on the shifted ellipse
    vpImagePoint iP22;
    iP22.set_uv(u0 + cose * u - sine * v, v0 + sine * u + cose * v);
 
    drawLine(I, iP11, iP22, color, thickness);
 
    iP11 = iP22;
  }
}
 
void vpImageDraw::drawFrame(vpImage<unsigned char> &I, const vpHomogeneousMatrix &cMo, const vpCameraParameters &cam,
                            double size, unsigned char color, unsigned int thickness, const vpImagePoint &offset)
{
  vpPoint o(0.0, 0.0, 0.0);
  vpPoint x(size, 0.0, 0.0);
  vpPoint y(0.0, size, 0.0);
  vpPoint z(0.0, 0.0, size);
 
  o.track(cMo);
  x.track(cMo);
  y.track(cMo);
  z.track(cMo);
 
  vpImagePoint ipo, ip1;
 
  vpMeterPixelConversion::convertPoint(cam, o.p[0], o.p[1], ipo);
 
  vpMeterPixelConversion::convertPoint(cam, x.p[0], x.p[1], ip1);
  drawArrow(I, ipo + offset, ip1 + offset, color, 4 * thickness, 2 * thickness, thickness);
 
  vpMeterPixelConversion::convertPoint(cam, y.p[0], y.p[1], ip1);
  drawArrow(I, ipo + offset, ip1 + offset, color, 4 * thickness, 2 * thickness, thickness);
 
  vpMeterPixelConversion::convertPoint(cam, z.p[0], z.p[1], ip1);
  drawArrow(I, ipo + offset, ip1 + offset, color, 4 * thickness, 2 * thickness, thickness);
}
 
void vpImageDraw::drawFrame(vpImage<vpRGBa> &I, const vpHomogeneousMatrix &cMo, const vpCameraParameters &cam,
                            double size, const vpColor &color, unsigned int thickness, const vpImagePoint &offset)
{
  vpPoint o(0.0, 0.0, 0.0);
  vpPoint x(size, 0.0, 0.0);
  vpPoint y(0.0, size, 0.0);
  vpPoint z(0.0, 0.0, size);
 
  o.track(cMo);
  x.track(cMo);
  y.track(cMo);
  z.track(cMo);
 
  vpImagePoint ipo, ip1;
 
  if (color == vpColor::none) {
    vpMeterPixelConversion::convertPoint(cam, o.p[0], o.p[1], ipo);
 
    vpMeterPixelConversion::convertPoint(cam, x.p[0], x.p[1], ip1);
    drawArrow(I, ipo + offset, ip1 + offset, vpColor::red, 4 * thickness, 2 * thickness, thickness);
 
    vpMeterPixelConversion::convertPoint(cam, y.p[0], y.p[1], ip1);
    drawArrow(I, ipo + offset, ip1 + offset, vpColor::green, 4 * thickness, 2 * thickness, thickness);
 
    vpMeterPixelConversion::convertPoint(cam, z.p[0], z.p[1], ip1);
    drawArrow(I, ipo + offset, ip1 + offset, vpColor::blue, 4 * thickness, 2 * thickness, thickness);
  } else {
    vpMeterPixelConversion::convertPoint(cam, o.p[0], o.p[1], ipo);
 
    vpMeterPixelConversion::convertPoint(cam, x.p[0], x.p[1], ip1);
    drawArrow(I, ipo + offset, ip1 + offset, color, 4 * thickness, 2 * thickness, thickness);
 
    vpMeterPixelConversion::convertPoint(cam, y.p[0], y.p[1], ip1);
    drawArrow(I, ipo + offset, ip1 + offset, color, 4 * thickness, 2 * thickness, thickness);
 
    vpMeterPixelConversion::convertPoint(cam, z.p[0], z.p[1], ip1);
    drawArrow(I, ipo + offset, ip1 + offset, color, 4 * thickness, 2 * thickness, thickness);
  }
}
 
void vpImageDraw::drawLine(vpImage<unsigned char> &I, const vpImagePoint &ip1, const vpImagePoint &ip2,
                           unsigned char color, unsigned int thickness)
{
  DrawLine(I, static_cast<int>(ip1.get_u()), static_cast<int>(ip1.get_v()), static_cast<int>(ip2.get_u()),
           static_cast<int>(ip2.get_v()), color, thickness);
}
 
void vpImageDraw::drawLine(vpImage<vpRGBa> &I, const vpImagePoint &ip1, const vpImagePoint &ip2, const vpColor &color,
                           unsigned int thickness)
{
  DrawLine(I, static_cast<int>(ip1.get_u()), static_cast<int>(ip1.get_v()), static_cast<int>(ip2.get_u()),
           static_cast<int>(ip2.get_v()), vpRGBa(color.R, color.G, color.B), thickness);
}
 
void vpImageDraw::drawPoint(vpImage<unsigned char> &I, const vpImagePoint &ip, unsigned char color,
                            unsigned int thickness)
{
  drawRectangle(I, vpRect(ip, thickness, thickness), color, true);
}
 
void vpImageDraw::drawPoint(vpImage<vpRGBa> &I, const vpImagePoint &ip, const vpColor &color, unsigned int thickness)
{
  drawRectangle(I, vpRect(ip, thickness, thickness), color, true);
}
 
void vpImageDraw::drawPolygon(vpImage<unsigned char> &I, const std::vector<vpImagePoint> &vip, unsigned char color,
                              unsigned int thickness, bool closed)
{
  DrawPolygon(I, vip, color, thickness, closed);
}
 
void vpImageDraw::drawPolygon(vpImage<vpRGBa> &I, const std::vector<vpImagePoint> &vip, const vpColor &color,
                              unsigned int thickness, bool closed)
{
  DrawPolygon(I, vip, vpRGBa(color.R, color.G, color.B), thickness, closed);
}
 
void vpImageDraw::drawRectangle(vpImage<unsigned char> &I, const vpRect &rectangle, unsigned char color, bool fill,
                                unsigned int thickness)
{
  if (fill) {
    DrawFilledRectangle(I, rectangle, color);
  } else {
    DrawRectangle(I, rectangle, color, thickness);
  }
}
 
void vpImageDraw::drawRectangle(vpImage<vpRGBa> &I, const vpRect &rectangle, const vpColor &color, bool fill,
                                unsigned int thickness)
{
  if (fill) {
    DrawFilledRectangle(I, rectangle, vpRGBa(color.R, color.G, color.B));
  } else {
    DrawRectangle(I, rectangle, vpRGBa(color.R, color.G, color.B), thickness);
  }
}