pxmlw6n2f/Gazebo_Distributed_TCP/gazebo/common/SVGLoader.cc

1157 lines
31 KiB
C++

/*
* Copyright (C) 2015 Open Source Robotics Foundation
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
*/
#include <algorithm>
#include <tinyxml.h>
#include <utility>
#include <cmath>
#include <gazebo/common/Console.hh>
#include <gazebo/common/Assert.hh>
#include "SVGLoaderPrivate.hh"
#include "SVGLoader.hh"
using namespace gazebo;
using namespace common;
/////////////////////////////////////////////////
// This local helper function transforms a string to its lowecase equivalent
std::string lowercase(const std::string &_in)
{
std::string out = _in;
std::transform(out.begin(), out.end(), out.begin(), ::tolower);
return out;
}
/////////////////////////////////////////////////
// This local helper function transforms a C string to its lowecase equivalent
std::string lowercase(const char *_in)
{
std::string ins = _in;
return lowercase(ins);
}
/////////////////////////////////////////////////
// Local helper function that splits a string according to the delimiting char
std::vector<std::string> &split(const std::string &_s,
char _delim,
std::vector<std::string> &_elems)
{
std::stringstream ss(_s);
std::string item;
while (std::getline(ss, item, _delim))
{
_elems.push_back(item);
}
return _elems;
}
/////////////////////////////////////////////////
// This local helper function takes in a SVG transformation string
// and returns the corresponding transformation matrix
ignition::math::Matrix3d ParseTransformMatrixStr(
const std::string &_transformStr)
{
// check for transformation
GZ_ASSERT(!_transformStr.empty(), "no data for ParseTransformMatrixStr");
// _transfromStr should not have a closing paren and look like this
// matrix(0,0.55669897,-0.55669897,0,194.55441,-149.50402
// we're going to extract the transform type and numbers
std::vector<std::string> tx;
split(_transformStr, '(', tx);
if (tx.size() < 2)
{
gzerr << "Invalid path transform: '" << &_transformStr << "'"
<< std::endl;
return ignition::math::Matrix3d::Identity;
}
std::string transform = tx[0];
std::vector<std::string> numbers;
split(tx[1], ',', numbers);
// how to unpack the values into 3x3 matrices
// http://www.w3.org/TR/SVG/coords.html#TransformAttribute
if (transform.find("matrix") != std::string::npos)
{
if (numbers.size() != 6)
{
gzerr << "Unsupported matrix transform with "
<< numbers.size() << " parameters. Should be 6."
<< std::endl;
return ignition::math::Matrix3d::Identity;
}
double a = stod(numbers[0]); // 00
double b = stod(numbers[1]); // 10
double c = stod(numbers[2]); // 01
double d = stod(numbers[3]); // 11
double e = stod(numbers[4]); // 02
double f = stod(numbers[5]); // 12
ignition::math::Matrix3d m(a, c, e, b, d, f, 0, 0, 1);
return m;
}
if (transform.find("skewX") != std::string::npos)
{
if (numbers.size() != 1)
{
gzerr << "Unsupported skewX transform. Needs 1 parameter only"
<< std::endl;
return ignition::math::Matrix3d::Identity;
}
double deg = stod(numbers[0]);
ignition::math::Angle angle;
angle.Degree(deg);
// get the tangent of the angle
double t = tan(angle.Radian());
ignition::math::Matrix3d m(1, t, 0, 0, 1, 0, 0, 0, 1);
return m;
}
if (transform.find("skewY") != std::string::npos)
{
if (numbers.size() != 1)
{
gzerr << "Unsupported skewY transform. Needs 1 parameter only"
<< std::endl;
return ignition::math::Matrix3d::Identity;
}
double deg = stod(numbers[0]);
ignition::math::Angle angle;
angle.Degree(deg);
// get the tangent of the angle
double t = tan(angle.Radian());
ignition::math::Matrix3d m(1, 0, 0, t, 1, 0, 0, 0, 1);
return m;
}
// scale(<x> [<y>])
// if y is not provided, it is assumed to be equal to x.
if (transform.find("scale") != std::string::npos)
{
if (numbers.size() == 0 || numbers.size() > 2)
{
gzerr << "Unsupported scale transform with more than 2 parameters"
<< std::endl;
return ignition::math::Matrix3d::Identity;
}
double x = stod(numbers[0]);
double y = x;
if (numbers.size() == 2)
{
y = stod(numbers[1]);
}
ignition::math::Matrix3d m(x, 0, 0, 0, y, 0, 0, 0, 1);
return m;
}
// translate(<x> [<y>])
// If y is not provided, it is assumed to be zero.
if (transform.find("translate") != std::string::npos)
{
if (numbers.size() == 0 || numbers.size() > 2)
{
gzerr << "Unsupported translate transform with more than 2 parameters"
<< std::endl;
return ignition::math::Matrix3d::Identity;
}
double x = stod(numbers[0]);
double y = 0;
if (numbers.size() == 2)
{
y = stod(numbers[1]);
}
ignition::math::Matrix3d m(1, 0, x, 0, 1, y, 0, 0, 1);
return m;
}
// rotate(<a> [<x> <y>]) angle in degrees, center x and y
// if x, y are not supplied, rotation is about 0, 0
if (transform.find("rotate") != std::string::npos)
{
if (numbers.size() ==0 || numbers.size() == 2 || numbers.size() > 3 )
{
gzerr << "Unsupported rotate transform. Only angle and optional x y"
<< " are supported" << std::endl;
return ignition::math::Matrix3d::Identity;
}
double deg = stod(numbers[0]);
ignition::math::Angle angle;
angle.Degree(deg);
double a = angle.Radian();
double sina = sin(a);
double cosa = cos(a);
double x = 0;
double y = 0;
if (numbers.size() == 3)
{
x = stod(numbers[1]);
y = stod(numbers[2]);
}
// we apply a translation to x, y, the rotation and the translation -x,-y
ignition::math::Matrix3d transToXy(1, 0, x, 0, 1, y, 0, 0, 1);
ignition::math::Matrix3d transFromXy(1, 0, -x, 0, 1, -y, 0, 0, 1);
ignition::math::Matrix3d rotate(cosa, -sina, 0, sina, cosa, 0, 0, 0, 1);
ignition::math::Matrix3d m = transToXy * rotate * transFromXy;
return m;
}
// we have no business being here
gzerr << "Unknown transformation: " << transform << std::endl;
ignition::math::Matrix3d m = ignition::math::Matrix3d::Identity;
return m;
}
/////////////////////////////////////////////////
// This local helper function interpolates a bezier curve at t (between 0 and 1)
ignition::math::Vector2d bezierInterpolate(double _t,
const ignition::math::Vector2d &_p0,
const ignition::math::Vector2d &_p1,
const ignition::math::Vector2d &_p2,
const ignition::math::Vector2d &_p3)
{
double t_1 = 1.0 - _t;
double t_1_2 = t_1 * t_1;
double t_1_3 = t_1_2 * t_1;
double t2 = _t * _t;
double t3 = t2 * _t;
ignition::math::Vector2d p;
p.X(t_1_3 * _p0.X() + 3 * _t * t_1_2 * _p1.X() + 3 * t2 * t_1 * _p2.X() +
t3 * _p3.X());
p.Y(t_1_3 * _p0.Y() + 3 * _t * t_1_2 * _p1.Y() + 3 * t2 * t_1 * _p2.Y() +
t3 * _p3.Y());
return p;
}
/////////////////////////////////////////////////
// This helper function adds bezier interpolations to a list of points
void cubicBezier(const ignition::math::Vector2d &_p0,
const ignition::math::Vector2d &_p1,
const ignition::math::Vector2d &_p2,
const ignition::math::Vector2d &_p3,
double _step,
std::vector<ignition::math::Vector2d> &_points)
{
// we don't start at t = 0, but t = step...
// so we assume that the first point is there (from the last move)
double t = _step;
while (t < 1.0)
{
auto p = bezierInterpolate(t, _p0, _p1, _p2, _p3);
_points.push_back(p);
t += _step;
}
// however we close the loop with the last point (t = 1)
_points.push_back(_p3);
}
/////////////////////////////////////////////////
// This helper function computes the square of a number
static double Sqr(float _x)
{
return _x * _x;
}
/////////////////////////////////////////////////
// This helper function computes the angle between 2 vectors, using acos
static float VecAng(float _ux, float _uy, float _vx, float _vy)
{
double ux = _ux;
double uy = _uy;
double vx = _vx;
double vy = _vy;
double uMag = sqrt(ux * ux + uy * uy);
double vMag = sqrt(vx * vx + vy * vy);
double r = (ux * vx + uy * vy) / (uMag * vMag);
if (r < -1.0)
{
r = -1.0;
}
else if (r > 1.0)
{
r = 1.0;
}
double a = acos(r);
if (ux * vy < uy * vx)
{
return -a;
}
else
{
return a;
}
}
/////////////////////////////////////////////////
// This helper function adds arc interpolations to a list of points
void arcPath(const ignition::math::Vector2d &_p0,
const double _rx,
const double _ry,
const double _rotxDeg,
const size_t _largeArc,
const size_t _sweepDirection,
const ignition::math::Vector2d &_pEnd,
const double _step,
std::vector<ignition::math::Vector2d> &_points)
{
// Ported from canvg (https://code.google.com/p/canvg/)
double rx = _rx;
double ry = _ry;
double rotx = _rotxDeg / 180.0 * M_PI;
double x1, y1, x2, y2, cx, cy, dx, dy, d;
double x1p, y1p, cxp, cyp, s, sa, sb;
double ux, uy, vx, vy, a1, da;
double px = 0, py = 0, ptanx = 0, ptany = 0, t[6];
double sinrx, cosrx;
double hda, kappa;
x1 = _p0.X();
y1 = _p0.Y();
x2 = _pEnd.X();
y2 = _pEnd.Y();
dx = x1 - x2;
dy = y1 - y2;
d = sqrt(dx*dx + dy*dy);
if (d < 1e-6 || rx < 1e-6 || ry < 1e-6)
{
// The arc degenerates to a line
_points.push_back(_pEnd);
return;
}
sinrx = sin(rotx);
cosrx = cos(rotx);
// Convert to center point parameterization.
// http://www.w3.org/TR/SVG11/implnote.html#ArcImplementationNotes
// 1) Compute x1', y1'
x1p = cosrx * dx / 2.0 + sinrx * dy / 2.0;
y1p = -sinrx * dx / 2.0 + cosrx * dy / 2.0;
d = Sqr(x1p) / Sqr(rx) + Sqr(y1p) / Sqr(ry);
if (d > 1)
{
d = sqrt(d);
rx *= d;
ry *= d;
}
// 2) Compute cx', cy'
s = 0.0;
sa = Sqr(rx) * Sqr(ry) - Sqr(rx) * Sqr(y1p) - Sqr(ry) * Sqr(x1p);
sb = Sqr(rx) * Sqr(y1p) + Sqr(ry) * Sqr(x1p);
if (sa < 0.0)
sa = 0.0;
if (sb > 0.0)
s = sqrt(sa / sb);
if (_largeArc == _sweepDirection)
{
s = -s;
}
cxp = s * rx * y1p / ry;
cyp = s * -ry * x1p / rx;
// 3) Compute cx,cy from cx',cy'
cx = (x1 + x2) / 2.0 + cosrx * cxp - sinrx * cyp;
cy = (y1 + y2) / 2.0 + sinrx * cxp + cosrx * cyp;
// 4) Calculate theta1, and delta theta.
ux = (x1p - cxp) / rx;
uy = (y1p - cyp) / ry;
vx = (-x1p - cxp) / rx;
vy = (-y1p - cyp) / ry;
// initial angle
a1 = VecAng(1.0, 0.0, ux, uy);
// delta angle
da = VecAng(ux, uy, vx, vy);
if (_largeArc)
{
// Choose large arc
if (da > 0.0)
da = da - 2 * M_PI;
else
da = 2 * M_PI + da;
}
// rounding errors for half circles
if (M_PI - fabs(da) < 0.001)
{
if (_sweepDirection)
da = M_PI;
else
da = -M_PI;
}
// Approximate the arc using cubic spline segments.
t[0] = cosrx;
t[1] = sinrx;
t[2] = -sinrx;
t[3] = cosrx;
t[4] = cx;
t[5] = cy;
// Split arc into max 90 degree segments.
// The loop assumes an iteration per end point
// (including start and end), this +1.
size_t ndivs = static_cast<int>(fabs(da) / (M_PI * 0.5) + 1.0);
hda = (da / ndivs) / 2.0;
kappa = fabs(4.0 / 3.0 * (1.0 - cos(hda)) / sin(hda));
if (da < 0.0)
kappa = -kappa;
for (size_t i = 0; i <= ndivs; ++i)
{
double x, y, tanx, tany, a;
a = a1 + da * (1.0 * i /ndivs);
dx = cos(a);
dy = sin(a);
// position xform point
double pox = dx * rx;
double poy = dy * ry;
x = pox * t[0] + poy * t[2] + t[4];
y = pox * t[1] + poy * t[3] + t[5];
// tangent xform vec
double tx = -dy * rx * kappa;
double ty = dx * ry * kappa;
tanx = tx * t[0] + ty * t[2];
tany = tx * t[1] + ty * t[3];
if (i > 0)
{
ignition::math::Vector2d p0(px, py);
ignition::math::Vector2d p1(px + ptanx, py + ptany);
ignition::math::Vector2d p2(x - tanx, y - tany);
ignition::math::Vector2d p3(x, y);
cubicBezier(p0, p1, p2, p3, _step, _points);
}
px = x;
py = y;
ptanx = tanx;
ptany = tany;
}
}
/////////////////////////////////////////////////
SvgError::SvgError(const std::string &_what)
: std::runtime_error(_what)
{
}
/////////////////////////////////////////////////
ignition::math::Vector2d SVGLoader::SubpathToPolyline(
const std::vector<SVGCommand> &_subpath,
ignition::math::Vector2d _last,
std::vector<ignition::math::Vector2d> &_polyline)
{
GZ_ASSERT(_polyline.size() == 0, "polyline not empty");
for (SVGCommand cmd: _subpath)
{
size_t i = 0;
size_t count = cmd.numbers.size();
switch (cmd.cmd)
{
case 'm':
case 'l':
while (i < count)
{
ignition::math::Vector2d p;
p.X(cmd.numbers[i+0]);
p.Y(cmd.numbers[i+1]);
// m and l cmds are relative to the last point
p.X() += _last.X();
p.Y() += _last.Y();
_polyline.push_back(p);
_last = p;
i += 2;
}
break;
case 'M':
case 'L':
while (i < count)
{
ignition::math::Vector2d p;
p.X(cmd.numbers[i+0]);
p.Y(cmd.numbers[i+1]);
_polyline.push_back(p);
_last = p;
i += 2;
}
break;
case 'C':
while (i < count)
{
ignition::math::Vector2d p0 = _last;
ignition::math::Vector2d p1, p2, p3;
p1.X(cmd.numbers[i+0]);
p1.Y(cmd.numbers[i+1]);
p2.X(cmd.numbers[i+2]);
p2.Y(cmd.numbers[i+3]);
p3.X(cmd.numbers[i+4]);
p3.Y(cmd.numbers[i+5]);
cubicBezier(p0, p1, p2, p3, this->dataPtr->resolution, _polyline);
_last = p3;
i += 6;
}
break;
case 'c':
while (i < count)
{
ignition::math::Vector2d p0 = _last;
ignition::math::Vector2d p1, p2, p3;
p1.X(cmd.numbers[i+0] + _last.X());
p1.Y(cmd.numbers[i+1] + _last.Y());
p2.X(cmd.numbers[i+2] + _last.X());
p2.Y(cmd.numbers[i+3] + _last.Y());
p3.X(cmd.numbers[i+4] + _last.X());
p3.Y(cmd.numbers[i+5] + _last.Y());
cubicBezier(p0, p1, p2, p3, this->dataPtr->resolution, _polyline);
_last = p3;
i += 6;
}
break;
case 'A':
while (i < count)
{
ignition::math::Vector2d p0 = _last;
double rx = cmd.numbers[i+0];
double ry = cmd.numbers[i+1];
double xRot = cmd.numbers[i+2];
unsigned int arc(cmd.numbers[i+3]);
unsigned int sweep(cmd.numbers[i+4]);
ignition::math::Vector2d pEnd;
pEnd.X(cmd.numbers[i+5]);
pEnd.Y(cmd.numbers[i+6]);
arcPath(p0, rx, ry, xRot, arc, sweep, pEnd,
this->dataPtr->resolution, _polyline);
_last = pEnd;
i += 7;
}
break;
case 'a':
while (i < count)
{
ignition::math::Vector2d p0 = _last;
double rx = cmd.numbers[i+0];
double ry = cmd.numbers[i+1];
double xRot = cmd.numbers[i+2];
unsigned int arc(cmd.numbers[i+3]);
unsigned int sweep(cmd.numbers[i+4]);
ignition::math::Vector2d pEnd;
pEnd.X(cmd.numbers[i+5] + _last.X());
pEnd.Y(cmd.numbers[i+6] + _last.Y());
arcPath(p0, rx, ry, xRot, arc, sweep, pEnd,
this->dataPtr->resolution, _polyline);
_last = pEnd;
i += 7;
}
// Z and z indicate closed path.
// just add the first point to the list
case 'Z':
case 'z':
{
auto &p = _polyline.front();
if (_polyline.back().Distance(p) > 1e-5)
{
gzerr << "Zz" << _polyline.back().Distance(p) << std::endl;
_polyline.push_back(p);
}
break;
}
default:
gzerr << "Unexpected SVGCommand value: " << cmd.cmd << std::endl;
}
}
return _last;
}
/////////////////////////////////////////////////
SVGLoader::SVGLoader(unsigned int _samples)
{
this->dataPtr = new SVGLoaderPrivate();
if (_samples == 0)
{
std::string m("The number of samples cannot be 0");
SvgError e(m);
throw e;
}
this->dataPtr->resolution = 1.0/_samples;
}
/////////////////////////////////////////////////
SVGLoader::~SVGLoader()
{
delete(this->dataPtr);
}
/////////////////////////////////////////////////
void SVGLoader::SplitSubpaths(const std::vector<SVGCommand> &_cmds,
std::vector< std::vector<SVGCommand> > &_subpaths)
{
if (_cmds.empty())
{
std::ostringstream os;
os << "SVGPath has no commands";
SvgError x(os.str());
throw x;
}
for (SVGCommand cmd: _cmds)
{
if (tolower(cmd.cmd) == 'm')
{
// the path contains a subpath
std::vector<SVGCommand> sub;
_subpaths.push_back(sub);
}
// get a reference to the latest subpath
std::vector<SVGCommand> &subpath = _subpaths.back();
// give the cmd to the latest
subpath.push_back(cmd);
}
}
/////////////////////////////////////////////////
void SVGLoader::ExpandCommands(
const std::vector< std::vector<SVGCommand> > &_subpaths,
SVGPath &_path)
{
for (std::vector<SVGCommand> compressedSubpath :_subpaths)
{
// add new subpath
_path.subpaths.push_back(std::vector<SVGCommand>());
// get a reference
std::vector<SVGCommand> &subpath = _path.subpaths.back();
// copy the cmds with repeating commands, grouping the numbers
for (SVGCommand xCmd : compressedSubpath)
{
unsigned int numberCount = 0;
if (tolower(xCmd.cmd) == 'a')
numberCount = 7;
if (tolower(xCmd.cmd) == 'c')
numberCount = 6;
if (tolower(xCmd.cmd) == 'm')
numberCount = 2;
if (tolower(xCmd.cmd) == 'l')
numberCount = 2;
if (tolower(xCmd.cmd) == 'v')
numberCount = 1;
if (tolower(xCmd.cmd) == 'h')
numberCount = 1;
if (tolower(xCmd.cmd) == 'z')
subpath.push_back(xCmd);
// group numbers together and repeat the command
// for each group
unsigned int n = 0;
size_t size = xCmd.numbers.size();
while (n < size)
{
subpath.push_back(SVGCommand());
SVGCommand &cmd = subpath.back();
cmd.cmd = xCmd.cmd;
for (size_t i = 0; i < numberCount; ++i)
{
cmd.numbers.push_back(xCmd.numbers[i+n]);
}
n += numberCount;
}
}
}
}
/////////////////////////////////////////////////
void SVGLoader::GetPathCommands(const std::vector<std::string> &_tokens,
SVGPath &_path)
{
std::vector <SVGCommand> cmds;
std::string lookup = "aAcCmMqQlLvVhHzZ";
char lastCmd = 'x';
std::vector<double> numbers;
for (std::string token: _tokens)
{
// new command?
if (lookup.find(token[0]) == std::string::npos)
{
// its just numbers
std::vector<std::string> numberStrs;
split(token, ',', numberStrs);
for (std::string numberStr : numberStrs)
{
double f = atof(numberStr.c_str());
numbers.push_back(f);
}
}
else
{
if (lastCmd != 'x')
{
SVGCommand c;
c.cmd = lastCmd;
c.numbers = numbers;
cmds.push_back(c);
}
// its new command
lastCmd = token[0];
numbers.resize(0);
}
}
// the last command
if (lastCmd != 'x')
{
SVGCommand c;
c.cmd = lastCmd;
c.numbers = numbers;
cmds.push_back(c);
}
// split the commands into sub_paths
std::vector< std::vector< SVGCommand> > subpaths;
this->SplitSubpaths(cmds, subpaths);
this->ExpandCommands(subpaths, _path);
// the starting point for the subpath
// it is the end point of the previous one
ignition::math::Vector2d p;
for (std::vector<SVGCommand> subpath : subpaths)
{
_path.polylines.push_back(std::vector<ignition::math::Vector2d>());
std::vector<ignition::math::Vector2d> &polyline = _path.polylines.back();
p = this->SubpathToPolyline(subpath, p, polyline);
}
// if necessary, apply transform to p and polyline
if (_path.transform != ignition::math::Matrix3d::Identity)
{
// we need to transform all the points in the path
for (auto &polyline : _path.polylines)
{
for (auto &polyPoint : polyline)
{
// make a 3d vector form the 2d point
ignition::math::Vector3d point3(polyPoint.X(), polyPoint.Y(), 1);
// matrix multiply to get the new point, then save new coords in place
auto transformed = _path.transform * point3;
polyPoint.X(transformed.X());
polyPoint.Y(transformed.Y());
}
}
}
}
/////////////////////////////////////////////////
void SVGLoader::GetPathAttribs(TiXmlElement *_pElement, SVGPath &_path)
{
GZ_ASSERT(_pElement, "empty XML element where a path was expected");
_path.transform = ignition::math::Matrix3d::Identity;
TiXmlAttribute *pAttrib = _pElement->FirstAttribute();
// this attribute contains a list of coordinates
std::vector<std::string> tokens;
while (pAttrib)
{
std::string name = lowercase(pAttrib->Name());
std::string value = pAttrib->Value();
if (name == "style")
{
_path.style = value;
}
else if (name == "id")
{
_path.id = value;
}
else if (name == "transform")
{
_path.transform = ParseTransformMatrixStr(value);
}
else if (name == "d")
{
// load in the path parameters
split(value, ' ', tokens);
}
else
{
gzwarn << "Ignoring attribute \"" << name << "\" in path" << std::endl;
}
pAttrib = pAttrib->Next();
}
// Now that all attributes are loaded, we can compute the values
this->GetPathCommands(tokens, _path);
}
/////////////////////////////////////////////////
void SVGLoader::GetSvgPaths(TiXmlNode *_pParent, std::vector<SVGPath> &_paths)
{
if (!_pParent)
return;
TiXmlNode *pChild;
int t = _pParent->Type();
std::string name;
if ( t == TiXmlNode::TINYXML_ELEMENT)
{
name = lowercase(_pParent->Value());
if (name == "path")
{
TiXmlElement *element = _pParent->ToElement();
SVGPath p;
this->GetPathAttribs(element, p);
_paths.push_back(p);
}
// skip defs node that can contain path
// elements that are not actual paths.
if (name == "defs")
{
return;
}
}
for (pChild = _pParent->FirstChild();
pChild != 0;
pChild = pChild->NextSibling())
{
this->GetSvgPaths(pChild, _paths);
}
}
/////////////////////////////////////////////////
bool SVGLoader::Parse(const std::string &_filename,
std::vector<SVGPath> &_paths)
{
try
{
// load the named file and dump its structure to STDOUT
TiXmlDocument doc(_filename.c_str());
if (!doc.LoadFile())
{
std::ostringstream os;
gzerr << "Failed to load file " << _filename << std::endl;
gzerr << os.str() << std::endl;
return false;
}
this->GetSvgPaths(&doc, _paths);
return true;
}
catch(SvgError &e)
{
gzerr << e.what() << std::endl;
}
return false;
}
/////////////////////////////////////////////////
void SVGLoader::DumpPaths(const std::vector<SVGPath> &_paths,
std::ostream &_out) const
{
// this prints an html document that allows to debug
// SVG parsing issues. The points are generated in
// a loop between the header and footer.
std::string header = R"***(
<!DOCTYPE html>
<html>
<script type="text/javascript">
)***";
std::string footer = R"***(
</script>
<script>
var x0 = 0;
var y0 = 0;
var scale = 1.;
function xx(x)
{
var r = x0 + scale * x;
return r;
}
function yy(y)
{
var r = - (y0 + scale * (-y) );
return r;
}
function drawPoint(ctx, x, y)
{
ctx.beginPath();
ctx.arc(x, y, 5, 0, 2 * Math.PI, true);
ctx.strokeStyle= style;
ctx.stroke();
}
function drawPath(ctx, path, style, x0, y0, scale, showCtrlPoints )
{
console.log('drawPath ' + path.name);
ctx.beginPath();
for (var j = 0; j < path.subpaths.length; ++j)
{
var points = path.subpaths[j];
console.log(points.length + ' points in subpath, (' + style + ')');
if (points.length < 2)
{
console.log("not enough points in subpath " + j);
return;
}
ctx.moveTo(xx(points[0][0]), yy(points[0][1]));
for (var i = 1; i < points.length; ++i)
{
var x= xx(points[i][0]);
var y= yy(points[i][1]);
ctx.lineTo(x, y);
}
ctx.strokeStyle= style;
ctx.stroke();
// draw points
if (showCtrlPoints)
{
var styles = ["black", "orange", "grey"];
for (var i = 0; i < points.length; ++i)
{
var x= xx(points[i][0]);
var y= yy(points[i][1]);
var m = " [" + points[i][0] + ", " + points[i][1];
m += "] [" + x + ", " + y + "]";
console.log(m);
ctx.beginPath();
if (i == 0)
{
ctx.arc(x, y, 4, 0, 2 * Math.PI, true);
ctx.strokeStyle = "red";
ctx.fill();
}
else if (i == 1)
{
ctx.arc(x, y, 2, 0, 2 * Math.PI, true);
ctx.strokeStyle= "red";
}
else
{
ctx.arc(x, y, 2, 0, 2 * Math.PI, true);
ctx.strokeStyle= styles[i % styles.length ];
}
ctx.stroke();
}
}
}
}
function draw(showCtrlPoints)
{
var canvas = document.getElementById("myCanvas");
var ctx = canvas.getContext("2d");
var styles = ["red", "green", "blue"];
ctx.clearRect(0, 0, canvas.width, canvas.height);
x0 = Number(document.getElementsByName("xoff_in")[0].value);
y0 = Number(document.getElementsByName("yoff_in")[0].value);
scale = Number(document.getElementsByName("scale_in")[0].value);
for (var i =0; i < svg.length; ++i)
{
var path = svg[i];
console.log("path: " + path.name);
drawPath(ctx, path, styles[i%3], x0, y0, scale, showCtrlPoints);
}
}
console.log("number of paths: " + svg.length);
document.addEventListener("DOMContentLoaded", function(event)
{
draw();
});
</script>
<body>
<div>
Xoff: <input type="text" name="xoff_in" value="0"><br>
Yoff: <input type="text" name="yoff_in" value="0"><br>
Scale: <input type="text" name="scale_in" value="1.0"><br>
<button onclick="draw(true);">Draw</button>
</div>
<canvas
id="myCanvas"
width="1024"
height="768"
style="border:1px solid #d3d3d3;">
Your browser does not support the canvas element.
</canvas>
</body>
</html>
)***";
_out << header << std::endl;
_out << "var svg = [];" << std::endl;
for (SVGPath path : _paths)
{
_out << "svg.push({name:\"" << path.id;
_out << "\", subpaths:[], style: \"";
_out << path.style << "\"}); " << std::endl;
_out << "svg[svg.length-1].subpaths = [";
char psep = ' ';
for (unsigned int i = 0; i < path.polylines.size(); ++i)
{
std::vector<ignition::math::Vector2d> poly = path.polylines[i];
_out << psep << "[" << std::endl;
psep = ',';
char sep = ' ';
for (ignition::math::Vector2d p : poly)
{
_out << " " << sep << " [" << p.X() << ", "
<< p.Y() << "]" <<std::endl;
sep = ',';
}
_out << " ] " << std::endl;
}
_out << "];" << std::endl;
_out << "\n\n";
}
_out << footer << std::endl;
}
/////////////////////////////////////////////////
bool Vector2dCompare(const ignition::math::Vector2d &_a,
const ignition::math::Vector2d &_b,
double _tol)
{
double x = _a.X() - _b.X();
double y = _a.Y() - _b.Y();
// is squared distance smaller than squared tolerance?
return (x*x + y*y < _tol * _tol);
}
/////////////////////////////////////////////////
void SVGLoader::PathsToClosedPolylines(
const std::vector<common::SVGPath> &_paths,
double _tol,
std::vector< std::vector<ignition::math::Vector2d> > &_closedPolys,
std::vector< std::vector<ignition::math::Vector2d> > &_openPolys)
{
// first we extract all polyline into a vector of line segments
std::list<std::pair<ignition::math::Vector2d,
ignition::math::Vector2d> > segments;
for (auto const &path : _paths)
{
for (auto const &poly : path.polylines)
{
ignition::math::Vector2d startPoint = poly[0];
for (unsigned int i =1; i < poly.size(); ++i)
{
const ignition::math::Vector2d &endPoint = poly[i];
double length = endPoint.Distance(startPoint);
if (length < _tol)
{
gzmsg << "Ignoring short segment (length: "
<< length << ")" <<std::endl;
}
else
{
segments.push_back(std::make_pair(startPoint, endPoint));
startPoint = endPoint;
}
}
}
}
// then we remove segments until there are none left
while (!segments.empty())
{
// start a new polyline, made from the 2 points of
// the next available segment.
std::vector<ignition::math::Vector2d> polyline;
auto &s = segments.front();
polyline.push_back(s.first);
polyline.push_back(s.second);
// remove the segment from the list
segments.pop_front();
// this flag will be false if the polyline has no
// new segment
bool segmentFound = true;
// this flag is true when the polyline is closed
bool loopClosed = false;
while (segmentFound && !loopClosed)
{
// find the segment in the polyline
segmentFound = false;
for (auto it = segments.begin(); it != segments.end(); ++it)
{
auto seg = *it;
ignition::math::Vector2d nextPoint;
if (Vector2dCompare(polyline.back(), seg.first, _tol))
{
nextPoint = seg.second;
segmentFound = true;
}
if (Vector2dCompare(polyline.back(), seg.second, _tol))
{
nextPoint = seg.first;
segmentFound = true;
}
if (segmentFound)
{
// remove the segment from the list of all remaining segments
segments.erase(it);
// add the new point to the polyline
polyline.push_back(nextPoint);
// verify if the polyline is closed
if (Vector2dCompare(nextPoint, polyline[0], _tol))
{
// the loop is closed, we don't need another segment
loopClosed = true;
}
// the segment has been found
// get out of the for loop.
break;
}
}
}
// the new polyline is complete
if (loopClosed)
{
_closedPolys.push_back(polyline);
}
else
{
gzmsg << "Line segments that are not part of a closed paths have"
<< " been found with the current minimum distance of " << _tol
<< " between 2 points." << std::endl << std::endl;
_openPolys.push_back(polyline);
}
}
}