using System;
using System.Collections.Generic;
//using System.Drawing;
using System.Globalization;
using System.Windows;
using System.Linq;
using System.Text;
using System.Text.RegularExpressions;
using System.Threading.Tasks;
namespace SketchAssistantWPF
{
public class FileImporter
{
///
/// scale factor for coordinates of svg file
///
double scale;
///
/// line pointer for the current svg document
///
int i;
///
/// array containing all characters interpreted as whitespaces which seperate words/tokens in the input file
///
readonly char[] whitespaces = new char[] { ' ', ',' };
///
/// number of points to create along the outline of an ellipse, divisible by 4
///
readonly int samplingRateEllipse = 12;
///
/// number of points to create on a bezier curve, including start and end point (even number will result in "flat" bezier curves, uneven number in "pointed" ones)
///
readonly int samplingRateBezier = 101;
///
/// parses a drawing consisting of line objects, given as a file in the application specific .isad format
///
/// the path of the input file
/// the width and height of the left canvas and the parsed picture as a list of lines
public Tuple> ParseISADInputFile(String fileName)
{
return ParseISADInput(System.IO.File.ReadAllLines(fileName));
}
///
/// parses a drawing consisting of line objects, given as the content of a .isad file, seperated into lines
///
/// an array holding all lines of the input file
/// the width and height of the left canvas and the parsed picture as a list of lines
private Tuple> ParseISADInput(String[] allLines)
{
if (allLines.Length == 0)
{
throw new FileImporterException("file is empty", "", -1);
}
if (!"drawing".Equals(allLines[0]))
{
throw new FileImporterException("file is not an interactive sketch assistant drawing", ".isad files have to start with the 'drawing' token", 1);
}
if (!"enddrawing".Equals(allLines[allLines.Length - 1]))
{
throw new FileImporterException("unterminated drawing definition", ".isad files have to end with the 'enddrawing' token", allLines.Length);
}
Tuple dimensions = ParseISADHeader(allLines);
List picture = ParseISADBody(allLines, dimensions.Item1, dimensions.Item2);
return new Tuple>(dimensions.Item1, dimensions.Item2, picture);
}
///
/// parses the first two lines of an input file in .isad format
///
/// the input file as an array of lines
/// the width and height of the left canvas
private Tuple ParseISADHeader(String[] allLines)
{
int width;
int height;
if (!(allLines.Length > 1) || !Regex.Match(allLines[1], @"^\d+x?\d+$", RegexOptions.None).Success)
{
throw new FileImporterException("invalid or missing canvas size definition", "format: [width]x[heigth]", 2);
}
String[] size = allLines[1].Split('x');
width = Convert.ToInt32(size[0]);
height = Convert.ToInt32(size[1]);
return new Tuple(width, height);
}
///
/// parses all line entries of an input file in .isad format
///
/// the input file as an array of lines
/// the parsed picture as a list of lines
private List ParseISADBody(String[] allLines, int width, int height)
{
String lineStartString = "line";
String lineEndString = "endline";
List drawing = new List();
//number of the line currently being parsed, enumeration starting at 0, body starts at the third line, therefore lin number 2
int i = 2;
//parse 'line' token and complete line definition
int lineStartPointer = i;
//holds the line number of the next expected beginning of a line definition, or of the enddrawing token
while (lineStartString.Equals(allLines[i]))
{
//start parsing next line
i++;
List newLine = new List();
while (!lineEndString.Equals(allLines[i]))
{
if (i == allLines.Length)
{
throw new FileImporterException("unterminated line definition", null, (i + 1));
}
//parse single point definition
if (!Regex.Match(allLines[i], @"^\d+;\d+$", RegexOptions.None).Success)
{
throw new FileImporterException("invalid Point definition: wrong format", "format: [xCoordinate];[yCoordinate]", (i + 1));
}
String[] coordinates = allLines[i].Split(';');
//no errors possible, convertability to int already checked above
int xCoordinate = Convert.ToInt32(coordinates[0]);
int yCoordinate = Convert.ToInt32(coordinates[1]);
if (xCoordinate < 0 || yCoordinate < 0 || xCoordinate > width - 1 || yCoordinate > height - 1)
{
throw new FileImporterException("invalid Point definition: point out of bounds", null, (i + 1));
}
newLine.Add(new Point(xCoordinate, yCoordinate));
//start parsing next line
i++;
}
//"parse" 'endline' token, syntax already checked at the beginning, and start parsing next line
i++;
//add line to drawing
drawing.Add(new InternalLine(newLine));
//update lineStartPointer to the presumable start of the next line
lineStartPointer = i;
}
//check if end of body is reached after there are no more line definitions
if (i != allLines.Length - 1)
{
throw new FileImporterException("missing or invalid line definition token", "line definitions start with the 'line' token", (i + 1));
}
//return parsed picture
return drawing;
}
///
/// connection point for testing use only: calls ParseISADInput(String[] allLines) and directly passes the given argument (effectively bypassing the File Input functionality)
///
/// an array holding all lines of the input file
/// the width and height of the left canvas and the parsed picture as a list of lines
public Tuple> ParseISADInputForTesting(String[] allLines)
{
return ParseISADInput(allLines);
}
///
/// parses a svg drawing, given as a .svg file
/// several severe restrictions to the svg standard apply:
/// - width and heigth values must be integers
/// - the supported svg elements to be drawn must be placed on top level directly inside the 'svg' tag
/// - except for the global 'svg' tag, no hierarchical elements (elements which contain other svg elements) may exist. in other words: after an opening element tag no other opening element tag may occur before the closing tag of this element.
/// - lines in front of the (single) opening and after the (single) closing global svg tag will be ignored during parsing
/// - unsupported svg elements on top level will be ignored during parsing
/// - the input file must not contain empty lines
/// - all input files have to be manually tested and approved for use with this program by a developer or otherwise entitled personnel, otherwise no guarantee about correct and error-free parsing will be given
///
/// the path of the input file
/// the width and height of the left canvas and the parsed picture as a list of lines
public Tuple> ParseSVGInputFile(String fileName, int windowWidth, int windowHeight)
{
return ParseSVGInput(System.IO.File.ReadAllLines(fileName), windowWidth, windowHeight);
}
///
/// parses a svg drawing, given as the content of a .svg file, seperated into lines
///
/// an array holding all lines of the input file
/// the width and height of the left canvas and the parsed picture as a list of lines
private Tuple> ParseSVGInput(String[] allLines, double windowWidth, double windowHeight)
{
i = 0; //reset line pointer
if (allLines.Length == 0) //check for empty file
{
throw new FileImporterException("file is empty", "", -1);
}
var sizedef = ParseSVGHeader(allLines); //parse svg file header and get internal coordinate range
i++;
int width; //width of the resulting picture in pixels
int height; //height of the resulting picture in pixels
if (windowWidth != 0 && windowHeight != 0)
{
if (windowWidth / windowHeight > sizedef.Item1 / sizedef.Item2) //height dominant, width has to be smaller than drawing window to preserve xy-scale
{
scale = windowHeight / sizedef.Item2;
height = (int)Math.Round(windowHeight);
width = (int)Math.Round(scale * sizedef.Item1);
}
else //width dominant, height has to be smaller than drawing window to preserve xy-scale
{
scale = windowWidth / sizedef.Item1;
width = (int)Math.Round(windowWidth);
height = (int)Math.Round(scale * sizedef.Item2);
}
}
else
{
scale = 1;
width = sizedef.Item1;
height = sizedef.Item2;
}
for (int j = 0; j < allLines.Length; j++)
{
allLines[j] = allLines[j].Trim(whitespaces);
}
List picture = ParseSVGBody(allLines); //parse whole svg drawing into list of lines
return new Tuple>(width, height, picture);
}
///
/// parses the svg file header and returns the internal coordinate range of this drawing, and iterates i to point to the start of svg element definitions
///
/// an array holding all lines of the input file
/// the internal coordinate range of this drawing
private Tuple ParseSVGHeader(String[] allLines)
{
while (!allLines[i].StartsWith("(width, height);
}
///
/// parses all relevant svg element definitions and skips the ones not representable by the sketch assistant
///
/// an array holding all lines of the input file
/// the parsed picture as a list of lines
private List ParseSVGBody(String[] allLines)
{
List picture = new List();
while (!allLines[i].StartsWith(" element = ParseSingleSVGElement(allLines);
if (element != null)
{
picture.AddRange(element);
}
i++;
if (i > allLines.Length - 1) throw new FileImporterException("unterminated input file: missing tag", "the file must not contain empty lines", i + 1);
}
return picture;
}
///
/// parses one toplevel svg element
///
/// an array holding all lines of the input file
/// the parsed Element as a list of lines
private List ParseSingleSVGElement(string[] allLines)
{
String[] currentElement = GetCurrentElement(allLines);
return ParseSingleLineSVGElement(currentElement);
}
///
/// parses a single toplevel svg element only taking one line
///
/// an array holding all lines of the input file
/// the parsed element as a Line object, or null if the element is not supported
private List ParseSingleLineSVGElement(string[] currentElement)
{
List points = null;
List element = null;
switch (currentElement[0])
{
case "();
element.Add(new InternalLine(points));
}
return element;
}
///
/// parses a rectangle definition into a List of Points representing a single line around the rectangle (in clockwise direction), ignoring rounded corners
///
/// the definition of the element as whitespace seperated String[]
/// the parsed element as a List of Points
private List ParseRect(string[] currentElement)
{
double x = 0;
double y = 0;
double w = 0;
double h = 0;
double rx = 0;
double ry = 0;
for (int j = 0; j < currentElement.Length; j++)
{
if (currentElement[j].StartsWith("x="))
{
x = Convert.ToDouble(ParseSingleSVGAttribute(currentElement[j]), CultureInfo.InvariantCulture);
}
else if (currentElement[j].StartsWith("y="))
{
y = Convert.ToDouble(ParseSingleSVGAttribute(currentElement[j]), CultureInfo.InvariantCulture);
}
else if (currentElement[j].StartsWith("width="))
{
w = Convert.ToDouble(ParseSingleSVGAttribute(currentElement[j]), CultureInfo.InvariantCulture);
}
else if (currentElement[j].StartsWith("height="))
{
h = Convert.ToDouble(ParseSingleSVGAttribute(currentElement[j]), CultureInfo.InvariantCulture);
}
else if (currentElement[j].StartsWith("rx="))
{
rx = Convert.ToDouble(ParseSingleSVGAttribute(currentElement[j]), CultureInfo.InvariantCulture);
}
else if (currentElement[j].StartsWith("ry="))
{
ry = Convert.ToDouble(ParseSingleSVGAttribute(currentElement[j]), CultureInfo.InvariantCulture);
}
}
List rect = new List();
rect.Add(ScaleAndCreatePoint(x, y));
rect.Add(ScaleAndCreatePoint(x + w, y));
rect.Add(ScaleAndCreatePoint(x + w, y + h));
rect.Add(ScaleAndCreatePoint(x, y + h));
rect.Add(ScaleAndCreatePoint(x, y));
return rect;
}
///
/// parses a circle definition into a List of Points
///
/// the definition of the element as whitespace seperated String[]
/// the parsed element as a List of Points
private List ParseCircle(string[] currentElement)
{
double x = 0;
double y = 0;
double r = 0;
for (int j = 0; j < currentElement.Length; j++)
{
if (currentElement[j].StartsWith("cx="))
{
x = Convert.ToDouble(ParseSingleSVGAttribute(currentElement[j]), CultureInfo.InvariantCulture);
}
else if (currentElement[j].StartsWith("cy="))
{
y = Convert.ToDouble(ParseSingleSVGAttribute(currentElement[j]), CultureInfo.InvariantCulture);
}
else if (currentElement[j].StartsWith("r="))
{
r = Convert.ToDouble(ParseSingleSVGAttribute(currentElement[j]), CultureInfo.InvariantCulture);
}
}
return SampleEllipse(x, y, r, r);
}
///
/// parses a ellipse definition into a List of Points
///
/// the definition of the element as whitespace seperated String[]
/// the parsed element as a List of Points
private List ParseEllipse(string[] currentElement)
{
double x = 0;
double y = 0;
double rx = 0;
double ry = 0;
for (int j = 0; j < currentElement.Length; j++)
{
if (currentElement[j].StartsWith("cx="))
{
x = Convert.ToDouble(ParseSingleSVGAttribute(currentElement[j]), CultureInfo.InvariantCulture);
}
else if (currentElement[j].StartsWith("cy="))
{
y = Convert.ToDouble(ParseSingleSVGAttribute(currentElement[j]), CultureInfo.InvariantCulture);
}
else if (currentElement[j].StartsWith("rx="))
{
rx = Convert.ToDouble(ParseSingleSVGAttribute(currentElement[j]), CultureInfo.InvariantCulture);
}
else if (currentElement[j].StartsWith("ry="))
{
ry = Convert.ToDouble(ParseSingleSVGAttribute(currentElement[j]), CultureInfo.InvariantCulture);
}
}
return SampleEllipse(x, y, rx, ry);
}
///
/// parses a line definition into a List of two Points
///
/// the definition of the element as whitespace seperated String[]
/// the parsed element as a List of Points
private List ParseLine(string[] currentElement)
{
double x1 = 0;
double y1 = 0;
double x2 = 0;
double y2 = 0;
for (int j = 0; j < currentElement.Length; j++)
{
if (currentElement[j].StartsWith("x1="))
{
x1 = Convert.ToDouble(ParseSingleSVGAttribute(currentElement[j]), CultureInfo.InvariantCulture);
}
else if (currentElement[j].StartsWith("y1="))
{
y1 = Convert.ToDouble(ParseSingleSVGAttribute(currentElement[j]), CultureInfo.InvariantCulture);
}
else if (currentElement[j].StartsWith("x2="))
{
x2 = Convert.ToDouble(ParseSingleSVGAttribute(currentElement[j]), CultureInfo.InvariantCulture);
}
else if (currentElement[j].StartsWith("y2="))
{
y2 = Convert.ToDouble(ParseSingleSVGAttribute(currentElement[j]), CultureInfo.InvariantCulture);
}
}
List line = new List();
line.Add(ScaleAndCreatePoint(x1, y1));
line.Add(ScaleAndCreatePoint(x2, y2));
return line;
}
///
/// parses a polyline definition into a List of Points
///
/// the definition of the element as whitespace seperated String[]
/// the parsed element as a List of Points
private List ParsePolyline(string[] currentElement)
{
String[] points = null;
for (int j = 0; j < currentElement.Length; j++)
{
if (currentElement[j].StartsWith("points="))
{
List pointDefs = new List();
pointDefs.Add(currentElement[j].Substring(8)); //parse first point coordinates by removing 'points="'
j++;
while (!currentElement[j].EndsWith("\""))
{
pointDefs.Add(currentElement[j]); //parse intermediate point coordinates
j++;
}
pointDefs.Add(currentElement[j].Trim('"')); //parse last point coordinates by removing '"'
points = pointDefs.ToArray();
}
}
List polyline = new List();
for (int k = 0; k < points.Length - 1; k += 2)
{
polyline.Add(ScaleAndCreatePoint(Convert.ToDouble(points[k], CultureInfo.InvariantCulture), Convert.ToDouble(points[k + 1], CultureInfo.InvariantCulture)));
}
return polyline;
}
///
/// parses a polygon definition into a List of Points
///
/// the definition of the element as whitespace seperated String[]
/// the parsed element as a List of Points
private List ParsePolygon(string[] currentElement)
{
String[] points = null;
for (int j = 0; j < currentElement.Length; j++)
{
if (currentElement[j].StartsWith("points="))
{
List pointDefs = new List();
pointDefs.Add(currentElement[j].Substring(8)); //parse first point coordinates by removing 'points="'
j++;
while (!currentElement[j].EndsWith("\""))
{
pointDefs.Add(currentElement[j]); //parse intermediate point coordinates
j++;
}
pointDefs.Add(currentElement[j].Trim('"')); //parse last point coordinates by removing '"'
points = pointDefs.ToArray();
}
}
List polygon = new List();
for (int k = 0; k < points.Length - 1; k += 2)
{
polygon.Add(ScaleAndCreatePoint(Convert.ToDouble(points[k], CultureInfo.InvariantCulture), Convert.ToDouble(points[k + 1], CultureInfo.InvariantCulture)));
}
polygon.Add(ScaleAndCreatePoint(Convert.ToDouble(points[0], CultureInfo.InvariantCulture), Convert.ToDouble(points[1], CultureInfo.InvariantCulture))); //close polygon
return polygon;
}
///
/// parses a path definition into a List of Points
///
/// the definition of the element as whitespace seperated String[]
/// the parsed element as a List of Points
private List ParsePath(string[] currentElement)
{
List pathElements = new List();
for (int j = 0; j < currentElement.Length; j++)
{
if (currentElement[j].StartsWith("d="))
{
pathElements.Add(currentElement[j].Substring(3)); //parse first path element by removing 'd="'
j++;
while (!currentElement[j].EndsWith("\""))
{
pathElements.Add(currentElement[j]); //parse intermediate path element
j++;
}
pathElements.Add(currentElement[j].Trim('"')); //parse last path element by removing '"'
}
}
NormalizePathDeclaration(pathElements); //expand path data to always explicitly have the command descriptor in front of the appropriate number of arguments and to seperate command descriptors, coordinates and other tokens always into seperate list elements (equivalent to seperation with spaces in the input file, but svg allows also for comma as a seperator, and for omitting seperators where possible without losing information (refer to svg grammer) to reduce file size
List element = new List();
List currentLine = new List();
double lastBezierControlPointX = 0;
double lastBezierControlPointY = 0;
double lastPositionX;
double lastPositionY;
double initialPositionX = -1;
double initialPositionY = -1;
bool newSubpath = true;
Tuple, double, double> valuesArc; //list of points, new values for: lastPositionX, lastPositionY
Tuple, double, double, double, double> valuesBezierCurve; //list of points, new values for: lastPositionX, lastPositionY, lastBezierControlPointX, lastBezierControlPointY
var valuesSinglePoint = Parse_M_L(pathElements); //new point, new values for: lastPositionX, lastPositionY
currentLine = new List();
currentLine.Add(valuesSinglePoint.Item1);
lastPositionX = valuesSinglePoint.Item2;
lastPositionY = valuesSinglePoint.Item3;
String currentToken;
while (!(pathElements.Count == 0))
{
if (newSubpath)
{
initialPositionX = lastPositionX; //update buffers for coordinates of first point of active subpath
initialPositionY = lastPositionY;
newSubpath = false;
}
currentToken = pathElements.First();
if (currentToken.Equals("M"))
{
element.Add(new InternalLine(currentLine)); //save current line
valuesSinglePoint = Parse_M_L(pathElements);
currentLine = new List(); //create new empty line
currentLine.Add(valuesSinglePoint.Item1); //add point to new line
lastPositionX = valuesSinglePoint.Item2; //save last point coordinates
lastPositionY = valuesSinglePoint.Item3; //save last point coordinates
}
else if (currentToken.Equals("m"))
{
element.Add(new InternalLine(currentLine)); //save current line
valuesSinglePoint = Parse_m_l(pathElements, lastPositionX, lastPositionY);
currentLine = new List(); //create new empty line
currentLine.Add(valuesSinglePoint.Item1); //add point to new line
lastPositionX = valuesSinglePoint.Item2; //save last point coordinates
lastPositionY = valuesSinglePoint.Item3; //save last point coordinates
}
else if (currentToken.Equals("Z") || currentToken.Equals("z"))
{
valuesSinglePoint = Parse_Z(pathElements, initialPositionX, initialPositionY); //method call only used for uniform program structure... only real effect of method is to consume one token
newSubpath = true;
currentLine.Add(valuesSinglePoint.Item1); //add point to old line
element.Add(new InternalLine(currentLine)); //save current line
currentLine = new List(); //create new empty line
currentLine.Add(valuesSinglePoint.Item1); //add point to new line
lastPositionX = valuesSinglePoint.Item2; //save last point coordinates
lastPositionY = valuesSinglePoint.Item3; //save last point coordinates
}
else if (currentToken.Equals("L"))
{
valuesSinglePoint = Parse_M_L(pathElements);
currentLine.Add(valuesSinglePoint.Item1); //add point to new line
lastPositionX = valuesSinglePoint.Item2; //save last point coordinates
lastPositionY = valuesSinglePoint.Item3; //save last point coordinates
}
else if (currentToken.Equals("l"))
{
valuesSinglePoint = Parse_m_l(pathElements, lastPositionX, lastPositionY);
currentLine.Add(valuesSinglePoint.Item1); //add point to new line
lastPositionX = valuesSinglePoint.Item2; //save last point coordinates
lastPositionY = valuesSinglePoint.Item3; //save last point coordinates
}
else if (currentToken.Equals("H"))
{
valuesSinglePoint = Parse_H(pathElements, lastPositionY);
currentLine.Add(valuesSinglePoint.Item1); //add point to new line
lastPositionX = valuesSinglePoint.Item2; //save last point coordinates
lastPositionY = valuesSinglePoint.Item3; //save last point coordinates
}
else if (currentToken.Equals("h"))
{
valuesSinglePoint = Parse_h(pathElements, lastPositionX, lastPositionY);
currentLine.Add(valuesSinglePoint.Item1); //add point to new line
lastPositionX = valuesSinglePoint.Item2; //save last point coordinates
lastPositionY = valuesSinglePoint.Item3; //save last point coordinates
}
else if (currentToken.Equals("V"))
{
valuesSinglePoint = Parse_V(pathElements, lastPositionX);
currentLine.Add(valuesSinglePoint.Item1); //add point to new line
lastPositionX = valuesSinglePoint.Item2; //save last point coordinates
lastPositionY = valuesSinglePoint.Item3; //save last point coordinates
}
else if (currentToken.Equals("v"))
{
valuesSinglePoint = Parse_v(pathElements, lastPositionX, lastPositionY);
currentLine.Add(valuesSinglePoint.Item1); //add point to new line
lastPositionX = valuesSinglePoint.Item2; //save last point coordinates
lastPositionY = valuesSinglePoint.Item3; //save last point coordinates
}
else if (currentToken.Equals("C"))
{
valuesBezierCurve = Parse_C(pathElements, lastPositionX, lastPositionY);
currentLine.AddRange(valuesBezierCurve.Item1); //add point to new line
lastPositionX = valuesBezierCurve.Item2; //save last point coordinates
lastPositionY = valuesBezierCurve.Item3; //save last point coordinates
lastBezierControlPointX = valuesBezierCurve.Item4; //save last bezier control point coordinates
lastBezierControlPointY = valuesBezierCurve.Item5; //save last bezier control point coordinates
}
else if (currentToken.Equals("c"))
{
valuesBezierCurve = Parse_C(pathElements, lastPositionX, lastPositionY);
currentLine.AddRange(valuesBezierCurve.Item1); //add point to new line
lastPositionX = valuesBezierCurve.Item2; //save last point coordinates
lastPositionY = valuesBezierCurve.Item3; //save last point coordinates
lastBezierControlPointX = valuesBezierCurve.Item4; //save last bezier control point coordinates
lastBezierControlPointY = valuesBezierCurve.Item5; //save last bezier control point coordinates
}
else if (currentToken.Equals("S"))
{
valuesBezierCurve = Parse_S(pathElements, lastPositionX, lastPositionY, lastBezierControlPointX, lastBezierControlPointY);
currentLine.AddRange(valuesBezierCurve.Item1); //add point to new line
lastPositionX = valuesBezierCurve.Item2; //save last point coordinates
lastPositionY = valuesBezierCurve.Item3; //save last point coordinates
lastBezierControlPointX = valuesBezierCurve.Item4; //save last bezier control point coordinates
lastBezierControlPointY = valuesBezierCurve.Item5; //save last bezier control point coordinates
}
else if (currentToken.Equals("s"))
{
valuesBezierCurve = Parse_s(pathElements, lastPositionX, lastPositionY, lastBezierControlPointX, lastBezierControlPointY);
currentLine.AddRange(valuesBezierCurve.Item1); //add point to new line
lastPositionX = valuesBezierCurve.Item2; //save last point coordinates
lastPositionY = valuesBezierCurve.Item3; //save last point coordinates
lastBezierControlPointX = valuesBezierCurve.Item4; //save last bezier control point coordinates
lastBezierControlPointY = valuesBezierCurve.Item5; //save last bezier control point coordinates
}
else if (currentToken.Equals("Q"))
{
valuesBezierCurve = Parse_Q(pathElements, lastPositionX, lastPositionY);
currentLine.AddRange(valuesBezierCurve.Item1); //add point to new line
lastPositionX = valuesBezierCurve.Item2; //save last point coordinates
lastPositionY = valuesBezierCurve.Item3; //save last point coordinates
lastBezierControlPointX = valuesBezierCurve.Item4; //save last bezier control point coordinates
lastBezierControlPointY = valuesBezierCurve.Item5; //save last bezier control point coordinates
}
else if (currentToken.Equals("q"))
{
valuesBezierCurve = Parse_q(pathElements, lastPositionX, lastPositionY);
currentLine.AddRange(valuesBezierCurve.Item1); //add point to new line
lastPositionX = valuesBezierCurve.Item2; //save last point coordinates
lastPositionY = valuesBezierCurve.Item3; //save last point coordinates
lastBezierControlPointX = valuesBezierCurve.Item4; //save last bezier control point coordinates
lastBezierControlPointY = valuesBezierCurve.Item5; //save last bezier control point coordinates
}
else if (currentToken.Equals("T"))
{
valuesBezierCurve = Parse_T(pathElements, lastPositionX, lastPositionY, lastBezierControlPointX, lastBezierControlPointY);
currentLine.AddRange(valuesBezierCurve.Item1); //add point to new line
lastPositionX = valuesBezierCurve.Item2; //save last point coordinates
lastPositionY = valuesBezierCurve.Item3; //save last point coordinates
lastBezierControlPointX = valuesBezierCurve.Item4; //save last bezier control point coordinates
lastBezierControlPointY = valuesBezierCurve.Item5; //save last bezier control point coordinates
}
else if (currentToken.Equals("t"))
{
valuesBezierCurve = Parse_t(pathElements, lastPositionX, lastPositionY, lastBezierControlPointX, lastBezierControlPointY);
currentLine.AddRange(valuesBezierCurve.Item1); //add point to new line
lastPositionX = valuesBezierCurve.Item2; //save last point coordinates
lastPositionY = valuesBezierCurve.Item3; //save last point coordinates
lastBezierControlPointX = valuesBezierCurve.Item4; //save last bezier control point coordinates
lastBezierControlPointY = valuesBezierCurve.Item5; //save last bezier control point coordinates
}
else if (currentToken.Equals("A"))
{
valuesArc = Parse_A(pathElements, lastPositionX, lastPositionY);
currentLine.AddRange(valuesArc.Item1); //add points to new line
lastPositionX = valuesArc.Item2; //save last point coordinates
lastPositionY = valuesArc.Item3; //save last point coordinates
}
else if (currentToken.Equals("a"))
{
valuesArc = Parse_a(pathElements, lastPositionX, lastPositionY);
currentLine.AddRange(valuesArc.Item1); //add points to new line
lastPositionX = valuesArc.Item2; //save last point coordinates
lastPositionY = valuesArc.Item3; //save last point coordinates
}
else
{
throw new FileImporterException("invalid path argument or path data formatting: read argument " + pathElements.First(), "valid path arguments are: {M,Z,L,H,V,C,S,Q,T,A} in upper and lower case", i + 1);
}
}
if (currentLine.Count > 1)
{
element.Add(new InternalLine(currentLine)); //save current line
}
return element;
}
///
/// normalizes the declaration of the data field of a path declaration by splitting coordinates still connected by a semicolon and command descriptors which are directly attached to the following coordinate into seperate tokens, also repeats omitted command descriptor tokens when the same command is repeated multiple times
///
/// the list of tokens to normalize, by splitting up existing tokens and adding new command descriptor tokens
private void NormalizePathDeclaration(List pathElements)
{
Char lastCommand = 'M';
int argumentCounter = 0;
for (int j = 0; j < pathElements.Count; j++)
{
String currentElement = pathElements.ElementAt(j);
if (currentElement.Length != 1)
{
if (((currentElement.First() >= 'A' && currentElement.First() <= 'Z') || (currentElement.First() >= 'a' && currentElement.First() <= 'z')) && currentElement.First() != 'e') //seperate a single command descriptor / letter
{
pathElements.RemoveAt(j);
pathElements.Insert(j, currentElement.First() + ""); //insert letter as seperate element
pathElements.Insert(j + 1, currentElement.Substring(1)); //insert rest of String at next position so it will be processed again
lastCommand = currentElement.First();
argumentCounter = 0;
}
else if ((currentElement.First() >= '0' && currentElement.First() <= '9') || currentElement.First() == '-' || currentElement.First() == '+' || currentElement.First() != 'e') //seperate a single coordinate / number
{
bool repeatCommandDescriptor = false;
switch (lastCommand)
{ //check for reaching of next command with omitted command descriptor
case 'M':
if (argumentCounter >= 2) repeatCommandDescriptor = true;
break;
case 'm':
if (argumentCounter >= 2) repeatCommandDescriptor = true;
break;
case 'L':
if (argumentCounter >= 2) repeatCommandDescriptor = true;
break;
case 'l':
if (argumentCounter >= 2) repeatCommandDescriptor = true;
break;
case 'V':
if (argumentCounter >= 1) repeatCommandDescriptor = true;
break;
case 'v':
if (argumentCounter >= 1) repeatCommandDescriptor = true;
break;
case 'H':
if (argumentCounter >= 1) repeatCommandDescriptor = true;
break;
case 'h':
if (argumentCounter >= 1) repeatCommandDescriptor = true;
break;
case 'C':
if (argumentCounter >= 6) repeatCommandDescriptor = true;
break;
case 'c':
if (argumentCounter >= 6) repeatCommandDescriptor = true;
break;
case 'S':
if (argumentCounter >= 4) repeatCommandDescriptor = true;
break;
case 's':
if (argumentCounter >= 4) repeatCommandDescriptor = true;
break;
case 'Q':
if (argumentCounter >= 4) repeatCommandDescriptor = true;
break;
case 'q':
if (argumentCounter >= 4) repeatCommandDescriptor = true;
break;
case 'T':
if (argumentCounter >= 2) repeatCommandDescriptor = true;
break;
case 't':
if (argumentCounter >= 2) repeatCommandDescriptor = true;
break;
case 'A':
if (argumentCounter >= 7) repeatCommandDescriptor = true;
break;
case 'a':
if (argumentCounter >= 7) repeatCommandDescriptor = true;
break;
}
if (repeatCommandDescriptor)
{
pathElements.Insert(j, lastCommand + ""); //repeat command descriptor
j++; //skip command descriptor (was put into active position in the list
argumentCounter = 0; //reset argument counter
}
bool decimalPointEncountered = false;
for (int k = 1; k < currentElement.Length; k++)
{
if (!decimalPointEncountered && currentElement.ElementAt(k) == '.') //allow up to one decimal point in numbers
{
decimalPointEncountered = true;
}
else if (!((currentElement.ElementAt(k) >= '0' && currentElement.ElementAt(k) <= '9') || currentElement.First() == '-' || currentElement.First() == '+' || currentElement.First() != 'e'))
{
pathElements.RemoveAt(j);
pathElements.Insert(j, currentElement.Substring(0, k - 1)); //insert number as seperate element
pathElements.Insert(j + 1, currentElement.Substring(k)); //insert rest of String at next position so it will be processed again
break;
}
}
argumentCounter++;
}
else //parse non-space seperators and skip other unsupported characters (the only other valid ones per svg standard would be weird tokens looking like format descriptors (e.g. '#xC'), these are unsopported and will likely cause an error or other inconsitencies during parsing)
{
for (int k = 1; k < currentElement.Length; k++)
{
if (((currentElement.ElementAt(k) >= '0' && currentElement.ElementAt(k) <= '9')) || currentElement.ElementAt(k) == '-' || currentElement.ElementAt(k) == '+' || (currentElement.ElementAt(k) >= 'A' && currentElement.ElementAt(k) <= 'Z') || (currentElement.ElementAt(k) >= 'a' && currentElement.ElementAt(k) <= 'z'))
{
pathElements.RemoveAt(j);
pathElements.Insert(j + 1, currentElement.Substring(k)); //insert rest of String at next position so it will be processed again
break;
}
}
}
}
else
{
if ((currentElement.First() >= 'A' && currentElement.First() <= 'Z') || (currentElement.First() >= 'a' && currentElement.First() <= 'z')) //update lastCommand buffer when reading single letter
{
lastCommand = currentElement.First();
argumentCounter = 0;
}
else if (!(currentElement.First() >= '0' && currentElement.First() <= '9')) //not a number
{
pathElements.RemoveAt(j); //remove element
j--; //decrement index pointer so next element will not be skipped (indices of all folowing elements just decreased by 1)
}
else //a single digit number
{
bool repeatCommandDescriptor = false;
switch (lastCommand)
{ //check for reaching of next command with omitted command descriptor
case 'M':
if (argumentCounter >= 2) repeatCommandDescriptor = true;
break;
case 'm':
if (argumentCounter >= 2) repeatCommandDescriptor = true;
break;
case 'L':
if (argumentCounter >= 2) repeatCommandDescriptor = true;
break;
case 'l':
if (argumentCounter >= 2) repeatCommandDescriptor = true;
break;
case 'V':
if (argumentCounter >= 1) repeatCommandDescriptor = true;
break;
case 'v':
if (argumentCounter >= 1) repeatCommandDescriptor = true;
break;
case 'H':
if (argumentCounter >= 1) repeatCommandDescriptor = true;
break;
case 'h':
if (argumentCounter >= 1) repeatCommandDescriptor = true;
break;
case 'C':
if (argumentCounter >= 6) repeatCommandDescriptor = true;
break;
case 'c':
if (argumentCounter >= 6) repeatCommandDescriptor = true;
break;
case 'S':
if (argumentCounter >= 4) repeatCommandDescriptor = true;
break;
case 's':
if (argumentCounter >= 4) repeatCommandDescriptor = true;
break;
case 'Q':
if (argumentCounter >= 4) repeatCommandDescriptor = true;
break;
case 'q':
if (argumentCounter >= 4) repeatCommandDescriptor = true;
break;
case 'T':
if (argumentCounter >= 2) repeatCommandDescriptor = true;
break;
case 't':
if (argumentCounter >= 2) repeatCommandDescriptor = true;
break;
case 'A':
if (argumentCounter >= 7) repeatCommandDescriptor = true;
break;
case 'a':
if (argumentCounter >= 7) repeatCommandDescriptor = true;
break;
}
if (repeatCommandDescriptor)
{
pathElements.Insert(j, lastCommand + ""); //repeat command descriptor
j++; //skip command descriptor (was put into active position in the list
argumentCounter = 0; //reset argument counter
}
argumentCounter++;
}
}
}
}
///
/// parses a "closeloop" path element
///
/// a list of all not yet parsed path element tokens and values in correct order, starting with the element to be parsed
/// absolute x coordinate of the last initial point of this subpath
/// absolute y coordinate of the last initial point of this subpath
///
private Tuple Parse_Z(List pathElements, double initialPositionX, double initialPositionY)
{
pathElements.RemoveAt(0); //remove element descriptor token
return new Tuple(ScaleAndCreatePoint(initialPositionX, initialPositionY), initialPositionX, initialPositionY);
}
///
/// parses a "moveto", "close loop" or "lineto" path element with absolute coordinates
///
/// a list of all not yet parsed path element tokens and values in correct order, starting with the element to be parsed
/// the point at the end of the move, close loop or line action and its exact, unscaled coordinates
private Tuple Parse_M_L(List pathElements)
{
pathElements.RemoveAt(0); //remove element descriptor token
double x = Convert.ToDouble(pathElements.First(), CultureInfo.InvariantCulture); //parse x coordinate
pathElements.RemoveAt(0); //remove x coordinate token
double y = Convert.ToDouble(pathElements.First(), CultureInfo.InvariantCulture); //parse y coordinate
pathElements.RemoveAt(0); //remove y coordinate token
return new Tuple(ScaleAndCreatePoint(x, y), x, y);
}
///
/// parses a "moveto", "close loop" or "lineto" path element with relative coordinates
///
/// a list of all not yet parsed path element tokens and values in correct order, starting with the element to be parsed
/// absolute x coordinate of the last active point
/// absolute y coordinate of the last active point
/// the point at the end of the move, close loop or line action and its exact, unscaled coordinates
private Tuple Parse_m_l(List pathElements, double lastPositionX, double lastPositionY)
{
pathElements.RemoveAt(0); //remove element descriptor token
double x = Convert.ToDouble(pathElements.First(), CultureInfo.InvariantCulture); //parse relative x coordinate
pathElements.RemoveAt(0); //remove x coordinate token
double y = Convert.ToDouble(pathElements.First(), CultureInfo.InvariantCulture); //parse relative y coordinate
pathElements.RemoveAt(0); //remove y coordinate token
x = lastPositionX + x; //compute absolute x coordinate
y = lastPositionY + y; //compute absolute y coordinate
return new Tuple(ScaleAndCreatePoint(x, y), x, y);
}
///
/// parses a "horizontal lineto" path element with absolute coordinates
///
/// a list of all not yet parsed path element tokens and values in correct order, starting with the element to be parsed
/// absolute y coordinate of the last active point
/// the point at the end of the horizontal line action and its exact, unscaled coordinates
private Tuple Parse_H(List pathElements, double lastPositionY)
{
pathElements.RemoveAt(0); //remove element descriptor token
double x = Convert.ToDouble(pathElements.First(), CultureInfo.InvariantCulture); //parse x coordinate
pathElements.RemoveAt(0); //remove x coordinate token
return new Tuple(ScaleAndCreatePoint(x, lastPositionY), x, lastPositionY);
}
///
/// parses a "horizontal lineto" path element with relative coordinates
///
/// a list of all not yet parsed path element tokens and values in correct order, starting with the element to be parsed
/// absolute x coordinate of the last active point
/// absolute y coordinate of the last active point
/// the point at the end of the horizontal line action and its exact, unscaled coordinates
private Tuple Parse_h(List pathElements, double lastPositionX, double lastPositionY)
{
pathElements.RemoveAt(0); //remove element descriptor token
double x = Convert.ToDouble(pathElements.First(), CultureInfo.InvariantCulture); //parse relative x coordinate
pathElements.RemoveAt(0); //remove x coordinate token
x = lastPositionX + x; //compute absolute x coordinate
return new Tuple(ScaleAndCreatePoint(x, lastPositionY), x, lastPositionY);
}
///
/// parses a "vertical lineto" path element with absolute coordinates
///
/// a list of all not yet parsed path element tokens and values in correct order, starting with the element to be parsed
/// absolute x coordinate of the last active point
/// the point at the end of the vertical line action and its exact, unscaled coordinates
private Tuple Parse_V(List pathElements, double lastPositionX)
{
pathElements.RemoveAt(0); //remove element descriptor token
double y = Convert.ToDouble(pathElements.First(), CultureInfo.InvariantCulture); //parse y coordinate
pathElements.RemoveAt(0); //remove y coordinate token
return new Tuple(ScaleAndCreatePoint(lastPositionX, y), lastPositionX, y);
}
///
/// parses a "vertical lineto" path element with relative coordinates
///
/// a list of all not yet parsed path element tokens and values in correct order, starting with the element to be parsed
/// absolute x coordinate of the last active point
/// absolute y coordinate of the last active point
/// the point at the end of the vertical line action and its exact, unscaled coordinates
private Tuple Parse_v(List pathElements, double lastPositionX, double lastPositionY)
{
pathElements.RemoveAt(0); //remove element descriptor token
double y = Convert.ToDouble(pathElements.First(), CultureInfo.InvariantCulture); //parse relative y coordinate
pathElements.RemoveAt(0); //remove y coordinate token
y = lastPositionY + y; //compute absolute y coordinate
return new Tuple(ScaleAndCreatePoint(lastPositionX, y), lastPositionX, y);
}
///
/// parses a "cubic bezier curve" path element with absolute coordinates
///
/// a list of all not yet parsed path element tokens and values in correct order, starting with the element to be parsed
/// absolute x coordinate of the last active point
/// absolute y coordinate of the last active point
/// a List of Points containing all sampled points on the bezier curve, aswell as the unscaled x and y coordinates of the last point of the curve and of the second bezier control point
private Tuple, double, double, double, double> Parse_C(List pathElements, double lastPositionX, double lastPositionY)
{
pathElements.RemoveAt(0); //remove element descriptor token
double x1 = Convert.ToDouble(pathElements.First(), CultureInfo.InvariantCulture); //parse first control point x coordinate
pathElements.RemoveAt(0); //remove x coordinate token
double y1 = Convert.ToDouble(pathElements.First(), CultureInfo.InvariantCulture); //parse first control point y coordinate
pathElements.RemoveAt(0); //remove y coordinate token
double x2 = Convert.ToDouble(pathElements.First(), CultureInfo.InvariantCulture); //parse second control point x coordinate
pathElements.RemoveAt(0); //remove x coordinate token
double y2 = Convert.ToDouble(pathElements.First(), CultureInfo.InvariantCulture); //parse second control point y coordinate
pathElements.RemoveAt(0); //remove y coordinate token
double x = Convert.ToDouble(pathElements.First(), CultureInfo.InvariantCulture); //parse target point x coordinate
pathElements.RemoveAt(0); //remove x coordinate token
double y = Convert.ToDouble(pathElements.First(), CultureInfo.InvariantCulture); //parse target point y coordinate
pathElements.RemoveAt(0); //remove y coordinate token
return new Tuple, double, double, double, double>(SampleCubicBezier(lastPositionX, lastPositionY, x1, y1, x2, y2, x, y), x, y, x2, y2);
}
///
/// parses a "cubic bezier curve" path element with relative coordinates
///
/// a list of all not yet parsed path element tokens and values in correct order, starting with the element to be parsed
/// absolute x coordinate of the last active point
/// absolute y coordinate of the last active point
/// a List of Points containing all sampled points on the bezier curve, aswell as the unscaled x and y coordinates of the last point of the curve and of the second bezier control point
private Tuple, double, double, double, double> Parse_c(List pathElements, double lastPositionX, double lastPositionY)
{
pathElements.RemoveAt(0); //remove element descriptor token
double x1 = Convert.ToDouble(pathElements.First(), CultureInfo.InvariantCulture); //parse first control point x coordinate
pathElements.RemoveAt(0); //remove x coordinate token
double y1 = Convert.ToDouble(pathElements.First(), CultureInfo.InvariantCulture); //parse first control point y coordinate
pathElements.RemoveAt(0); //remove y coordinate token
double x2 = Convert.ToDouble(pathElements.First(), CultureInfo.InvariantCulture); //parse second control point x coordinate
pathElements.RemoveAt(0); //remove x coordinate token
double y2 = Convert.ToDouble(pathElements.First(), CultureInfo.InvariantCulture); //parse second control point y coordinate
pathElements.RemoveAt(0); //remove y coordinate token
double x = Convert.ToDouble(pathElements.First(), CultureInfo.InvariantCulture); //parse target point x coordinate
pathElements.RemoveAt(0); //remove x coordinate token
double y = Convert.ToDouble(pathElements.First(), CultureInfo.InvariantCulture); //parse target point y coordinate
pathElements.RemoveAt(0); //remove y coordinate token
x1 = lastPositionX + x1; //compute absolute x coordinate
y1 = lastPositionY + y1; //compute absolute y coordinate
x2 = lastPositionX + x2; //compute absolute x coordinate
y2 = lastPositionY + y2; //compute absolute y coordinate
x = lastPositionX + x; //compute absolute x coordinate
y = lastPositionY + y; //compute absolute y coordinate
return new Tuple, double, double, double, double>(SampleCubicBezier(lastPositionX, lastPositionY, x1, y1, x2, y2, x, y), x, y, x2, y2);
}
///
/// parses a "cubic bezier curve shorthand" path element with absolute coordinates
///
/// a list of all not yet parsed path element tokens and values in correct order, starting with the element to be parsed
/// absolute x coordinate of the last active point
/// absolute y coordinate of the last active point
/// absolute x coordinate of the last bezier control point of the previous bezier curve
/// absolute y coordinate of the last bezier control point of the previous bezier curve
/// a List of Points containing all sampled points on the bezier curve, aswell as the unscaled x and y coordinates of the last point of the curve and of the second bezier control point
private Tuple, double, double, double, double> Parse_S(List pathElements, double lastPositionX, double lastPositionY, double lastBezierControlPointX, double lastBezierControlPointY)
{
pathElements.RemoveAt(0); //remove element descriptor token
double x2 = Convert.ToDouble(pathElements.First(), CultureInfo.InvariantCulture); //parse second control point x coordinate
pathElements.RemoveAt(0); //remove x coordinate token
double y2 = Convert.ToDouble(pathElements.First(), CultureInfo.InvariantCulture); //parse second control point y coordinate
pathElements.RemoveAt(0); //remove y coordinate token
double x = Convert.ToDouble(pathElements.First(), CultureInfo.InvariantCulture); //parse target point x coordinate
pathElements.RemoveAt(0); //remove x coordinate token
double y = Convert.ToDouble(pathElements.First(), CultureInfo.InvariantCulture); //parse target point y coordinate
pathElements.RemoveAt(0); //remove y coordinate token
double x1 = lastPositionX + (lastPositionX - lastBezierControlPointX); //mirror last bezier control point at bezier start point to get first new bezier control point
double y1 = lastPositionY + (lastPositionY - lastBezierControlPointY); //mirror last bezier control point at bezier start point to get first new bezier control point
return new Tuple, double, double, double, double>(SampleCubicBezier(lastPositionX, lastPositionY, x1, y1, x2, y2, x, y), x, y, x2, y2);
}
///
/// parses a "cubic bezier curve shorthand" path element with relative coordinates
///
/// a list of all not yet parsed path element tokens and values in correct order, starting with the element to be parsed
/// absolute x coordinate of the last active point
/// absolute y coordinate of the last active point
/// absolute x coordinate of the last bezier control point of the previous bezier curve
/// absolute y coordinate of the last bezier control point of the previous bezier curve
/// a List of Points containing all sampled points on the bezier curve, aswell as the unscaled x and y coordinates of the last point of the curve and of the second bezier control point
private Tuple, double, double, double, double> Parse_s(List pathElements, double lastPositionX, double lastPositionY, double lastBezierControlPointX, double lastBezierControlPointY)
{
pathElements.RemoveAt(0); //remove element descriptor token
double x2 = Convert.ToDouble(pathElements.First(), CultureInfo.InvariantCulture); //parse second control point x coordinate
pathElements.RemoveAt(0); //remove x coordinate token
double y2 = Convert.ToDouble(pathElements.First(), CultureInfo.InvariantCulture); //parse second control point y coordinate
pathElements.RemoveAt(0); //remove y coordinate token
double x = Convert.ToDouble(pathElements.First(), CultureInfo.InvariantCulture); //parse target point x coordinate
pathElements.RemoveAt(0); //remove x coordinate token
double y = Convert.ToDouble(pathElements.First(), CultureInfo.InvariantCulture); //parse target point y coordinate
pathElements.RemoveAt(0); //remove y coordinate token
double x1 = lastPositionX + (lastPositionX - lastBezierControlPointX); //mirror last bezier control point at bezier start point to get first new bezier control point
double y1 = lastPositionY + (lastPositionY - lastBezierControlPointY); //mirror last bezier control point at bezier start point to get first new bezier control point
x2 = lastPositionX + x2; //compute absolute x coordinate
y2 = lastPositionY + y2; //compute absolute y coordinate
x = lastPositionX + x; //compute absolute x coordinate
y = lastPositionY + y; //compute absolute y coordinate
return new Tuple, double, double, double, double>(SampleCubicBezier(lastPositionX, lastPositionY, x1, y1, x2, y2, x, y), x, y, x2, y2);
}
///
/// parses a "quadratic bezier curve" path element with absolute coordinates
///
/// a list of all not yet parsed path element tokens and values in correct order, starting with the element to be parsed
/// absolute x coordinate of the last active point
/// absolute y coordinate of the last active point
/// a List of Points containing all sampled points on the bezier curve, aswell as the unscaled x and y coordinates of the last point of the curve and of the bezier control point
private Tuple, double, double, double, double> Parse_Q(List pathElements, double lastPositionX, double lastPositionY)
{
pathElements.RemoveAt(0); //remove element descriptor token
double x1 = Convert.ToDouble(pathElements.First(), CultureInfo.InvariantCulture); //parse control point x coordinate
pathElements.RemoveAt(0); //remove x coordinate token
double y1 = Convert.ToDouble(pathElements.First(), CultureInfo.InvariantCulture); //parse control point y coordinate
pathElements.RemoveAt(0); //remove y coordinate token
double x = Convert.ToDouble(pathElements.First(), CultureInfo.InvariantCulture); //parse target point x coordinate
pathElements.RemoveAt(0); //remove x coordinate token
double y = Convert.ToDouble(pathElements.First(), CultureInfo.InvariantCulture); //parse target point y coordinate
pathElements.RemoveAt(0); //remove y coordinate token
return new Tuple, double, double, double, double>(SampleQuadraticBezier(lastPositionX, lastPositionY, x1, y1, x, y), x, y, x1, y1);
}
///
/// parses a "quadratic bezier curve" path element with relative coordinates
///
/// a list of all not yet parsed path element tokens and values in correct order, starting with the element to be parsed
/// absolute x coordinate of the last active point
/// absolute y coordinate of the last active point
/// a List of Points containing all sampled points on the bezier curve, aswell as the unscaled x and y coordinates of the last point of the curve and of the bezier control point
private Tuple, double, double, double, double> Parse_q(List pathElements, double lastPositionX, double lastPositionY)
{
pathElements.RemoveAt(0); //remove element descriptor token
double x1 = Convert.ToDouble(pathElements.First(), CultureInfo.InvariantCulture); //parse control point x coordinate
pathElements.RemoveAt(0); //remove x coordinate token
double y1 = Convert.ToDouble(pathElements.First(), CultureInfo.InvariantCulture); //parse control point y coordinate
pathElements.RemoveAt(0); //remove y coordinate token
double x = Convert.ToDouble(pathElements.First(), CultureInfo.InvariantCulture); //parse target point x coordinate
pathElements.RemoveAt(0); //remove x coordinate token
double y = Convert.ToDouble(pathElements.First(), CultureInfo.InvariantCulture); //parse target point y coordinate
pathElements.RemoveAt(0); //remove y coordinate token
x1 = lastPositionX + x1; //compute absolute x coordinate
y1 = lastPositionY + y1; //compute absolute y coordinate
x = lastPositionX + x; //compute absolute x coordinate
y = lastPositionY + y; //compute absolute y coordinate
return new Tuple, double, double, double, double>(SampleQuadraticBezier(lastPositionX, lastPositionY, x1, y1, x, y), x, y, x1, y1);
}
///
/// parses a "quadratic bezier curve shorthand" path element with absolute coordinates
///
/// a list of all not yet parsed path element tokens and values in correct order, starting with the element to be parsed
/// absolute x coordinate of the last active point
/// absolute y coordinate of the last active point
/// absolute x coordinate of the last bezier control point of the previous bezier curve
/// absolute y coordinate of the last bezier control point of the previous bezier curve
/// a List of Points containing all sampled points on the bezier curve, aswell as the unscaled x and y coordinates of the last point of the curve and of the bezier control point
private Tuple, double, double, double, double> Parse_T(List pathElements, double lastPositionX, double lastPositionY, double lastBezierControlPointX, double lastBezierControlPointY)
{
pathElements.RemoveAt(0); //remove element descriptor token
double x = Convert.ToDouble(pathElements.First(), CultureInfo.InvariantCulture); //parse target point x coordinate
pathElements.RemoveAt(0); //remove x coordinate token
double y = Convert.ToDouble(pathElements.First(), CultureInfo.InvariantCulture); //parse target point y coordinate
pathElements.RemoveAt(0); //remove y coordinate token
double x1 = lastPositionX + (lastPositionX - lastBezierControlPointX); //mirror last bezier control point at bezier start point to get first new bezier control point
double y1 = lastPositionY + (lastPositionY - lastBezierControlPointY); //mirror last bezier control point at bezier start point to get first new bezier control point
return new Tuple, double, double, double, double>(SampleQuadraticBezier(lastPositionX, lastPositionY, x1, y1, x, y), x, y, x1, y1);
}
///
/// parses a "quadratic bezier curve shorthand" path element with relative coordinates
///
/// a list of all not yet parsed path element tokens and values in correct order, starting with the element to be parsed
/// absolute x coordinate of the last active point
/// absolute y coordinate of the last active point
/// absolute x coordinate of the last bezier control point of the previous bezier curve
/// absolute y coordinate of the last bezier control point of the previous bezier curve
/// a List of Points containing all sampled points on the bezier curve, aswell as the unscaled x and y coordinates of the last point of the curve and of the bezier control point
private Tuple, double, double, double, double> Parse_t(List pathElements, double lastPositionX, double lastPositionY, double lastBezierControlPointX, double lastBezierControlPointY)
{
pathElements.RemoveAt(0); //remove element descriptor token
double x = Convert.ToDouble(pathElements.First(), CultureInfo.InvariantCulture); //parse target point x coordinate
pathElements.RemoveAt(0); //remove x coordinate token
double y = Convert.ToDouble(pathElements.First(), CultureInfo.InvariantCulture); //parse target point y coordinate
pathElements.RemoveAt(0); //remove y coordinate token
x = lastPositionX + x; //compute absolute x coordinate
y = lastPositionY + y; //compute absolute y coordinate
double x1 = lastPositionX + (lastPositionX - lastBezierControlPointX); //mirror last bezier control point at bezier start point to get first new bezier control point
double y1 = lastPositionY + (lastPositionY - lastBezierControlPointY); //mirror last bezier control point at bezier start point to get first new bezier control point
return new Tuple, double, double, double, double>(SampleQuadraticBezier(lastPositionX, lastPositionY, x1, y1, x, y), x, y, x1, y1);
}
///
/// parses a "elliptical arc" path element with absolute coordinates
///
/// a list of all not yet parsed path element tokens and values in correct order, starting with the element to be parsed
/// absolute x coordinate of the last active point
/// absolute y coordinate of the last active point
/// a List of Points containing all sampled points on the elliptic arc, aswell as the unscaled x and y coordinates of the last point of the arc
private Tuple, double, double> Parse_A(List pathElements, double lastPositionX, double lastPositionY)
{
pathElements.RemoveAt(0); //remove element descriptor token
double rx = Convert.ToDouble(pathElements.First(), CultureInfo.InvariantCulture); //parse x radius
pathElements.RemoveAt(0); //remove x radius token
double ry = Convert.ToDouble(pathElements.First(), CultureInfo.InvariantCulture); //parse y radius
pathElements.RemoveAt(0); //remove y radius token
double thetha = Convert.ToDouble(pathElements.First(), CultureInfo.InvariantCulture); //parse rotation
pathElements.RemoveAt(0); //remove rotation token
bool largeArcFlag = Convert.ToInt16(pathElements.First()) == 1 ? true : false; //parse large arc flag
pathElements.RemoveAt(0); //remove large arc flag token
bool sweepFlag = Convert.ToInt16(pathElements.First()) == 1 ? true : false; //parse sweep flag
pathElements.RemoveAt(0); //remove sweep flag token
double x = Convert.ToDouble(pathElements.First(), CultureInfo.InvariantCulture); //parse target point x coordinate
pathElements.RemoveAt(0); //remove x coordinate token
double y = Convert.ToDouble(pathElements.First(), CultureInfo.InvariantCulture); //parse target point y coordinate
pathElements.RemoveAt(0); //remove y coordinate token
x = x - lastPositionX; //compute relative x coordinate
y = y - lastPositionY; //compute relative y coordinate
return new Tuple, double, double>(SampleArc(lastPositionX, lastPositionY, rx, ry, x, y, thetha, largeArcFlag, sweepFlag), x, y);
}
///
/// parses a "elliptical arc" path element with relative coordinates
///
/// a list of all not yet parsed path element tokens and values in correct order, starting with the element to be parsed
/// absolute x coordinate of the last active point
/// absolute y coordinate of the last active point
/// a List of Points containing all sampled points on the elliptic arc, aswell as the unscaled x and y coordinates of the last point of the arc
private Tuple, double, double> Parse_a(List pathElements, double lastPositionX, double lastPositionY)
{
pathElements.RemoveAt(0); //remove element descriptor token
double rx = Convert.ToDouble(pathElements.First(), CultureInfo.InvariantCulture); //parse x radius
pathElements.RemoveAt(0); //remove x radius token
double ry = Convert.ToDouble(pathElements.First(), CultureInfo.InvariantCulture); //parse y radius
pathElements.RemoveAt(0); //remove y radius token
double thetha = Convert.ToDouble(pathElements.First(), CultureInfo.InvariantCulture); //parse rotation
pathElements.RemoveAt(0); //remove rotation token
bool largeArcFlag = Convert.ToInt16(pathElements.First()) == 1 ? true : false; //parse large arc flag
pathElements.RemoveAt(0); //remove large arc flag token
bool sweepFlag = Convert.ToInt16(pathElements.First()) == 1 ? true : false; //parse sweep flag
pathElements.RemoveAt(0); //remove sweep flag token
double x = Convert.ToDouble(pathElements.First(), CultureInfo.InvariantCulture); //parse target point x coordinate
pathElements.RemoveAt(0); //remove x coordinate token
double y = Convert.ToDouble(pathElements.First(), CultureInfo.InvariantCulture); //parse target point y coordinate
pathElements.RemoveAt(0); //remove y coordinate token
return new Tuple, double, double>(SampleArc(lastPositionX, lastPositionY, rx, ry, x, y, thetha, largeArcFlag, sweepFlag), x, y);
}
///
/// samples an arc of an ellipse into a list of points
///
/// x coordinate of last point
/// y coordinate of last point
/// x radius of the ellipse
/// y radius of the ellipse
/// x coordinate of next point
/// y coordinate of next point
/// rotation of the ellipse around the x axis
/// flag determining if the large or the small arc is to be drawn
/// flag determining in which direction the arc is to be drawn (false = ccw, true = cw)
///
private List SampleArc(double lastPositionX, double lastPositionY, double rx, double ry, double nextPositionXRelative, double nextPositionYRelative, double thetha, bool largeArcFlag, bool sweepFlag)
{
double cos = Math.Cos(thetha / 180 * Math.PI);
double sin = Math.Sin(thetha / 180 * Math.PI);
double targetXTransformed = cos * nextPositionXRelative - sin * nextPositionYRelative; //rotate target point counterclockwise around the start point by [thetha] degrees, thereby practically rotating an intermediate coordinate system, which has its origin in the start point, clockwise by the same amount
double targetYTransformed = sin * nextPositionXRelative + cos * nextPositionYRelative;
var values = SampleEllipticArcBiasedNoRotation(rx, ry, targetXTransformed, targetYTransformed, largeArcFlag, sweepFlag);
List result = new List();
for (int j = 0; j < values.Item1.Length; j++)
{
double xCoordinateRelative = cos * values.Item1[j] + sin * values.Item2[j]; //rotate backwards so intermediate coordinate system and "real" coordinate system have the same rotation again
double yCoordinateRelative = cos * values.Item2[j] - sin * values.Item1[j];
double xCoordinateAbsolute = lastPositionX + xCoordinateRelative; //translate relative to absolute coordinates (intermediate coordinate system is now again aligned with the "real" one (the virtual pane on which all vectorgraphic elements are placed) (note that this "real" coordinate system is still not the same as the one actually representing pixels for drawing, as it still has to be scaled appropriately (done inside the ScaleAndCreatePoint method)))
double yCoordinateAbsolute = lastPositionY + yCoordinateRelative;
result.Add(ScaleAndCreatePoint(xCoordinateAbsolute, yCoordinateAbsolute));
}
return result;
}
///
/// samples an elliptical arc with given radii through coordinate origin and endpoint with specified properties
///
/// x radius
/// y radius
/// x coordinate of next point
/// y coordinate of next point
/// flag determining if the large or the small arc is to be drawn
/// flag determining in which direction the arc is to be drawn (false = ccw, true = cw)
///
private Tuple SampleEllipticArcBiasedNoRotation(double rx, double ry, double targetXTransformed, double targetYTransformed, bool largeArcFlag, bool sweepFlag)
{
double xStretchFactor = rx / ry; //get rx to ry ratio
var values = SampleCircleArcBiasedNoRotation(ry, targetXTransformed / xStretchFactor, targetYTransformed, largeArcFlag, sweepFlag); //get a circular arc with radius ry
for (int j = 0; j < values.Item1.Length; j++)
{
values.Item1[j] = values.Item1[j] * xStretchFactor; //correct x coordinates to get an elliptical arc from a circular one
}
return values;
}
///
/// samples a circular arc with given radius through coordinate origin and endpoint with specified properties
///
/// radius
/// x coordinate of next point
/// y coordinate of next point
/// flag determining if the large or the small arc is to be drawn
/// flag determining in which direction the arc is to be drawn (false = ccw, true = cw)
///
private Tuple SampleCircleArcBiasedNoRotation(double r, double nextPositionXRelative, double nextPositionYRelative, bool largeArcFlag, bool sweepFlag)
{
// code for center computation adapted from https://stackoverflow.com/a/36211852
double radsq = r * r;
double q = Math.Sqrt(((nextPositionXRelative) * (nextPositionXRelative)) + ((nextPositionYRelative) * (nextPositionYRelative))); //Math.Sqrt(((x2 - x1) * (x2 - x1)) + ((y2 - y1) * (y2 - y1)));
double x3 = (nextPositionXRelative) / 2; //(x1 + x2) / 2;
double y3 = (nextPositionYRelative) / 2; //(y1 + y2) / 2;
bool xPlusFlag; //flags needed to select center point "left" of the line between origin and the endpoint (will be used to select correct one ("left" or "right" one) later together with flags passed as arguments
bool yPlusFlag;
if (nextPositionXRelative > 0)
{
yPlusFlag = true; //left point lies above line
}
else
{
yPlusFlag = false; //left point lies below line
}
if (nextPositionYRelative > 0)
{
xPlusFlag = false; //left point lies left of line
}
else
{
xPlusFlag = true; //left point lies right of line
}
if (sweepFlag != largeArcFlag) //need "right" center point, not "left" one (refer to svg specification, sweepFlag means going around the circle in "clockwise" direction, largeArcFlag means tracing the larger of the two possible arcs in the selected direction)
{
xPlusFlag = !xPlusFlag;
yPlusFlag = !yPlusFlag;
}
double xC; // coordinates of center point of circle
double yC;
if (xPlusFlag) xC = x3 + Math.Sqrt(radsq - ((q / 2) * (q / 2))) * ((nextPositionYRelative) / q); //x3 + Math.Sqrt(radsq - ((q / 2) * (q / 2))) * ((y1 - y2) / q);
else xC = x3 - Math.Sqrt(radsq - ((q / 2) * (q / 2))) * ((nextPositionYRelative) / q);
if (yPlusFlag) yC = y3 + Math.Sqrt(radsq - ((q / 2) * (q / 2))) * ((nextPositionXRelative) / q); //y3 + Math.Sqrt(radsq - ((q / 2) * (q / 2))) * ((x2-x1) / q);
else yC = y3 - Math.Sqrt(radsq - ((q / 2) * (q / 2))) * ((nextPositionXRelative) / q);
var values = SampleCircleArcBiasedAroundCenter(-xC, -yC, nextPositionXRelative - xC, nextPositionYRelative - yC, r, largeArcFlag, sweepFlag);
for (int j = 0; j < values.Item1.Length; j++)
{
values.Item1[j] = values.Item1[j] + xC; //correct center point coordinate bias
values.Item2[j] = values.Item2[j] + yC;
}
return values;
}
///
/// samples a circular arc with given radius around the center from the startpoint to the endpoint in the specified direction
///
/// x coordinate of the start point
/// y coordinate of the start point
/// x coordinate of the final point
/// y coordinate of the final point
/// radius
/// direction
///
private Tuple SampleCircleArcBiasedAroundCenter(double xStartPoint, double yStartPoint, double xFinalPoint, double yFinalPoint, double r, bool largeArcFlag, bool clockwise)
{
double phiEnd = Math.Atan2(yFinalPoint, xFinalPoint); // angles between points and origin and the positive x Axis
double phiStart = Math.Atan2(yStartPoint, xStartPoint);
double angle = ((double)2 * Math.PI) / (double)samplingRateEllipse; //compute angle increment (equal to the one used for ellipses)
double angleDifference = Math.Abs(phiStart - phiEnd);
if (angleDifference > 2 * Math.PI || angleDifference < 0) throw new Exception("angleDifference out of range: " + angleDifference); //TODO remove
if (largeArcFlag) // get larger angleDifference
{
if (angleDifference < Math.PI) angleDifference = ((double)2 * Math.PI) - angleDifference; // was smaller angleDifference
}
else // get smaller angleDifference
{
if (angleDifference > Math.PI) angleDifference = ((double)2 * Math.PI) - angleDifference; // was larger angleDifference
}
int numberOfPoints = (int)Math.Ceiling(angleDifference / angle); //compute number of points to sample
double[] xValues = new double[numberOfPoints];
double[] yValues = new double[numberOfPoints];
double phiCurrent = phiStart;
for (int j = 0; j < numberOfPoints - 1; j++) //compute intermediate points
{
if (clockwise) phiCurrent -= angle; //get new angle
else phiCurrent += angle;
yValues[j] = Math.Sin(phiCurrent) * r; //angles are relative to positive x Axis!
xValues[j] = Math.Cos(phiCurrent) * r;
}
xValues[numberOfPoints - 1] = xFinalPoint; //(last segment always has an angle of less than or exactly 'angle')
yValues[numberOfPoints - 1] = yFinalPoint;
return new Tuple(xValues, yValues);
}
///
/// samples a cubic bezier curve with a static number of steps (samplingRateBezier)
///
/// x coordinate of last point
/// y coordinate of last point
/// x coordinate of control point 1
/// y coordinate of control point 1
/// x coordinate of control point 2
/// y coordinate of control point 2
/// x coordinate of next point
/// y coordinate of next point
/// a List of Points containing all sampled points
private List SampleCubicBezier(double lastPositionX, double lastPositionY, double controlPoint1X, double controlPoint1Y, double controlPoint2X, double controlPoint2Y, double nextPositionX, double nextPositionY)
{
var line1 = CreateDiscreteLine(lastPositionX, lastPositionY, controlPoint1X, controlPoint1Y);
var line2 = CreateDiscreteLine(controlPoint1X, controlPoint1Y, controlPoint2X, controlPoint2Y);
var line3 = CreateDiscreteLine(controlPoint2X, controlPoint2Y, nextPositionX, nextPositionY);
var quadraticBezier1 = ComputeBezierStep(line1.Item1, line1.Item2, line2.Item1, line2.Item2);
var quadraticBezier2 = ComputeBezierStep(line2.Item1, line2.Item2, line3.Item1, line3.Item2);
var values = ComputeBezierStep(quadraticBezier1.Item1, quadraticBezier1.Item2, quadraticBezier2.Item1, quadraticBezier2.Item2);
List result = new List();
for (int j = 0; j < samplingRateBezier; j++)
{
result.Add(ScaleAndCreatePoint(values.Item1[j], values.Item2[j]));
}
return result;
}
///
/// samples a quadratic bezier curve with a static number of steps (samplingRateBezier)
///
/// x coordinate of last point
/// y coordinate of last point
/// x coordinate of control point
/// y coordinate of control point
/// x coordinate of next point
/// y coordinate of next point
/// a List of Points containing all sampled points
private List SampleQuadraticBezier(double lastPositionX, double lastPositionY, double controlPointX, double controlPointY, double nextPositionX, double nextPositionY)
{
var line1 = CreateDiscreteLine(lastPositionX, lastPositionY, controlPointX, controlPointY);
var line2 = CreateDiscreteLine(controlPointX, controlPointY, nextPositionX, nextPositionY);
var values = ComputeBezierStep(line1.Item1, line1.Item2, line2.Item1, line2.Item2);
List result = new List();
for (int j = 0; j < samplingRateBezier; j++)
{
result.Add(ScaleAndCreatePoint(values.Item1[j], values.Item2[j]));
}
return result;
}
///
/// create a discrete line with [samplingRateBezier] points (including start and end point) between two points
///
/// coordinate of point 1
/// y coordinate of point 1
/// x coordinate of point 2
/// y coordinate of point 2
/// the discrete line as arrays of x and y coordinates
private Tuple CreateDiscreteLine(double point1X, double point1Y, double point2X, double point2Y)
{
double[] resultX = new double[samplingRateBezier];
double[] resultY = new double[samplingRateBezier];
for (int j = 0; j < samplingRateBezier; j++)
{
var pointResult = LinearInterpolationForBezier(point1X, point1Y, point2X, point2Y, j);
resultX[j] = pointResult.Item1;
resultY[j] = pointResult.Item2;
}
return new Tuple(resultX, resultY);
}
///
/// computes the discrete bezier curve between two given dicrete lines/curves
///
/// x coordinates of all points in line 1
/// y coordinates of all points in line 1
/// x coordinates of all points in line 2
/// y coordinates of all points in line 2
/// the discrete bezier curve
private Tuple ComputeBezierStep(double[] line1X, double[] line1Y, double[] line2X, double[] line2Y)
{
double[] resultX = new double[samplingRateBezier];
double[] resultY = new double[samplingRateBezier];
for (int j = 0; j < samplingRateBezier; j++)
{
var pointResult = LinearInterpolationForBezier(line1X[j], line1Y[j], line2X[j], line2Y[j], j);
resultX[j] = pointResult.Item1;
resultY[j] = pointResult.Item2;
}
return new Tuple(resultX, resultY);
}
///
/// creates the linearly interpolated point at j/(samplingRateBezier - 1) between point 1 and point 2
///
/// x coordinate of point 1
/// y coordinate of point 1
/// x coordinate of point 2
/// y coordinate of point 2
/// number of point to be interpolated, at a total number of [samplingRateBezier] points
/// the linearly interpolated point
private Tuple LinearInterpolationForBezier(double point1X, double point1Y, double point2X, double point2Y, int j)
{
double factor = ((double)1 / (double)(samplingRateBezier - 1)) * (double)j; //factor for linear interpolation
double x = point1X + ((point2X - point1X) * factor);
double y = point1Y + ((point2Y - point1Y) * factor);
return new Tuple(x, y);
}
///
/// parses a hierarchical svg element and all its sub-elements
///
/// the definition of the top level element as whitespace seperated String[]
/// an array holding all lines of the input file
/// the parsed element as a Line object, or null if the element is not supported
private List ParseMultiLineSVGElement(string[] currentElement, string[] allLines)
{
throw new NotImplementedException();
}
///
/// removes the name of the attribute aswell as the '="' at the beginning and the '"' or '">' at the end of an attribute definition
///
/// the definition from the svg file
/// the value of the attribute, as String (the part of definition contained between '"'s)
private String ParseSingleSVGAttribute(String definition)
{
return definition.Split('"')[1];
}
///
/// fetches a single svg element definition that may extend ovr several lines of the input file, iterates i to point to the last line of the element definition
///
/// an array holding all lines of the input file
/// the definition of the current svg element, as String[] split by whitespaces
private String[] GetCurrentElement(String[] allLines)
{
List currentElementTemp = allLines[i].Split(whitespaces).ToList();
while (!currentElementTemp.Last().EndsWith(">"))
{
i++;
currentElementTemp.AddRange(allLines[i].Split(whitespaces).ToList());
}
return currentElementTemp.ToArray();
}
///
/// applies the scale factor to the coordinates and creates a new Point
///
/// unscaled x coordinate
/// unscaled y coordinate
/// new Point with scaled coordinates
private Point ScaleAndCreatePoint(double x, double y)
{
return new Point((int)Math.Round(x * scale), (int)Math.Round(y * scale));
}
///
/// creates a representation of an ellipse as a List of Points by sampling the outline of the ellipse
///
/// x coordinate of the center of the ellipse
/// y coordinate of the center of the ellipse
/// x radius of the ellipse
/// y radius of the ellipse
/// the parsed element as a List of Points
private List SampleEllipse(double x, double y, double rx, double ry)
{
List ellipse = new List();
double angle = ((double)2 * Math.PI) / (double)samplingRateEllipse;
double yScale = ry / rx;
double[] xValues = new double[samplingRateEllipse / 4];
double[] yValues = new double[samplingRateEllipse / 4];
for (int j = 0; j < samplingRateEllipse / 4; j++) //compute offset values of points for one quadrant
{
xValues[j] = Math.Sin((double)j * angle) * rx;
yValues[j] = Math.Cos((double)j * angle) * rx;
}
for (int j = 0; j < samplingRateEllipse / 4; j++) //create actual points for first quadrant
{
int xCoord = Convert.ToInt32(Math.Round(x + xValues[j]));
int yCoord = Convert.ToInt32(Math.Round(y - yValues[j] * yScale));
ellipse.Add(ScaleAndCreatePoint(xCoord, yCoord));
}
for (int j = 0; j < samplingRateEllipse / 4; j++) //create actual points for second quadrant
{
int xCoord = Convert.ToInt32(Math.Round(x + yValues[j]));
int yCoord = Convert.ToInt32(Math.Round(y + xValues[j] * yScale));
ellipse.Add(ScaleAndCreatePoint(xCoord, yCoord));
}
for (int j = 0; j < samplingRateEllipse / 4; j++) //create actual points for third quadrant
{
int xCoord = Convert.ToInt32(Math.Round(x - xValues[j]));
int yCoord = Convert.ToInt32(Math.Round(y + yValues[j] * yScale));
ellipse.Add(ScaleAndCreatePoint(xCoord, yCoord));
}
for (int j = 0; j < samplingRateEllipse / 4; j++) //create actual points for fourth quadrant
{
int xCoord = Convert.ToInt32(Math.Round(x - yValues[j]));
int yCoord = Convert.ToInt32(Math.Round(y - xValues[j] * yScale));
ellipse.Add(ScaleAndCreatePoint(xCoord, yCoord));
}
ellipse.Add(ScaleAndCreatePoint(Convert.ToInt32(Math.Round(x + 0)), Convert.ToInt32(Math.Round(y - rx * yScale)))); //close ellipse
return ellipse;
}
}
}