Portability | portable |
---|---|

Stability | stable |

Maintainer | Tillmann Vogt <tillk.vogt@googlemail.com> |

Safe Haskell | None |

Parsing the SVG path command, see http://www.w3.org/TR/SVG/paths.html#PathData :

- pathFromString :: String -> IO [PathCommand]
- data PathCommand
- commandsToPoints :: [PathCommand] -> F2 -> F2 -> [[F2]]
- ctp :: [PathCommand] -> [F2] -> F2 -> Bool -> F2 -> F2 -> [[F2]]
- bSubCurve :: Bool -> (X, Y) -> [F2] -> [F2]

# Documentation

pathFromString :: String -> IO [PathCommand]Source

convert a SVG path string into a list of commands

data PathCommand Source

M_abs Tup | Establish a new current point (with absolute coords) |

M_rel Tup | Establish a new current point (with coords relative to the current point) |

Z | Close current subpath by drawing a straight line from current point to current subpath's initial point |

L_abs Tup | A line from the current point to Tup which becomes the new current point |

L_rel Tup | |

H_abs X | A horizontal line from the current point (cpx, cpy) to (x, cpy) |

H_rel X | |

V_abs Y | A vertical line from the current point (cpx, cpy) to (cpx, y) |

V_rel Y | |

C_abs (X1, Y1, X2, Y2, X, Y) | Draws a cubic Bézier curve from the current point to (x,y) using (x1,y1) as the ^control point at the beginning of the curve and (x2,y2) as the control point at the end of the curve. |

C_rel (X1, Y1, X2, Y2, X, Y) | |

S_abs (X2, Y2, X, Y) | Draws a cubic Bézier curve from the current point to (x,y). The first control point is assumed to be the reflection of the second control point on the previous command relative to the current point. (If there is no previous command or if the previous command was not an C, c, S or s, assume the first control point is coincident with the current point.) (x2,y2) is the second control point (i.e., the control point at the end of the curve). |

S_rel (X2, Y2, X, Y) | |

Q_abs (X1, Y1, X, Y) | A quadr. Bézier curve from the curr. point to (x,y) using (x1,y1) as the control point |

Q_rel (X1, Y1, X, Y) | Nearly the same as cubic, but with one point less |

T_abs Tup | T_Abs = Shorthand/smooth quadratic Bezier curveto |

T_rel Tup | |

A_abs | A = Elliptic arc (not used) |

A_rel |

commandsToPoints :: [PathCommand] -> F2 -> F2 -> [[F2]]Source

convert path-commands to outline points

ctp :: [PathCommand] -> [F2] -> F2 -> Bool -> F2 -> F2 -> [[F2]]Source

bSubCurve :: Bool -> (X, Y) -> [F2] -> [F2]Source

bSubcurve uses bezier subdivision. (inspired by Hersch, Font Rasterization: the State of the Art (freely available)) It divides an arc into two arcs recursively until the arc is either completely between two vertical raster lines or completely between two horizontal raster lines or the line is at most 1 pixel long. This function computes outline points (tex==False) as well as border points for rasterisation (tex==True) by using an x-, y-resoultion raster. dx, dy is the width and height of a pixel of this raster.