thodg/exterm/lib/ttf/glyph.ex

• Show log

  Commit

• Hash : 47faab2d
  Author : Thomas de Grivel
  Date : 2022-02-12T10:55:20
  

  wip glyphs

Download

• lib/ttf/glyph.ex

• defmodule TTF.Glyph do
  
    defstruct bounding_box: nil, codepoint: nil, contour_count: nil, contour_endpoint_indexes: nil, contours: nil, control_points: nil, flags: nil, n_points: nil, name: nil, ttf: nil
  
    def contour_segments([]) do
      []
    end
    def contour_segments(contour) do
      length = Enum.count(contour)
      i = 1
      stack = nil
      next = nil
      start = Enum.at(contour, 0)
      mid = nil
      end_ = nil
      segments = []
      contour_segments(contour, length, i, stack, next, start, mid, end_, segments)
    end
  
    def contour_segments(contour, length, i, stack, next, start, mid, end_, segments) do
      mid = nil
      {next, i} = contour_next_point(contour, length, i)
      if next == nil do
        mid = stack
        end_ = Enum.at(contour, 0)
        contour_segments_body(contour, length, i, stack, next, start, mid, end_, segments)
      else
        if next.on_curve? do
          end_ = next
          mid = stack
          stack = nil
          contour_segments_body(contour, length, i, stack, next, start, mid, end_, segments)
        else
          if stack != nil do
            mid = stack
            end_ = midpoint(stack, next)
            stack = next
            contour_segments_body(contour, length, i, stack, next, start, mid, end_, segments)
          else
            stack = next
            contour_segments(contour, length, i, stack, next, start, mid, end_, segments)
          end
        end
      end
    end
  
    defp contour_segments_body(contour, length, i, stack, next, start, mid, end_, segments) do
      segment = %{a: start, b: mid, c: end_}
      if next != nil do
        start = end_
        contour_segments(contour, length, i, stack, next, start, mid, end_, [segment | segments])
      else
        segments |> Enum.reverse()
      end
    end
  
    defp contour_next_point(contour, length, i) do
      if i < length do
        {Enum.at(contour, i), i + 1}
      else
        {nil, i}
      end
    end
  
    defp midpoint(p0, p1) do
      %TTF.ControlPoint{x: (p0.x + p1.x) / 2.0,
                        y: (p0.y + p1.y) / 2.0,
                        on_curve?: true}
    end
  
  end
  

Download