Loading ...
Sorry, an error occurred while loading the content.

autotrace partial outline processing

Expand Messages
  • tommckearney
    I sent this message directly to the email address on Autotrace s homepage, but, since it doesn t seem to have been actively developed for quite a while, I
    Message 1 of 1 , Mar 24, 2006
    • 0 Attachment
      I sent this message directly to the email address on Autotrace's
      homepage, but, since it doesn't seem to have been actively developed
      for quite a while, I decided to repost it here.

      As an update, I made the changes the way they made sense to me and
      things seem to work fine. I'm wondering if I'm dealing with a
      cut-and-paste issue (centerline processing came after the
      outline/contour functionality) or whether I'm just not understanding
      something.

      I will eventually be submitting my code changes to the project once
      it's cleaned up and ready for general consumption.

      Tom

      -------- ORIGINAL EMAIL ----------

      Hello Martin.

      I'd like to start by thanking you for developing Autotrace. I am
      currently making some modifications.
      I have added support for the Stentiford thinning algorithm. I don't
      know if it is better, but we were already using it elsewhere, so I
      figured it would be faster to have it in Autotrace. I also added
      support for just dumping the Splines to a text file for easy parsing
      by other programs rather than all the other formats.

      I have a question about the partial outline code (pxl-outline.c)

      I have a situation where this is not working.

      My text diagram:

      X = already in the original open "outline"
      W = I want this pixel too
      U = Used in another curve

      ---U-
      ---WU
      --X--
      --X--
      -X---

      In this case, an open outline is found, starting from the upper-most X
      going SOUTH.
      When it is finished, it tries to find another partial outline to
      combine with. Here is where I get confused.

      If we're going SOUTH, it tries to find partial outlines in the
      following directional order:
      EAST
      SOUTHEAST
      SOUTHWEST
      end-of-list

      The comment states "If the outline is open (i.e., we didn't return to
      the starting pixel), search from the starting pixel in the opposite
      direction and concatenate the two outlines."

      How is this the "opposite direction" ?

      I would assume that it would use:
      NORTH
      NORTHEAST
      NORTHWEST

      Can you help me understand this? I don't want to break anything that
      I don't understand.

      Thank you in advance for any help you can give me.

      Tom McKearney
    Your message has been successfully submitted and would be delivered to recipients shortly.