Page 1 of 2 12 LastLast
Results 1 to 10 of 11

Thread: Creating interactive GIMP brushes

  1. #1
    Guild Journeyer eepjr24's Avatar
    Join Date
    Nov 2020
    Location
    East Coast, USA
    Posts
    150

    Default Creating interactive GIMP brushes

    So I am not one to start simple, apparently. I started GIMP a couple weeks ago and I am now in the process of teaching myself Python to help automate interactive brush creation. Anyway, here is what I am trying.

    I'd like to make a brush that emulates wagon tracks. I am currently working on a brush canvas about 70x70 pixels, mostly transparent with some blurred dots to represent the tracks. I have 72 images in the brush, single dimensional tied in 5 degree steps to the angular selection.

    I am just not having much luck getting it to look like I am after and wondering if anyone knows of a good tutorial that I could take a look at or another angular brush I could deconstruct as an example? If you'd like the gih I have made so far I am happy to share, but ideally pointing me in the right direction usually helps me learn better.

    Thanks in advance.

    - Ernie

  2. #2
    Administrator Redrobes's Avatar
    Join Date
    Dec 2007
    Location
    England
    Posts
    7,256
    Blog Entries
    8

    Default

    I thought that GIMP supported "image tubes" which I think is exactly what you want. Its where you have a collection of brushes and as you draw with them it splats them down in tube order one after the other. Sometimes, art programs allow you to vary the size and orientation of the splats by a certain random amount every time. See if there is a GIMP extension to do them. I recall somewhere that it could support paint shop pro compatible image tubes. But then I am senile so who knows

    Edit: Ahh not so senile after all...
    https://www.gimp.org/tutorials/Image_Pipes/

  3. #3
    Guild Journeyer eepjr24's Avatar
    Join Date
    Nov 2020
    Location
    East Coast, USA
    Posts
    150

    Default

    Quote Originally Posted by Redrobes View Post
    I thought that GIMP supported "image tubes" which I think is exactly what you want. Its where you have a collection of brushes and as you draw with them it splats them down in tube order one after the other. Sometimes, art programs allow you to vary the size and orientation of the splats by a certain random amount every time. See if there is a GIMP extension to do them. I recall somewhere that it could support paint shop pro compatible image tubes. But then I am senile so who knows

    Edit: Ahh not so senile after all...
    https://www.gimp.org/tutorials/Image_Pipes/
    Yep, that's what I am trying to do, but looking for something a bit more in depth than what I have been able to find. I have an image pipe with 72 images in it currently, each one corresponding to a 5 degree angular brush direction. But that results in something like this:

    Capture.jpg

  4. #4
    Professional Artist Tiana's Avatar
    Join Date
    Oct 2009
    Location
    Winnipeg, Manitoba, Canada!
    Posts
    1,825

    Default

    If you switch to using Clip Studio Paint let me know and I'll give you my tracks brush. It's only made out of a couple of pieces in the ribbon tube. Yours is likely bugging out because it's not aware which 5 degree angle to pick on, although it does look like Gimp has the complexity to do what you want maybe you could try with just a single horizontal loop and set it up as a repeating ribbon.

    Click my banner, behold my art! Fantasy maps for Dungeons and Dragons, RPGS, novels.
    No obligation, free quotes. I also make custom PC / NPC / monster tokens.
    Contact me: calthyechild@gmail.com or _ti_ (Discord) to discuss a map!


  5. #5

    Default

    Quote Originally Posted by eepjr24 View Post
    I'd like to make a brush that emulates wagon tracks. I am currently working on a brush canvas about 70x70 pixels, mostly transparent with some blurred dots to represent the tracks. I have 72 images in the brush, single dimensional tied in 5 degree steps to the angular selection.
    - Ernie
    Hi Ernie - the latest versions of Gimp have some pretty powerful brush dynamics, and you can likely do what you want without needing to build an image tube/GIH brush. Do you have an example of the results you are looking for?

    -Rob A>

  6. #6
    Guild Journeyer eepjr24's Avatar
    Join Date
    Nov 2020
    Location
    East Coast, USA
    Posts
    150

    Default

    Quote Originally Posted by RobA View Post
    Hi Ernie - the latest versions of Gimp have some pretty powerful brush dynamics, and you can likely do what you want without needing to build an image tube/GIH brush. Do you have an example of the results you are looking for?

    -Rob A>
    Sure. In the end, I believe I am going to need to use GIH for other things as well, which is part of why I am wanting to figure them out. I'd like to emulate some of the features I want in the wagon wheel brush to paint buildings along a path from a GIH as well, for example. But see below for something close to what I am trying to achieve. I'd like to be able to vary the pressure and jitter a little bit as well in the long run.

    wagon_trail_example.jpg

    - E

  7. #7

    Default

    Sorry, but it just won't work in Gimp given the way brushes work. The closest I've come with a double track brush is to make it bow-tie shaped with faded edges to allow for the angles without overlapping. You don;t need to make a GIH, just a single brush and enable brush dynamics, pickling "Track Direction", which will do the rotating for you. But it will never form clean cart tracks/lines.

    If you are comfortable working with paths, it is better to to this making three strokes along the same path - one wide soft stroke in the lighter colour to make the outline, then one harder dark stroke to make the main track, then a smaller hard stroke in the light colour again to "clear" the space between the tracks. Here is an example done that way:
    tracks.jpg

    -Rob A>

  8. #8

    Default

    And here is a post from 13 years ago where I attached a building brush you can play with if desired. Might give you some inspiration. But again, it could be simplified with the current Gimp version, as you can use the GIH to provide random building shapes and the track direction dynamic to rotate them to follow the street orientation.

    https://www.cartographersguild.com/showthread.php?t=545

    -Rob A>

  9. #9
    Guild Journeyer eepjr24's Avatar
    Join Date
    Nov 2020
    Location
    East Coast, USA
    Posts
    150

    Default

    Quote Originally Posted by RobA View Post
    Sorry, but it just won't work in Gimp given the way brushes work. The closest I've come with a double track brush is to make it bow-tie shaped with faded edges to allow for the angles without overlapping. You don;t need to make a GIH, just a single brush and enable brush dynamics, pickling "Track Direction", which will do the rotating for you. But it will never form clean cart tracks/lines.

    If you are comfortable working with paths, it is better to to this making three strokes along the same path - one wide soft stroke in the lighter colour to make the outline, then one harder dark stroke to make the main track, then a smaller hard stroke in the light colour again to "clear" the space between the tracks. Here is an example done that way:
    tracks.jpg

    -Rob A>
    I built the screen shot with selections and stroking. =) I am trying to make it so I don't have to do that. You can skip one step in the process if you use a 4px hard brush and just shrink the path or selection by 8px before you stroke it. I suppose I can just make it a plugin that takes a selection and puts the wagon tracks on it. Just trying to make things automated and reduce clicks to whatever extent is possible.

  10. #10
    Guild Journeyer eepjr24's Avatar
    Join Date
    Nov 2020
    Location
    East Coast, USA
    Posts
    150

    Default

    Quote Originally Posted by RobA View Post
    And here is a post from 13 years ago where I attached a building brush you can play with if desired. Might give you some inspiration. But again, it could be simplified with the current Gimp version, as you can use the GIH to provide random building shapes and the track direction dynamic to rotate them to follow the street orientation.

    https://www.cartographersguild.com/showthread.php?t=545

    -Rob A>
    Thanks, I will take a look for sure!

    - E

Page 1 of 2 12 LastLast

Tags for this Thread

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •