Extending
                                   Tux Paint
                                version 0.9.34

        Copyright © 2002-2024 by various contributors; see AUTHORS.txt.
                             https://tuxpaint.org/

                               október 10, 2024

+-----------------------------------------+
|            Table of Contents            |
|-----------------------------------------|
|   * Where Files Go                      |
|       + Standard Files                  |
|       + Personal Files                  |
|   * Brushes                             |
|       + Brush Descriptive Text          |
|       + Brush Options                   |
|   * Stamps                              |
|       + Stamp Images                    |
|       + Stamp Descriptive Text          |
|       + Stamp Sound Effects             |
|       + Stamp Descriptive Sound         |
|       + Stamp Options                   |
|       + Pre-Mirrored and Flipped Stamps |
|   * Fonts                               |
|   * 'Starters'                          |
|       + Coloring-Book Style Starters    |
|       + Scene-Style Starters            |
|       + Starter Options                 |
|   * 'Templates'                         |
|       + Template Options                |
|   * Translations                        |
|   * Alternative Input Methods           |
|   * On-screen Keyboard                  |
|   * Magic Tools                         |
+-----------------------------------------+

If you wish to add or change things like Brushes, Starters, Rubber Stamps, and
other content used by Tux Paint, you can do so fairly easily by simply adding,
changing, or removing files where Tux Paint looks for them.

💡 Note: You'll need to re-launch Tux Paint for the changes to take effect.

Where Files Go

                            ### Standard Files ###

Tux Paint looks for its various data files in its 'data' directory.

→ Linux and Unix ←

    Where this directory goes depends on what value was set for "DATA_PREFIX"
    when Tux Paint was built. See 'Install documentation' for details.

    By default, though, the directory is:

        /usr/local/share/tuxpaint/

    If you installed from a package, it is more likely to be:

        /usr/share/tuxpaint/


     
→ Windows ←

    Tux Paint looks for a directory called 'data' in the same directory as the
    executable. This is the directory that the installer used when installing
    Tux Paint e.g.:

        C:\Program Files\TuxPaint\data


     
→ macOS ←

    Tux Paint stores its data files inside the "Tux Paint" application icon
    (which is actually a special kind of folder on macOS & Mac OS X before it).
    The following steps explain how to get to the folders within it:

     1. Bring up a 'context' menu by holding the [Control] key and clicking the
        Tux Paint icon the in Finder. (If you have a mouse with more than one
        button, you can simply right-click the icon.)
     2. Select "Show Contents" from the menu that appears. A new Finder window
        will appear with a folder inside called "Contents".
     3. Open the "Contents" folder and open the "Resources" folder found
        inside.
     4. There, you will find various sub-folders, such as "starters", "stamps",
        "brushes", etc. Adding new content to these folders will make the
        content available to any user that launches this copy (icon) of Tux
        Paint.

    💡 Note: If you install a newer version of Tux Paint and replace or discard
    the old version, you will lose changes made by following the instructions
    above, so keep backups of your new content (stamps, brushes, etc.).

    Tux Paint also looks for files in a "TuxPaint" folder that you can place in
    your system's "Application Support" folder (found under "Library" at the
    root of your filesystem):

        /Library/Application Support/TuxPaint/data/

    When you upgrade to a newer version of Tux Paint, the contents of this
    "TuxPaint" folder will stay the same, and remain accessible by all users of
    Tux Paint.


     

                            ### Personal Files ###

You can also create brushes, stamps, 'starters', templates, and fonts in your
own user account directory (folder) for Tux Paint to find.

→ Windows ←

    Your personal Tux Paint folder is stored in your personal "Application
    Data". For example, on newer Windows:

        C:\Users\username\AppData\Roaming\TuxPaint\


     
→ macOS ←

    Your personal Tux Paint folder is stored in your personal 
    "Application Support" folder:

        /Users/username/Library/Application Support/TuxPaint/


     
→ Linux and Unix ←

    Your personal Tux Paint files go into a 'hidden directory' found in your
    account's home directory: "/home/username/.tuxpaint/".

    Don't forget the period (".") before the "tuxpaint"!


     

To add your own brushes, stamps, 'starters,' templates, and fonts, create
subdirectories under your personal Tux Paint directory named "brushes", "stamps
", "starters", "templates", "fonts", respectively.

(For example, if you created a brush named "flower.png", you would put it in 
"/home/username/.tuxpaint/brushes/" under Linux or Unix.)

Brushes

The brushes used for drawing with the 'Paint' and 'Lines' tools in Tux Paint
are simply PNG image files.

The alpha (transparency) of the PNG image is used to determine the shape of the
brush, which means that the shape can be 'anti-aliased' and even
partially-transparent!

Greyscale pixels in the brush PNG will be drawn using the currently-selected
color in Tux Paint. Color pixels will be tinted.

                        ### Brush Descriptive Text ###

Tux Paint will display descriptive text when a brush is selected. These are
placed in plain text files with the same name as the PNG, but with a ".txt"
filename extension. (e.g., "brush.png"'s description is stored in "brush.txt"
in the same directory.)

The first line of the text file will be used as the US English description of
the brush's image. It must be encoded in UTF-8.

→ Localization Support ←

    Additional lines can be added to the text file to provide translations of
    the description, to be displayed when Tux Paint is running in a different
    locale (like French or Spanish).

    The beginning of the line should correspond to the language code of the
    language in question (e.g., "fr" for French, and "zh_TW" for Traditional
    Chinese), followed by ".utf8=" and the translated description (Unicode,
    encoded in UTF-8).

    For Tux Paint developers: There are scripts in the "brushes-po" directory
    for converting the text files to PO format (and back) for easy translation
    to different languages. Therefore you should never add or change
    translations in the ".txt" files directly.

    If no translation is available for the language Tux Paint is currently
    running in, the US English text is used.


     
→ Windows Users ←

    Use NotePad or WordPad to edit/create these files. Be sure to save them as
    plain-text, and make sure they have a ".txt" extension at the end of the
    filename.


     

                             ### Brush Options ###

Aside from a graphical shape, brushes can also be given other attributes. To do
this, you need to create a 'data file' for the brush.

A brush's data file is simply a plain ASCII text file containing the options
for the brush.

The file has the same name as the PNG image, but a ".dat" extension. (e.g.,
"brush.png"'s data file is the text file "brush.dat", found in the same
directory.)

→ Brush Spacing ←

    As of Tux Paint version 0.9.16, you can now specify the spacing for brushes
    (that is, how often they are drawn). By default, the spacing will be the
    brush's height, divided by 4.

    Add a line containing the line "spacing=N" to the brush's data file, where
    "N" is the spacing you want for the brush. (The lower the number, the more
    often the brush is drawn.)


     
→ Animated Brushes ←

    As of Tux Paint version 0.9.16, you may now create animated brushes. As the
    brush is used, each frame of the animation is drawn.

    Lay each frame out across a wide PNG image. For example, if your brush is
    30x30 and you have 5 frames, the image should be 150x30.

    Add a line containing the line "frames=N" to the brush's data file, where "
    N" is the number of frames in the brush.

    ⚙ Note: If you'd rather the frames be flipped through randomly, rather than
    sequentially, also add a line containing "random" to the brush's data file.


     
→ Directional Brushes ←

    As of Tux Paint version 0.9.16, you may now create directional brushes. As
    the brush is used, different shapes are drawn, depending on the direction
    the brush is going.

    The directional shapes are divided into a 3x3 square in a PNG image. For
    example, if your brush is 30x30, the image should be 90x90, and each of the
    direction's shapes placed in a 3x3 grid. The center region is used for no
    motion. The top right is used for motion that's both up, and to the right.
    And so on.

    Add a line containing the word "directional" to the brush's data file.


     
→ Rotating Brushes ←

    As of Tux Paint version 0.9.27, you may now create rotating brushes. As the
    brush is used, it is rotated 360 degrees, depending on the direction the
    brush is going.

    Add a line containing the word "rotate" to the brush's data file.


     
→ Chaotic Brushes ←

    As of Tux Paint version 0.9.34, brushes can be configured to continuously
    pick random directions as you draw with them.

    Add a line containing the word "chaotic" to the brush's data file.


     
→ Animated Directional, Rotating, or Chaotic Brushes ←

    You may mix both animated and either directional, rotating, or chaotic
    features into one brush. Use both options desired ("frames=N" and "
    directional", "rotate", or "chaotic"), in separate lines in the brush's
    ".dat" file.

    For directional brushes, lay the brush out so that each 3x3 set of
    directional shapes are laid out across a wide PNG image. For example, if
    the brush is 30x30 and there are 5 frames, it would be 450x90. (The
    leftmost 150x90 pixels of the image represent the 9 direction shapes for
    the first frame, for example.)


     

Place the brush image PNGs (and any data text files) in the "brushes"
directory.

💡 Note: If your new brushes all come out as solid squares or rectangles, it's
because you forgot to use alpha transparency! See the 'PNG documentation' in
Tux Paint for more information and tips.

Stamps

All stamp-related files go in the "stamps" directory. It's useful to create
subdirectories and sub-subdirectories there to organize the stamps. (For
example, you can have a "holidays" folder with "halloween" and "christmas"
sub-folders.)

                             ### Stamp Images ###

Rubber Stamps in Tux Paint can be made up of a number of separate files. The
one file that is required is, of course, the picture itself.

As of Tux Paint version 0.9.17, Stamps may be either PNG bitmap images or SVG
vector images. They can be full-color or greyscale. The alpha (transparency)
channel of PNGs is used to determine the actual shape of the picture (otherwise
you'll stamp a large rectangle on your drawings).

PNGs can be any size, and Tux Paint (by default) provides a set of sizing
buttons to let the user scale the stamp up (larger) and down (smaller).

SVGs are vector-based, and will be scaled appropriately for the canvas size
being used in Tux Paint.

💡 Note: If your new PNG-based stamps all come out as solid squares or
rectangles, it's because you forgot to use alpha transparency! See the 'PNG
documentation' in Tux Paint for more information and tips.

💡 Note: If your new SVG stamps seem to have a lot of whitespace, make sure the
SVG 'document' is no larger than the shape(s) within. If they are being
clipped, make sure the 'document' is large enough to contain the shape(s). See
the 'SVG documentation' in Tux Paint for more information and tips.

⚙ Advanced Users: The 'Advanced Stamps How-To' document describes, in detail,
how to make PNG images which will scale perfectly when used as stamps in Tux
Paint.

                        ### Stamp Descriptive Text ###

Tux Paint will display descriptive text when a stamp is selected. These are
placed in plain text files with the same name as the PNG or SVG, but with a
".txt" filename extension. (e.g., "stamp.png"'s description is stored in
"stamp.txt" in the same directory.)

The first line of the text file will be used as the US English description of
the stamp's image. It must be encoded in UTF-8.

→ Localization Support ←

    Additional lines can be added to the text file to provide translations of
    the description, to be displayed when Tux Paint is running in a different
    locale (like French or Spanish).

    The beginning of the line should correspond to the language code of the
    language in question (e.g., "fr" for French, and "zh_TW" for Traditional
    Chinese), followed by ".utf8=" and the translated description (Unicode,
    encoded in UTF-8).

    For Tux Paint developers: There are scripts in the "po" directory for
    converting the text files to PO format (and back) for easy translation to
    different languages. Therefore you should never add or change translations
    in the ".txt" files directly.

    If no translation is available for the language Tux Paint is currently
    running in, the US English text is used.


     
→ Windows Users ←

    Use NotePad or WordPad to edit/create these files. Be sure to save them as
    plain-text, and make sure they have a ".txt" extension at the end of the
    filename.


     

                          ### Stamp Sound Effects ###

Tux Paint can play a sound effect when a stamp is selected. For example, the
sound of a duck quaking when selecting a duck, or a brief piece of music when a
musical instrument is chosen. Files may be in "WAVE (".wav")" or "OGG Vorbis
(".ogg")" formats, and are given same name as the PNG or SVG image. (e.g.,
"stamp.svg"'s sound effect is the sound file "stamp.ogg" in the same
directory.)

→ Localization Support ←

    For sounds for different locales (e.g., if the sound is someone saying a
    word, and you want translated versions of the word said), also create WAV
    or OGG files with the locale's label in the filename, in the form:
    "stamp_LOCALE.EXT"

    The sound effect that will be played when the stamp corresponding to the
    image file "stamp.png" is selected, and when Tux Paint is using the Spanish
    locale, would be "stamp_es.wav". Under the French locale, it would be
    "stamp_fr.wav". Under the Brazilian Portuguese locale, "stamp_pt_BR.wav".
    And so on...

    If no localized sound effect can be loaded, Tux Paint will attempt to load
    the 'default' sound file. (e.g., "stamp.wav")


     

💡 Note: Also consider using descriptive sounds; see 'Stamp Descriptive Sound',
below.

                        ### Stamp Descriptive Sound ###

Tux Paint can also play a descriptive sound when a stamp is selected. For
example, the sound of someone saying the word "duck" when selecting a duck, or
the name of a musical instrument when one is chosen. Files may be in "WAVE
(".wav")" or "OGG Vorbis (".ogg")" formats, and are given same name as the PNG
or SVG image, with "_desc" at the end. (e.g., "stamp.svg"'s descriptive sound
is the sound file "stamp_desc.ogg" in the same directory.)

→ Localization Support ←

    For descriptive sounds for different locales, also create WAV or OGG files
    with both "_desc" and the locale's label in the filename, in the form:
    "stamp_desc_LOCALE.EXT"

    The descriptive sound that will be played when the stamp corresponding to
    the image file "stamp.png" is selected, and when Tux Paint is using the
    Spanish locale, would be "stamp_desc_es.wav". Under the French locale, it
    would be "stamp_desc_fr.wav". Under the Brazilian Portuguese locale,
    "stamp_desc_pt_BR.wav". And so on...

    If no localized descriptive sound can be loaded, Tux Paint will attempt to
    load the 'default' sound file. (e.g., "stamp_desc.wav")


     

                             ### Stamp Options ###

Aside from a graphical shape, a textual description, a sound effect, and a
descriptive sound, stamps can also be given other attributes. To do this, you
need to create a 'data file' for the stamp.

A stamp's data file is simply a plain ASCII text file containing the options
for the stamp.

The file has the same name as the PNG or SVG image, but a ".dat" extension.
(e.g., "stamp.png"'s data file is the text file "stamp.dat", found in the same
directory.)

→ Colored Stamps ←

    Stamps can be made to be either "colorable" or "tintable."

    → Colorable ←

        "Colorable" stamps they work much like brushes - you pick the stamp to
        get the shape, and then pick the color you want it to be. (Symbol
        stamps, like the mathematical and musical ones, are an example.)

        Nothing about the original image is used except the transparency (from
        "alpha" channel). The color of the stamp comes out solid.

        Add a line containing the word "colorable" to the stamp's data file.


         
    → Tinted ←

        "Tinted" stamps are similar to "colorable" ones, except the details of
        the original image are kept. (To put it technically, the original image
        is used, but its hue is changed, based on the currently-selected
        color.)

        Add a line containing the word "tintable" to the stamp's data file.


         
    → Tinting Options: ←

        Depending on the contents of your stamp, you might want to have Tux
        Paint use one of a number of methods when tinting it. Add one of the
        following lines to the stamp's data file:

        → Normal tinter — "tinter=normal" (the default) ←
            This is the normal tinting mode. First, the primary hue of the
            stamp is determined. (For example, a picture of a flower with a
            stem will have the petal color seen as the primary hue of the
            overall image.) Next, the most highly saturated part of the picture
            is found. With "normal tinter", the range of hue used to do this
            starts out within ±18° of the pimary hue found in step 1. (If none
            can be found, it widens the range by 50% and tries again.) Finally,
            the image is tinted. Anything falling within 50% of the range
            (e.g., ±27°) is altered to have the hue of the color chosen by the
            user.
             
        → Narrow tinter — "tinter=narrow" ←
            This like the "normal" option described above, but starts a
            narrower hue range of ±6°. Anything found within 50% of the range
            (e.g. ±9°) is tinted. If too much of your stamp is being tinted,
            try this option.
             
        → 'Any hue' tinter — "tinter=anyhue" ←
            This remaps all hues in the stamp. It works similarly to the
            "anyhue" and "narrow" options described above, but the hue range is
            ±180°.
             
        → Vector tinter — "tinter=vector" ←
            This maps 'black through white' to 'black through destination'.
             

         

     
→ Unalterable Stamps ←

    By default, a stamp can be flipped upside down, shown as a mirror image, or
    both. This is done using the control buttons below the stamp selector, at
    the lower right side of the screen in Tux Paint.

    Sometimes, it doesn't make sense for a stamp to be flippable or mirrored;
    for example, stamps of letters or numbers. Sometimes stamps are
    symmetrical, so letting the user flip or mirror them isn't useful.

    To prevent a stamp from being flipped vertically, add the option "noflip"
    to the stamp's data file.

    To prevent a stamp from being mirrored horizontally, add the option "
    nomirror" to the stamp's data file.


     
→ Initial Stamp Size ←

    By default, Tux Paint assumes that your stamp is sized appropriately for
    unscaled display on a 608x472 canvas. This was the original Tux Paint
    canvas size, provided by a 640x480 screen. Tux Paint will then adjust the
    stamp according to the current canvas size and, if enabled, the user's
    stamp size controls.

    If your stamp would be too big or too small, you can specify a scale
    factor. If your stamp would be 2.5 times as wide (or tall) as it should be,
    add one of the following options, which represent the same adjustment, to
    the stamp's data file. (An equals sign, "=", may be included after the word
    "scale".)

      o "scale 40%"
      o "scale 5/2"
      o "scale 2.5"
      o "scale 2:5"

     
→ Windows Users ←

    Use NotePad or WordPad to edit/create these files. Be sure to save them as
    plain-text, and make sure they have a ".dat" extension at the end of the
    filename.


     

                    ### Pre-Mirrored and Flipped Stamps ###

In some cases, you may wish to provide a pre-drawn version of a stamp's
mirror-image, flipped image, or even both. For example, imagine a picture of a
fire truck with the words "Fire Department" written across the side. You
probably do not want that text to appear backwards when the image is flipped!

To create a mirrored version of a stamp that you want Tux Paint to use, rather
than mirroring one on its own, simply create a second ".png" or ".svg" graphics
file with the same name, except with "_mirror" before the filename extension.

For example, for the stamp "stamp.png" you would create another file named
"stamp_mirror.png", which will be used when the stamp is mirrored (rather than
using a backwards version of "stamp.png").

As of Tux Paint 0.9.18, you may similarly provide a pre-flipped image with "
_flip" in the name, and/or an image that is both mirrored and flipped, by
naming it "_mirror_flip".

💡 Note: If the user flips and mirrors an image, and a pre-drawn "_mirror_flip"
doesn't exist, but either "_flip" or "_mirror" does, it will be used, and
mirrored or flipped, respectively.

Fonts

The fonts used by Tux Paint are TrueType Fonts (TTF).

Simply place them in the "fonts" directory. When using the 'Text' and 'Label'
tools, Tux Paint will present the font in the 'Letters' selector at the right,
along with options to enable bold and/or italics, and change the size.

'Starters'

'Starter' images appear in the 'New' dialog, along with solid color background
choices.

When you use a 'starter' image, make modifications, and save it, the original
'starter' image is not overwritten. Additionally, as you edit your new picture,
the contents of the original 'starter' can affect it.

                     ### Coloring-Book Style Starters ###

The most basic kind of 'starter' is similar to a picture in a coloring book.
It's an outline of a shape which you can then color in and add details to. In
Tux Paint, as you draw, type text, or stamp stamps, the outline remains 'above'
what you draw. You can erase the parts of the drawing you made, but you can't
erase the outline.

To create this kind of 'starter' image, simply create an outlined black and
white picture in a paint program, and save it as a raster PNG file, or vector
SVG. If saving as a PNG, you may optionally render the image as
black-and-transparent, rather than black-and-white, but (as of Tux Paint
0.9.21) this is not required.

                         ### Scene-Style Starters ###

Along with the 'coloring-book' style overlay, you can also provide a separate
background image as part of a 'starter' picture. The overlay acts the same: it
can't be drawn over, erased, or affected by 'Magic' tools. However, the
background can be!

When the 'Eraser' tool is used on a picture based on this kind of 'starter'
image, rather than turning the canvas to a solid color, such as white, it
returns that part of the canvas to the original background picture from the
'starter' image.

By creating both an overlay and a background, you can create a 'starter' which
simulates depth. Imagine a background that shows the ocean, and an overlay
that's a picture of a reef. You can then draw (or stamp) fish in the picture.
They'll appear in the ocean, but never 'in front of' the reef.

To create this kind of 'starter' picture, simply create an overlay (with
transparency) and save it as a PNG. Then create another image (without
transparency), and save it with the same filename, but with "-back" (short for
'background') appended to the name. (e.g., "starter-back.png" would be the
background ocean picture that corresponds to the overlay, or foreground.)

For best results, 'starter' images should be at least the same size as Tux
Paint's drawing canvas. (See the "Loading Other Pictures into Tux Paint"
section of Tux Paint's main documentation (README) for details on sizing.) If
they are not, they will be stretched or scaled. This is done without affecting
the shape ("aspect ratio"); however some smudging may be applied to the edges.

Place them in the "starters" directory. When the 'New' dialog is accessed in
Tux Paint, the 'starter' images will appear in the screen that appears, after
the various solid color choices.

💡 Note: 'Starters' are 'attached' to saved pictures, via a small text file that
has the same name as the saved file, but with ".dat" as the extension. This
allows it to continue to affect the drawing even after Tux Paint has been quit,
or another picture is loaded or a new image is created. (In other words, if you
base a drawing on a 'starter' image, it will always be affected by it.)

                            ### Starter Options ###

Aside from an image, starters can also be given other attributes. To do this,
you need to create a 'data file' for the starter. (Note: Tux Paint prior to
version 0.9.29 did not support starter options.)

A starter's data file is simply a plain ASCII text file containing the options
for the starter.

The file has the same name as the image, but a ".dat" extension. (e.g.,
"starter.png"'s data file is the text file "starter.dat", found in the same
directory.)

→ allowscale ←

    When a starter image is a different aspect ratio (width-to-height
    proportions) than Tux Paint's canvas, by default it will be scaled to fit
    entirely within the canvas, without stretching the starter (changing its
    aspect ratio); for example, a square starter on a portrait-shaped canvas
    will be placed in the center of the canvas. By default, Tux Paint will then
    take the strip of pixels at the edges of the starter and stretch them to
    the edges of the canvas, "smearing" it.

    If it's acceptable for the starter image to be cropped in one or both
    directions, the "allowscale" may be used to tell Tux Paint which behavior
    to allow:

      o For starters where it's alright to crop the left and right edges, but
        the top and bottom edges must be retained, use "allowscale=horizontal".
          # If the starter's aspect ratio is wider than that of the canvas, it
            will be scaled to fit the height of the canvas, and the left and
            right will be cropped.
          # If the starter's aspect ratio is taller than that of the canvas, it
            will be scaled to fit the height of the canvas, and no cropping
            will occur, and the left and right edges will be smeared.

      o For starters where it's alright to crop the top and bottom edges, but
        the left and right edges must be retained, use "allowscale=vertical".
          # If the starter's aspect ratio is taller than that of the canvas, it
            will be scaled to fit the width of the canvas, and the top and
            bottom will be cropped.
          # If the starter's aspect ratio is wider than that of the canvas, it
            will be scaled to fit the width of the canvas, and no cropping will
            occur, and the top and bottom edges will be smeared.

      o If it's acceptable to crop either the top and bottom or the left and
        right, use "allowscale=both". Contents from starter will always fill
        the canvas, regardless of how its aspect ratio compares to that of the
        canvas.
      o The default behavior is to not allow cropping. This may be specified
        explicitly with "allowscale=none".

     
→ background ←

    This option allows you to specify how Tux Paint should fill the rest of the
    canvas, when the starter does not fit in one or the other direction. By
    default, as described above, Tux Paint will "smear" the pixels from the
    edges of the starter. (This can be specified explicitly with "background=
    smear".)

    You can instead specify a solid background color (e.g., white for a
    'coloring-book' style starter, with "background=#fff").

    Colors may be listed using three decimal numbers (e.g., "255 68 136") or a
    6- or 3-digit-long hexadecimal 'triplet' (e.g., "#ff4488" or "#F48").

    See the "Color Palette File" section of "Options documentation" for further
    details.


     
→ gravity ←

    This option allows you to specify how Tux Paint should position a starter,
    when it is being cropped in one or the other direction. By default, Tux
    Paint will place the center of the starter within the canvas. (This can be
    specified explicitly with "gravity=center".)

    For example, if the top center of the starter contains the most important
    content, you can specify "gravity=top". Or, if the bottom right is
    important, specify "gravity=bottom-right".

    The available options are:
      o center — prefer the center (the default)
      o top — prefer the top center
      o bottom — prefer the bottom center
      o left — prefer the left center
      o right — prefer the right center
      o top-left — prefer the top left
      o top-right — prefer the top right
      o bottom-left — prefer the bottom left
      o bottom-right — prefer the bottom right

    [ Landscape-shaped image of a horizon with the sun in the middle and a
    building on the right. ]
     

    Focusing on the center of a starter image stretched to fit the width of the
    canvas.


    [ Portrait-shaped image of a horizon with the sun in the middle and the
    left side of building on the right. ]
     

    Focusing on the center of a starter image stretched to fit the height of
    the canvas.


    [ Landscape-shaped image of the sky with the sun at the bottom and the top
    of building on the right. ]
     

    Focusing on the top of a starter image stretched to fit the width of the
    canvas.


    [ Landscape-shaped image of the ground with the sun at the top. ]
     

    Focusing on the bottom of a starter image stretched to fit the width of the
    canvas.


    [ Portrait-shaped image of a horizon with the sun on the left and a
    building in the center. ]
     

    Focusing on the right of a starter image stretched to fit the height of the
    canvas.



     

💡 Note: Templates (described below) may also have options files, and currently
support all of the same options as starters.


'Templates'

'Template' images also appear in the 'New' dialog, along with solid color
background choices and 'Starters'. (Note: Tux Paint prior to version 0.9.22 did
not have the 'Template' feature.)

Unlike pictures drawn in Tux Paint by users and then opened later, opening a
'template' creates a new drawing. When you save, the 'template' image is not
overwritten. Unlike 'starters', there is no immutable 'layer' above the canvas.
You may draw over any part of it.

When the 'Eraser' tool is used on a picture based on this kind of 'template'
image, rather than turning the canvas to a solid color, such as white, it
returns that part of the canvas to the original background picture from the
'template' image.

'Templates' are simply image files (in PNG, JPEG, SVG, or KPX (KidPix) format).
No preparation or conversion should be required.

For best results, 'template' images should be at least the same size as Tux
Paint's drawing canvas. (See the "Loading Other Pictures into Tux Paint"
section of Tux Paint's main documentation (README) for details on sizing.) If
they are not, they will be stretched or scaled. This is done without affecting
the shape ("aspect ratio"); however some smudging may be applied to the edges.

Place them in the "templates" directory. When the 'New' dialog is accessed in
Tux Paint, the 'template' images will appear in the screen that appears, after
the various solid color choices.

💡 Note: 'Templates' are 'attached' to saved pictures, via a small text file
that has the same name as the saved file, but with ".dat" as the extension.
This allows it to continue to affect the drawing even after Tux Paint has been
quit, or another picture is loaded or a new image is created. (In other words,
if you base a drawing on a 'template' image, it will always be affected by it.)


                           ### Template Options ###

Like 'Starters', a configuration file may be specified that defines how Tux
Paint should behave when applying 'template' images to the canvas when they do
not have identical proportions (aspect ratio). See "Starter Options", above.
(Note: Tux Paint prior to version 0.9.29 did not support starter options.)

💡 It's also possible to create basic Templates (with no options) from existing
saved drawings directly within Tux Paint, from the "Open" dialog. They will be
placed in the user's personal templates folder. (Note: Tux Paint prior to
version 0.9.31 did not support Template creation from the Open dialog.)

Translations

Tux Paint supports numerous languages, thanks to use of the "gettext"
localization library. (See the "Languages" section of "Options documentation"
for how to change locales in Tux Paint.)

To translate Tux Paint to a new language, copy the translation template file,
"tuxpaint.pot" (found in Tux Paint's source code, in the folder "src/po/").
Rename the copy as a ".po" file, with an appropriate name for the locale you're
translating to (e.g., "es.po" for Spanish; or "pt_BR.po" for Brazilian
Portuguese, versus "pt.po" or "pt_PT.po" for Portuguese spoken in Portugal.)

Open the newly-created ".po" file — you can edit in a plain text edtior, such
as Emacs, Pico or VI on Linux, or NotePad on Windows. The original English text
used in Tux Paint is listed in lines starting with "msgid". Enter your
translations of each of these pieces of text in the empty "msgstr" lines
directly below the corresponding "msgid" lines. (Note: Do not remove the
quotes.)

Example:

    msgid "Smudge"
    msgstr "Manchar"

    msgid "Click and drag to draw large bricks."
    msgstr "Haz clic y arrastra para dibujar ladrillos grandes."

Various tools exist to manage gettext translation catalogs, so you don't have
to edit them by hand in a text editor. Here are a few:

  * Poedit
  * Gtranslator (GNOME Translator)
  * Virtraal
  * Lokalize

💡 Note: It is best to always work off of the latest Tux Paint text catalog
template ("tuxpaint.pot"), since new text is added, and old text is
occasionally changed. The text catalog for the upcoming, unreleased version of
Tux Paint can be found in Tux Paint's Git repository (see: https://tuxpaint.org
/download/source/git/), and on the Tux Paint website at https://tuxpaint.org/
help/po/.

To edit an existing translation, download the latest ".po" file for that
language, and edit it as described above.

You may send new or edited translation files to Bill Kendrick, lead developer
of Tux Paint, at: bill@newbreedsoftware.com, or post them to the
"tuxpaint-i18n" mailing list (see: https://tuxpaint.org/lists/).

Alternatively, if you have an account with SourceForge.net, you can request to
be added to the "tuxpaint" project and receive write-access to the Git source
code repository so that you may commit your changes directly.

💡 Note: Support for new locales requires making additions to Tux Paint's source
code ("/src/i18n.h" and "/src/i18n.c"), and requires updates to the Makefile,
to ensure the ".po" files are compiled into ".mo" files, and available for use
at runtime.

Alternative Input Methods

Tux Paint's 'Text' and 'Label' tools can provide alternative input methods for
some languages. For example, when Tux Paint is running with a Japanese locale,
the right [Alt] key can be pressed to cycle between Latin, Romanized Hiragana
and Romanized Katakana modes. This allows native characters and words to be
entered into the 'Text' and 'Label' tools by typing one or more keys on a
keyboard with Latin characters (e.g., a US QWERTY keyboard).

To create an input method for a new locale, create a text file with a name
based on the locale (e.g., "ja" for Japanese), with ".im" as the extension
(e.g., "ja.im").

The ".im" file can have multiple character mapping sections for different
character mapping modes. For example, on a Japanese typing system, typing [K]
[A] in Hiragana mode generates a different Unicode character ("か") than typing
[K] [A] in Katakana mode ("カ").

List the character mappings in this file, one per line. Each line should
contain (separated by whitespace):

  * the Unicode value of the character, in hexadecimal (more than one character
    can be listed, separated by a colon (':'), this allowing some sequences to
    map to words)
  * the keycode sequence (the ASCII characters that must be entered to generate
    the Unicode character)
  * a flag (or "-" if none)

Start additional character mapping sections with a line containign the word
"section".

Example:

    # Hiragana
    304B ka -
    304C ga -
    304D ki -
    304E gi -
    304D:3083 kya -
    3063:305F tta -

    # Katakana
    section
    30AB ka -
    30AC ga -
    30AD ki -
    30AE gi -

⚙ Note: Blank lines within the ".im" file will be ignored, as will any text
following a "#" (pound/hash) character — it can be used to denote comments, as
seen in the example above.

💡 Note: Meanings of the flags are locale-specific, and are processed by the
language-specific source code in "src/im.c". For example, "b" is used in Korean
to handle Batchim, which may carry over to the next character.

💡 Note: Support for new input methods requires making additions to Tux Paint's
source code ("/src/im.c"), and requires updates to the Makefile, to ensure the
".im" files are available for use at runtime.

On-screen Keyboard

As of version 0.9.22, Tux Paint's 'Text' and 'Label' tools can present an
on-screen keyboard that allows the pointer (via a mouse, eye-tracking systems,
etc.) to be used to input characters. Files that describe the layout and
available keys are stored in Tux Paint "osk" directory. Each keyboard layout is
defined by a number of files (some of which may be shared by different
layouts).

We'll use the QWERTY keyboard as an example:

                ### Layout overview file ("qwerty.layout") ###

This is a text file that specifies the other files used to describe the layout
and key mappings.

    layout qwerty.h_layout
    keymap us-intl-altgr-dead-keys.keymap
    composemap en_US.UTF-8_Compose
    keysymdefs keysymdef.h
    keyboardlist qwerty.layout default.layout

⚙ Note: Blank lines within the ".layout" file will be ignored, as will any text
following a "#" (pound/hash) character — it can be used to denote comments, as
seen in the example above.

The "keyboardlist" line describes which layouts to switch to, when the user
clicks the left and right buttons on the keyboard. (See below.)

               ### Keyboard layout file ("qwerty.h_layout") ###

This describes how big the keyboard is (as a "width × height" grid), and lists
each key with its numeric keycode (see the "keymap" file, below), the width it
should be drawn at (typically "1.0", to take one space on the keyboard, but in
the example below, notice the "TAB" and "SPACE" keys are much wider), the
character or text to display on the key, depending on which modifier keys have
been pressed (one each for: no modifiers, [Shift], [AltGr], and [Shift] +
[AltGr]), and finally whether or not the key is affected by the [CapsLock] key
(use "1") or [AltGr] (alternate graphics) key (use "2"), or not at all (use
"0").

    WIDTH 15
    HEIGHT 5

    KEY 49 1.0 ` ~ ` ~ 0
    KEY 10 1.0 1 ! ¡ ¹ 0
    KEY 11 1.0 2 @ ² ˝ 0
    KEY 12 1.0 3 # · ³ 0
    KEY 13 1.0 4 $ ¤ £ 0
    KEY 14 1.0 5 % € ¸ 0
    KEY 15 1.0 6 ^ ¼ ^ 0
    ...
    KEY 21 1.0 = + × ÷ 0
    KEY 22 2.0 DELETE DELETE DELETE DELETE 0

    NEWLINE

    KEY 23 1.5 TAB TAB TAB TAB 0
    KEY 24 1.0 q Q ä Ä 1
    KEY 25 1.0 w W å Å 1
    KEY 26 1.0 e E é É 1
    KEY 27 1.0 r R ® ® 1
    ...

    NEWLINE

    # Arrow to left will change to the previous keyboard
    KEY 2 1.0 <- <- <- <- 0

    KEY 133 2.0 Cmp Cmp Cmp Cmp 0

    # The ALT or ALTGR keys are used in 'im' (input methods) to switch the
    input mode
    KEY 64 2.0 Alt Alt Alt Alt 0

    # Space
    KEY 65 7.0 SPACE SPACE SPACE SPACE 0

    KEY 108 2.0 AltGr AltGr AltGr AltGr 0

    # Arrow to right will change to the next keyboard
    KEY 1 1.0 -> -> -> -> 0

Notice here that alphabetic keys ([Q], [W], etc.) will be affected by
[CapsLock], while numeric keys ([1], [2], etc.), [Space], and so on, will not.

Keycodes up to "8" are reserved for internal use. The ones currently used are
described below.

  * 0 — empty button
  * 1 — next layout (per the layout file's "keyboardlist" setting)
  * 2 — previous layout (per the layout file's "keyboardlist" setting)

            ### Keymap file ("us-intl-altgr-dead-keys.keymap") ###

This file defines which numeric keycodes (seen in the keyboard layout files,
such as "qwerty.h_layout" described above) should be mapped to which actual
characters that an application such as Tux Paint expects to receive when keys
(e.g., on a real keyboard) are pressed.

If you're using an operating system such as Linux, which runs X-Window and has
the "xmodmap" command-line tool available, you can run it with the ("print
keymap expressions" option, "-pke", to generate a keymap file.

    keycode 9 = Escape NoSymbol Escape Escape
    keycode 10 = 1 exclam exclamdown onesuperior 1 exclam 1 exclam NoSymbol
    onesuperior
    keycode 11 = 2 at twosuperior dead_doubleacute 2 at 2 at onehalf
    twosuperior
    keycode 12 = 3 numbersign periodcentered threesuperior dead_macron
    periodcentered
    ...
    keycode 52 = z Z ae AE Arabic_hamzaonyeh asciitilde guillemotright NoSymbol
    Greek_zeta Greek_ZETA U037D U03FF
    keycode 53 = x X x X Arabic_hamza Arabic_sukun guillemotleft NoSymbol
    Greek_chi Greek_CHI rightarrow leftarrow
    keycode 54 = c C copyright cent Arabic_hamzaonwaw braceright Greek_psi
    Greek_PSI copyright
    keycode 55 = v V v V Arabic_ra braceleft Greek_omega Greek_OMEGA U03D6
    keycode 56 = b B b B UFEFB UFEF5 Greek_beta Greek_BETA U03D0
    keycode 57 = n N ntilde Ntilde Arabic_alefmaksura Arabic_maddaonalef
    Greek_nu Greek_NU U0374 U0375
    keycode 58 = m M mu mu Arabic_tehmarbuta apostrophe Greek_mu Greek_MU U03FB
    U03FA
    keycode 59 = comma less ccedilla Ccedilla Arabic_waw comma comma less
    guillemotleft
    keycode 60 = period greater dead_abovedot dead_caron Arabic_zain period
    period greater guillemotright periodcentered
    keycode 61 = slash question questiondown dead_hook Arabic_zah
    Arabic_question_mark slash question
    keycode 62 = Shift_R NoSymbol Shift_R Shift_R
    ...

                ### Composemap file ("en_US.UTF-8_Compose") ###

This file describes single characters that can be composed by multiple inputs.
For example, "[Compose]" followed by "[A]" and "[E]" can be used to create the
"æ" character.

The file that comes with Tux Paint is based on the US English UTF-8 (Unicode)
composemap that comes with X.Org's X Window system. The current version from
the Xlib library has a web located page at https://www.x.org/releases/current/
doc/libX11/i18n/compose/en_US.UTF-8.html.

                ### Keysym definitions file ("keysymdef.h") ###

This file (which is a C programming language header file) is also from the X
Window System. It defines the Unicode values of each keycap (e.g., "XK_equal"
corresponds to "U+003D", for the character "=" ("EQUALS SIGN").

💡 Note: This file is not compiled into Tux Paint, but is read and parsed at
runtime.

It is unlikely that any modification will be required of this file.

Magic Tools

Tux Paint's Magic tools are pieces of software, external to the main Tux Paint
application, that are loaded as "plugins" at runtime, and interact with the
program using a defined Application Programming Interface (API). The plugins
that ship with Tux Paint (as well as Tux Paint itself) are written in the C
programming language.

Consult the Magic Tool Plugin API Documentation to learn how to write your own.