Tartan Design

[Swatopluk]

As promised I now start this thread on my new obsession: The Tartan Designer.
Maybe someone can program it based on the stuff I will mumble about.

First here are some of the possible 'elementary cells' for a pixel tartan.

[pieces o nine]

As promised I now start this thread on my new obsession

* pieces trembles at the thought of dozens -- nay, hundreds -- of tartans showing up in picture games *

No, seriously, thanks Swato; this is interesting to me.

[Opsa]

But can you design a tartan appropriate for a squidling?

_{Of course, someone with better eyes than mine will have to sew their widdle kilts.}

[Swatopluk]

Tartan Design (Principles)  Part I

Tartan (or plaid as it is know in America) is a pattern of fabric. To be precise, a regular pattern of differently coloured threads in a woven fabric.
The standard weaving pattern (bind or weave) is twill (2 above 2 below for both warp and weft). Let's define some terms first.

Warp: The vertical threads (x= const)
Weft: The horizontal threads (y= const)
Stripe: A number of adjacent threads of the same colour
Sett: The minimum sequence of stripes that describes the pattern (without the repetition info). For unorthodox tartan warp and weft sett can be different
Repetition pattern: A sett can be simply repeated, e.g. for a 4-sett: (abcd)_n, more common is the reverse-repeat (abcdcb)_n

For a full description of a tartan the follwing info is needed:
Sett (with the individual width of the stripes) for x and y
The repetition mode for x and y
If a twill weaving is intended, the additional info, whether it is forward or backward (the resulting patterns are just mirror images though)

The sett notation is usually: colour, number of threads in stripe
e.g.

b6 k4 y8 g2

= 6 blue threads, 4 black threads, 8 yellow threads, 2 green threads
This can easily be stored as a 2-dimensional array with the number of stripes and total width (sum of stripes) at zero position

For display the info has to be provided, how many threads (or pixels) the trtan shall extend in x and y direction. the relation between threads and pixels depends on the chosen 'pixel weave' as defined by the elementary cell (cf. picture in previous post above).
A thread consits of the colour part (1 or 2 pixels wide) and the border (usually 1 pixel. for broad pattern there can be a another pixel difference).

There are many different 'pixel-weaves' that can be descibed by the elementary cells (the 'rapport' in real world weaving). It is the  smallest n*m pixel pattern that by x and y repetition provides the matrix to be coloured.

There are several methods for how to turn these pixel patterns into a set of easily looped commands and to a degree it depends on the graphic commands at your disposal. The most complex requires only the PLOT command, simple ones make use of LINE, FILL, BOX and FILLBOX.
The method can imitate real weaving with simple unbroken warp lines at the start that are then partilly blocked out by the broken weft.
Another possibility is 'tiling' (overlapping or not) with boxes.
In order to avoid border effects without special exclusion clauses it is possible to first plot the thread borders by use of the elementary cells and then to use FILL for the thread colours. WARNING: This requires a frame round the whole field or there is a risk of 'spill'
The highest flexibility is given by the pixel by pixel approach. For each pixel the computer deducts where it fits in the elementary cell (using the remainder of the modulo operation r_x,y=(x,y mod n) with n the width of the elementary cell) plotting either a pixel of the border (or background) colour or, if a thread is hit (the number of which too can be calculated), the thread colour as stored in an array derived from the sett.
Depiction for the first three methods in the next post.

[Swatopluk]

OK here is a simple (and photobucket-distorted) depiction of three construction methods:


http://i183.photobucket.com/albums/x97/Swatopluk/Streifenmethode1a.jpg

[Swatopluk]

And here are the basic forms a tartan can take with combinations of the orthodox reverse-repeat and the less common simple repeat and equal or different setts for warp and weft:

Please note that the different setts only differ in colour while the pattern is the same (12, 8, 4, 2 threads in black, blue, green, red and maroon, violet, teal, light gray resp.)

Also note that the seond in the upper row has a diagonal symmetry (only) and the last one in the upper row no axis of symmetry at all while all others have at least one horizontal/vertical one (upper left has 4 symmetry axes, two of them diagonal).

[Griffin NoName]

It occurs to me that there may be rules for true tartans that rule some of those out???  Or have you investigated this?

[pieces o nine]

Och, yeah, thaur ur rules.

[Swatopluk]

In theory all of those are 'legal' but designs with different setts in x and y are rare. Most common by far is single sett with reverse repeat in x and y. Simple repeat comes as a far second.

[pieces o nine]

You realize, Swato, that at least one of us is waiting for the *Official* Clan Toadfish Tartan...

[Swatopluk]

Yeah but I have not yet found the perfect mix of stripes and colours. I think about adding a bit of herringbone to the pattern. Since that is still twill it should be covered.

It occurs to me that there may be rules for true tartans that rule some of those out???  Or have you investigated this?

I have to rely mainly on wikipedia for that. Some aspects (esp. weaving theory) are better explained in the German others in the English. None are perfect though. I do not claim to speak with any authority.

[pieces o nine]

I started researching tartans this spring to look for one suitable for a dog kilt. (I know, I know -- my head is bowed in shame, believe me.)

I was amazed that there are seeming millions registered. Have you checked "Scots Tartan Finder" as a reference?

[Griffin NoName]

I feel a Monastery Tartan should reflect tolerant colours and humble shades and should incorprate the subtle hues of Squidlings eyes best.

[Swatopluk]

Working on a squid weave. But that will then not be orthodox twill.
What about this basic colour pattern?
(k24 b12 g8 r2 y1 r2)


That's not yet the final squid 'footprint'. Still experimenting.

[Swatopluk]

So, here is my first true attempt at an unmistakably toadfish monastery tartan design: