Tartaniser is a program to design and display Scottish tartan (also known as plaid in the USA).
To design a pattern you enter a "threadcount" which gives the colour and number of each group of threads, and optionally a "palette" to specify precise shades of colour for the threads used. Pressing "Enter" will display the resulting design. You can zoom in or out of the pattern. At higher zoom levels you have the option to apply a texture to make the individual threads stand out. You can save and later reload a design. You can save the image of the resulting pattern in standard PNG format, suitable for printing or importing to other programs. The program can handle reflective or repeating patterns (setts), and also the rare cases where the warp and weft (horizontal and vertical threads) use different thread sequences.
Here is the User Guide.
Here is the Download Page.
Here is a screenshot: