embedded

embedded example

This directory contains a simple example program which executes a user-supplied TCL script, to generate graphics.

The core of the application creates a graphics area to draw upon, and exports some primitives to the users' script:

• move x y
  • Move the pen to X,Y coordinate
• pen 0|1
  • Move the pen up/down
• turn angle
  • Turn the pen to the given angle
• forwards N
  • Move the pen forward N steps

Together these allow drawing very simple shapes, for example:

    proc square {x y length} {
        move x,y
        pen 1
        forwards $length
        turn 90
        forwards $length
        turn 90
        forwards $length
        turn 90
        forwards $length
    }

    square 50 50 25

Sample Output

Running the simple example squares.tcl you receive this output:

This is built up like so:

Alternative Example

I wrote a toy FORTH-like interpreter in the past:

• https://github.com/skx/foth

That has the same sample program, demonstrating how it could be embedded:

• https://github.com/skx/turtle