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
Running the simple example squares.tcl
you receive this output:
This is built up like so:
I wrote a toy FORTH-like interpreter in the past:
That has the same sample program, demonstrating how it could be embedded: