				 Drape
			         =====
			      version 2.0

		        written by Mark Overmars

DRAPE was written to teach people some basic aspects of programming. It
has some resemblance to Logo but DRAPE is completely visually oriented.
Like in Logo, programs in DRAPE create a drawing. A program in DRAPE
consists of a number of commands. There are commands that draw lines and
shapes, commands that move to a particular position, commands that set
properties, like color, line width and size, and control commands, e.g.
to repeat commands, to call procedures, and to test for mouse buttons.

SYSTEM REQUIREMENTS
-------------------

A modern PC, running Windows95 or NT 4.0 or higher is required. The
program requires a screen resolution of 800x600 or higher.


USING AND DISTRIBUTING THE PROGRAM
----------------------------------

DRAPE may be used free of charge, in any way, for any purpose. In may be
distributed by any means, provided that the original files as supplied
by the author remain intact and no charge is made other than for
reasonable distribution costs.

DRAPE may be placed on any archive or BBS system.

DRAPE may not be distributed as a component of any commercial product
without a prior license agreement with the author.



INSTALLING THE PROGRAM
----------------------

To install the program simply unzip the file into any folder you like,
and run it from there. To uninstall, simply remove all files in that
folder. 

Please read the documentation (it is a Word'95 document that can also be
read using Wordpad). You can also read the documentation on the internet
at page

   http://www.cs.ruu.nl/~markov/kids/drape/

Here you can also find information about new releases, extra example
programs, lessons, etc.


CONTACTING THE AUTHOR
---------------------

If you have comments, suggestion, etc. you can send Email to the author:
markov@cs.ruu.nl. Please make clear in the subject line that the mail is
about DRAPE.

CHANGES SINCE VERSION 1.0
=========================

(incompatibilities)

- Environments no longer save and restore color or linewidth.
- Changed the file layout, but the program can still read old
  files. When saved they will be converted to the new format.

(added)

- Two commands were added to set variables (and create your own), and
  to test whether boolean expressions are true. This extends the
  possibilities of Drape considerably.
- You can now use a number of special variables in the expressions,
  like the x and y position, size, angle, etc.
- You can now type in expressions when specifying values. E.g. you
  can set the angle to 360/(23-5). A value "random" is a random number
  between 0 and 1, so you get a random angle by typing a value
  360*random.
- The sound command can now play midi files.
- You can now view and print your program in a textual form.
- Layout of commands is changed to tabbed pages. Three sets:
  easy, normal, and advanced are available.
- An advanced keyboard command with which you can check whether
  a particular key was pressed.
- A command to draw rotated text.

(corrected bugs)

- random positions no longer start at the same place each time.
- repeatedly calling another program caused a nested program
  error, even when the calls where not nested. This is now
  corrected.
- repeated calling procedures causes a recursion depth error,
  even when there was no recursion. This is now corrected.
- Sometimes the program did not correctly skip over a
  block (e.g. after a color check). This is now corrected.
- The Exit command did not work correct from within repeated
  blocks. This is now corrected.

CHANGES SINCE TEST VERSION 0.9
==============================

(possible incompatibilities)

- the advanced move and line commands now work relative to the
  current angle
- images you load and programs you call must now be located in the
  directory where the program itself is stored
- slightly enlarged the stepsize to make it exaxtly 32 on the
  small picture and 64 on the large one. This means that your
  drawings get slightly larger
- Push and Pop Environment have been replace by save and restore
  environments. They do no longer behave like a stack. You can though
  save and restore the environment under a name such that you can
  actualy have a number of different environments.

(new features)

- the size of the cursor is now depending on the current drawing
  size. A move or line commands moves you to the cursor tip
- added sound
- added absolute angle, size and position changes
- added the possibility to place images or text without scaling
- added a command to exit the current procedure
- saving the image is now possible when the program is paused
- there is a command now to save the image
- there now is a single-step mode

(corrected bugs)

- catches deep recursion and other errors
- screen button now keeps pressed after running the program
- keeps track of changes and warns the user when a changed program
  was not saved
- shows the right default filenames when saving a program.
- changed some of the icons
- you can no longer press the pause button when it is already pressed
- paths for images and programs are no longer stored in full, making
  it easier to send such programs to others
- no longer a line is drawn around the image
- picture is cleared when loading a new program and running procedure
  is reset to the first one
- increased the waste basket area 
