MicroWorlds

MicroWorlds is a program that uses the Logo programming language, a dialect of Lisp programming language. It uses a turtle object which can be moved around, given commands, and eventually make shapes or even an animation.

It is part of a large set of dialects and implementations of Logo originating from the invention of Seymour Papert and aimed at triggering the development of abstract ideas by children through experimentation. As a tool for learning, Logo is flexible and provides immediate feedback; it is both accessible to young users and robust enough to create sophisticated projects. In original versions of Logo, Papert created a large 'turtle' that was programmed to move around the room by providing commands via the computer.

MicroWorlds is made by LCSI, and can be used with Windows and Mac.

Syntax

The following is an example of something written in Logo:

to go.crazy
fd 90
lt 90
rt 180
fd 4999              
end

In the example above, the user has gone into a part of the program called the procedure page, which allows for longer series of commands, and therefore more complex programs can be written. In this program, the cursor moves forward 90 units, turns left 90 degrees, right 180 degrees and then moves forward 4999 units.

Another example is:

to say.hi
announce [Hi!]
end

In this example, the user makes a dialog box appear, having the text of whatever is inside the brackets. In this case, the box would have "Hi!" written on it.

Commands can be written in one of two ways: using the procedures page or the command module. The command module allows for instructions to be executed immediately, whereas the procedures page holds instructions that are able to be referenced at any time (using the name written after the word "to" at the beginning of a procedure).

Vocabulary

Logo is based on real words in its 'language' so that they are easy to remember. An example of this is the 'forward' command. 'Forward' can be used in a program such as this:

forward 50

This simple line indicates that the turtle referred to before will move 50 units of computer screen in the direction it is pointed. The unit of measurement for 'forward' is one pixel on the screen. 'Forward' can also be abbreviated as the command 'fd', so therefore can be used like this:

fd 50

Other important navigation commands include:

lt :x 
turns the turtle left :x amount of degrees
rt :x 
turns the turtle right :x amount of degrees
setpos [x y] 
sets the position of the turtle in the coordinates of the screen, x being on the x axis, y on the y axis.
pd 
sets the turtle's "pen" down, so that wherever it moves afterwards, it draws a line on the screen from where it started to where it ended up.
pu 
sets the turtle's "pen" up, so that it does not draw a line anymore.
setsh :x 
changes the picture the turtle appears as to be a picture that is either drawn in Micro Worlds itself or imported into the program. :x refers to the shape's number

This is only a brief example of the hundreds of commands in Micro Worlds.

Versions

MicroWorlds is a basic piece of software that can give a good first start into programming and move on to more robust activities such as programming robotic devices or sensors. MicroWorlds EX Robotics can control a LEGO RCX, a Lego NXT brick and the Handy Cricket. MicroWorlds has the ability to execute multiple tasks independently, also called parallel processing. Several processes can be launched independently which is very helpful when creating multiple character animations and simulations. Extra features in MicroWorlds, for example a text editor, shape centre, melody centre and the ability to import pictures all work with the Logo aspects to create multimedia projects, video games and simulations.

LCSI also provides MicroWorlds JR, an iconic version of Logo that allows younger children who are non-readers begin to learn to program the turtle.

Microworlds has been translated in many languages such as Spanish, Chinese, Portuguese, Italian and Greek.

MicroWorlds is used as the main component of the curriculum used by OpenWorld Learning a non-profit based in Denver, Colorado in the United States, that as to 2007 operated 11 sites in the Denver area.

Microworlds programming can be used to make a variety of apps and games, a benefit utilized by MicroTech

References

This article is issued from Wikipedia - version of the Saturday, March 19, 2016. The text is available under the Creative Commons Attribution/Share Alike but additional terms may apply for the media files.