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Scratch development environment

Image 6 shows a reduced screen shot of the Scratch 2.0 development environment. The text in Image 6 is too small to read in most cases. The main purpose of Image 6 is to show you the overall layout of the Scratch developmentenvironment as it appears in your browser.

Image 6. screen shot of the scratch 2.0 development environment.

Missing image.
Image 6. Screen shot of the Scratch 2.0 development environment.

A sprite-oriented programming environment

Scratch is a sprite-oriented programming environment. Every Scratch project consists of none, one, or more sprites and a stage upon which thesprites perform the behavior for which they are designed.

A sprite is an invisible entity to which the programmer can assign numerous behaviors. Each sprite can have one or more costumes. The assignmentof a visible costume to an invisible sprite causes the sprite to also become visible.


The Scratch development environment provides a large gallery of costumes and you can create your own costumes if you don't find any in the gallery that suityour needs. A costume is nothing more than an image. The background in the image is normally transparent. You can import images from a varietyof different file types to create costumes. Probably the most difficult task in creating a costume from an imported image is causing the background tobe transparent (if the image didn't originally have a transparent background) . A built-in paint program is provided to assist in this task. You can alsouse programs such as the free GIMP image editor to deal with the background.

Note that one of the new features in v2.0 is to use both bitmap graphics and vector graphics. I will have more to say about this in a futuremodule.

Walking-boy costumes

The project shown in Image 4 uses five costumes from a family of seven costumes that are available in the gallery. Six of the seven costumes areshown in Image 7 . The project shown in Image 4 uses only the five rightmost costumes shown in Image 7 .

Image 7. costumes for a boy walking.

Missing image.
Image 7. Costumes for a boy walking.

As you can see, the five rightmost costumes describe five stages in a boy walking. The project shown in Image 4 cycles through the five costumes in such a way as to make it appear that the boy is walking. (This process is often called frame animation and dates back to or before the earliest days ofthe Disney productions.)

The stage

The stage is the rectangular area showing the cat in Image 6 . Different images can be assigned to the stage to serve as backgrounds for the performance of thesprites. The gallery contains a large number of background images, and you can also create your own. (One of those backgrounds is shown in Image 6 . ) Usually for a background image, you don't have the transparency issue discussed earlier so backgrounds for the stage can beeasier to create than costumes for sprites.

A moonscape background from the gallery was used for the project shown in Image 4 .

Controlling the behavior of a sprite

You control the behavior of a sprite by writing one or more scripts that belong to the sprite. In reality, each script is an event handler ofsorts. Usually you will have one event handler that executes when the user clicks the green flag at the top right of the stage in Image 6 . (In v2.0, a large green flag button appears when you open a project for viewing in your browser.)

Questions & Answers

anyone know any internet site where one can find nanotechnology papers?
Damian Reply
Introduction about quantum dots in nanotechnology
Praveena Reply
what does nano mean?
Anassong Reply
nano basically means 10^(-9). nanometer is a unit to measure length.
do you think it's worthwhile in the long term to study the effects and possibilities of nanotechnology on viral treatment?
Damian Reply
absolutely yes
how to know photocatalytic properties of tio2 nanoparticles...what to do now
Akash Reply
it is a goid question and i want to know the answer as well
characteristics of micro business
for teaching engĺish at school how nano technology help us
Do somebody tell me a best nano engineering book for beginners?
s. Reply
there is no specific books for beginners but there is book called principle of nanotechnology
what is fullerene does it is used to make bukky balls
Devang Reply
are you nano engineer ?
fullerene is a bucky ball aka Carbon 60 molecule. It was name by the architect Fuller. He design the geodesic dome. it resembles a soccer ball.
what is the actual application of fullerenes nowadays?
That is a great question Damian. best way to answer that question is to Google it. there are hundreds of applications for buck minister fullerenes, from medical to aerospace. you can also find plenty of research papers that will give you great detail on the potential applications of fullerenes.
what is the Synthesis, properties,and applications of carbon nano chemistry
Abhijith Reply
Mostly, they use nano carbon for electronics and for materials to be strengthened.
is Bucky paper clear?
carbon nanotubes has various application in fuel cells membrane, current research on cancer drug,and in electronics MEMS and NEMS etc
so some one know about replacing silicon atom with phosphorous in semiconductors device?
s. Reply
Yeah, it is a pain to say the least. You basically have to heat the substarte up to around 1000 degrees celcius then pass phosphene gas over top of it, which is explosive and toxic by the way, under very low pressure.
Do you know which machine is used to that process?
how to fabricate graphene ink ?
for screen printed electrodes ?
What is lattice structure?
s. Reply
of graphene you mean?
or in general
in general
Graphene has a hexagonal structure
On having this app for quite a bit time, Haven't realised there's a chat room in it.
what is biological synthesis of nanoparticles
Sanket Reply
what's the easiest and fastest way to the synthesize AgNP?
Damian Reply
types of nano material
abeetha Reply
I start with an easy one. carbon nanotubes woven into a long filament like a string
many many of nanotubes
what is the k.e before it land
what is the function of carbon nanotubes?
I'm interested in nanotube
what is nanomaterials​ and their applications of sensors.
Ramkumar Reply
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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Source:  OpenStax, Teaching beginners to code. OpenStax CNX. May 27, 2013 Download for free at http://cnx.org/content/col11498/1.20
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