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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.

Costumes

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

Do somebody tell me a best nano engineering book for beginners?
s. Reply
what is fullerene does it is used to make bukky balls
Devang Reply
are you nano engineer ?
s.
what is the Synthesis, properties,and applications of carbon nano chemistry
Abhijith Reply
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.
Harper
how to fabricate graphene ink ?
SUYASH Reply
for screen printed electrodes ?
SUYASH
What is lattice structure?
s. Reply
of graphene you mean?
Ebrahim
or in general
Ebrahim
in general
s.
Graphene has a hexagonal structure
tahir
On having this app for quite a bit time, Haven't realised there's a chat room in it.
Cied
what is biological synthesis of nanoparticles
Sanket Reply
what's the easiest and fastest way to the synthesize AgNP?
Damian Reply
China
Cied
types of nano material
abeetha Reply
I start with an easy one. carbon nanotubes woven into a long filament like a string
Porter
many many of nanotubes
Porter
what is the k.e before it land
Yasmin
what is the function of carbon nanotubes?
Cesar
I'm interested in nanotube
Uday
what is nanomaterials​ and their applications of sensors.
Ramkumar Reply
what is nano technology
Sravani Reply
what is system testing?
AMJAD
preparation of nanomaterial
Victor Reply
Yes, Nanotechnology has a very fast field of applications and their is always something new to do with it...
Himanshu Reply
good afternoon madam
AMJAD
what is system testing
AMJAD
what is the application of nanotechnology?
Stotaw
In this morden time nanotechnology used in many field . 1-Electronics-manufacturad IC ,RAM,MRAM,solar panel etc 2-Helth and Medical-Nanomedicine,Drug Dilivery for cancer treatment etc 3- Atomobile -MEMS, Coating on car etc. and may other field for details you can check at Google
Azam
anybody can imagine what will be happen after 100 years from now in nano tech world
Prasenjit
after 100 year this will be not nanotechnology maybe this technology name will be change . maybe aftet 100 year . we work on electron lable practically about its properties and behaviour by the different instruments
Azam
name doesn't matter , whatever it will be change... I'm taking about effect on circumstances of the microscopic world
Prasenjit
how hard could it be to apply nanotechnology against viral infections such HIV or Ebola?
Damian
silver nanoparticles could handle the job?
Damian
not now but maybe in future only AgNP maybe any other nanomaterials
Azam
Hello
Uday
I'm interested in Nanotube
Uday
this technology will not going on for the long time , so I'm thinking about femtotechnology 10^-15
Prasenjit
can nanotechnology change the direction of the face of the world
Prasenjit Reply
At high concentrations (>0.01 M), the relation between absorptivity coefficient and absorbance is no longer linear. This is due to the electrostatic interactions between the quantum dots in close proximity. If the concentration of the solution is high, another effect that is seen is the scattering of light from the large number of quantum dots. This assumption only works at low concentrations of the analyte. Presence of stray light.
Ali 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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