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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

Application of nanotechnology in medicine
what is variations in raman spectra for nanomaterials
Jyoti Reply
I only see partial conversation and what's the question here!
Crow Reply
what about nanotechnology for water purification
RAW Reply
please someone correct me if I'm wrong but I think one can use nanoparticles, specially silver nanoparticles for water treatment.
yes that's correct
I think
what is the stm
Brian Reply
is there industrial application of fullrenes. What is the method to prepare fullrene on large scale.?
industrial application...? mmm I think on the medical side as drug carrier, but you should go deeper on your research, I may be wrong
How we are making nano material?
what is a peer
What is meant by 'nano scale'?
What is STMs full form?
scanning tunneling microscope
how nano science is used for hydrophobicity
Do u think that Graphene and Fullrene fiber can be used to make Air Plane body structure the lightest and strongest. Rafiq
what is differents between GO and RGO?
what is simplest way to understand the applications of nano robots used to detect the cancer affected cell of human body.? How this robot is carried to required site of body cell.? what will be the carrier material and how can be detected that correct delivery of drug is done Rafiq
analytical skills graphene is prepared to kill any type viruses .
what is Nano technology ?
Bob Reply
write examples of Nano molecule?
The nanotechnology is as new science, to scale nanometric
nanotechnology is the study, desing, synthesis, manipulation and application of materials and functional systems through control of matter at nanoscale
Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
What fields keep nano created devices from performing or assimulating ? Magnetic fields ? Are do they assimilate ?
Stoney Reply
why we need to study biomolecules, molecular biology in nanotechnology?
Adin Reply
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
what school?
biomolecules are e building blocks of every organics and inorganic materials.
anyone know any internet site where one can find nanotechnology papers?
Damian Reply
sciencedirect big data base
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.
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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