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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 in Image 6 . This is particularly true if any special initialization code is required for the sprite, such assetting the current costume to a particular costume, for example.

In addition to the green-flag script, you can also write scripts to handle mouse events, key events, and a special type of event that fires when one spritebroadcasts a message to one or more other sprites. Therefore, Scratch projects are not only sprite-based; they are also event-based. These arerelatively advanced concepts in most programming environments. However, Scratch was designed in such a way as to make it easy to write event-handlerscripts to control the behavior of sprites.

Drag and drop programming

Creating Scratch programs involves very little typing. Instead, scripts are created by constructing stacks of blocks, where each block imparts somespecific behavior to a sprite or to the stage. For example, the project being developed in Image 6 has a stage, (which is always the case) but doesn't yet have any sprites. The stage is represented by the rectangularthumbnail image in the bottom right area of Image 6 . Any sprites that are added to the project would also appear as thumbnail images in that same area.I will refer to this area as the sprite list area.

The physical process for writing a script is as follows:

  1. Select the stage or a sprite in the sprite list area that is to be programmed.
  2. Select the Scripts tab in the center pane.
  3. Select one of the color-coded buttons in the toolbox button area at the top left to expose the blocks contained in a particular toolbox in thetoolbox pane. The toolbox pane is the large pane on the left.
  4. Drag blocks from the toolbox to the scripts (center) pane. (Several blocks have already been dragged to the scripts pane in Image 6 .)
  5. Go back to 3 and continue this process until you have all of the blocks that you need in the scripts pane.
  6. Snap the blocks together in the correct arrangement to create a script that produces the desired behavior.

You will learn the details of such operations in future modules.

Costumes and sounds

Selection of the other two tabs showing at the top of the center pane in Image 6 exposes the controls for importing, editing, and creating costumes and backgrounds, as well as recording and/or importing sound files to be used asmusic and sound effects.

The Scratch programming language

Despite the fact that Scratch has amassed a huge following since its Beta release on March 4, 2007, in my opinion, the language isn't a particularly goodlanguage from a computer science viewpoint. Of the ten or fifteen programming concepts that most computer science professors consider to befundamental to good programming, Scratch supports only a few. Those few include:

Questions & Answers

are nano particles real
Missy Reply
yeah
Joseph
Hello, if I study Physics teacher in bachelor, can I study Nanotechnology in master?
Lale Reply
no can't
Lohitha
where we get a research paper on Nano chemistry....?
Maira Reply
nanopartical of organic/inorganic / physical chemistry , pdf / thesis / review
Ali
what are the products of Nano chemistry?
Maira Reply
There are lots of products of nano chemistry... Like nano coatings.....carbon fiber.. And lots of others..
learn
Even nanotechnology is pretty much all about chemistry... Its the chemistry on quantum or atomic level
learn
Google
da
no nanotechnology is also a part of physics and maths it requires angle formulas and some pressure regarding concepts
Bhagvanji
hey
Giriraj
Preparation and Applications of Nanomaterial for Drug Delivery
Hafiz Reply
revolt
da
Application of nanotechnology in medicine
has a lot of application modern world
Kamaluddeen
yes
narayan
what is variations in raman spectra for nanomaterials
Jyoti Reply
ya I also want to know the raman spectra
Bhagvanji
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.
Damian
yes that's correct
Professor
I think
Professor
Nasa has use it in the 60's, copper as water purification in the moon travel.
Alexandre
nanocopper obvius
Alexandre
what is the stm
Brian Reply
is there industrial application of fullrenes. What is the method to prepare fullrene on large scale.?
Rafiq
industrial application...? mmm I think on the medical side as drug carrier, but you should go deeper on your research, I may be wrong
Damian
How we are making nano material?
LITNING Reply
what is a peer
LITNING Reply
What is meant by 'nano scale'?
LITNING Reply
What is STMs full form?
LITNING
scanning tunneling microscope
Sahil
how nano science is used for hydrophobicity
Santosh
Do u think that Graphene and Fullrene fiber can be used to make Air Plane body structure the lightest and strongest. Rafiq
Rafiq
what is differents between GO and RGO?
Mahi
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
Rafiq
if virus is killing to make ARTIFICIAL DNA OF GRAPHENE FOR KILLED THE VIRUS .THIS IS OUR ASSUMPTION
Anam
analytical skills graphene is prepared to kill any type viruses .
Anam
Any one who tell me about Preparation and application of Nanomaterial for drug Delivery
Hafiz
what is Nano technology ?
Bob Reply
write examples of Nano molecule?
Bob
The nanotechnology is as new science, to scale nanometric
brayan
nanotechnology is the study, desing, synthesis, manipulation and application of materials and functional systems through control of matter at nanoscale
Damian
Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
Renato
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
Privacy Information Security Software Version 1.1a
Good
Berger describes sociologists as concerned with
Mueller Reply
what is hormones?
Wellington
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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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